MathJax

Friday, September 4, 2015

How To Get Free Land In Canberra and Develop It How You Like

Clubs can make a great free office with lunch and coffee only a few steps away. Select an out of the way table, connect to the WiFi, a mobile phone and your virtual office is complete.  It is comfortable, it's free and I can practice my billiard skills for a break. I'm not unique and I often see others beavering away.  Clubs lack privacy though which made for a fascinating spectacle when a real estate adviser took the next table. Their  team runs seminars, mentoring workshops and personalised advice sessions taking about an hour per client, which I was witnessing. The adviser, based in the Gold Coast was in town to service  Canberra clients. Clients bare their souls, are given life coaching and it is all very pleasant and aspirational.  At some point it usually becomes apparent achieving the client's life goals will need more wealth than they are likely to accumulate from a salary and the coach shows them how the problem can be overcome through leveraged real estate investment.  The first client was living the dream. Single, young with an exciting job that paid an eye wateringly large salary. He was planning his first purchase and  I could see the merits in the consultants arguments. Land just sits there and others give you money to make use of it. You might have to put a building on it before they will but most of what they pay is for the use of land that was just there. How wonderful is that, far better than working for a living. The only difficulty is getting control of it in the first place and the consultant can help with that. The next couple worked seasonally on the ski fields, baby sat their grandchildren overseas in the off season and had $25K outstanding on their credit cards. I'm thinking, stop wasting her time, but they got as much coaching attention as the dream guy. Get permanent work and pay down the credit card, then come back, was the gently delivered take home message. The next guy had two properties already, had paid a deposit on a third and had been refused finance so couldn't settle. It seemed like disaster to me but he was confident his life coach would sort it out and while she she seemed more concerned than the client, she promised she would. I wondered what terms she might get him though as his bargaining position was poor. Whatever she could arrange that cost less than the  already sunk deposit would have to be accepted.

I too was working on real estate and my project was to try and save our local open space. Our government is considering giving some of it away for free to the shareholders of a public company and I could barely believe it was even being considered.

I'd assumed when this eyesore car park took over part of the local oval a few years ago it was built on land that the neighboring company had always owned.
Car park usage on Thursday 13 August, a normal school day. It gets a lot more vehicles through it at pick up and drop off times as a large proportion of the school community is not local.

I had heard they hadn't had to go through any planning permission because it was paid for from building the education revolution (BER) funds and so that these could be spent fast the government had exempted BER projects from normal planning requirements. In my view they had taken advantage of the exemption to build something so cheap and ugly that it would surely not have been accepted through any planning process. When dry it is dusty and pot holed and when raining becomes muddy enough that walking there will leave shoes caked. The picture above shows the level of usage on a normal school day and because it is not nice, the nearby government car park is used preferentially as shown in the picture below, taken at the same time.
This image taken at the same time as the previous image shows that the nearby nearby government car park fills preferentially. Even though it is a little further to walk, it is bitumen, properly maintained and nicer.
All we saw was graders turn up one day and build the eyesore dust bowl on our oval. I was pissed.

Just recently I learned that not only did they beat the planning system to build the dust bowl but it wasn't even their land. They had been given a chunk of our open space for free. Based on nearby property values this huge area of 7760 m2 would be worth about $8 million if used for single dwellings and more for a unit development. It was a common view at the time that it was their land as attested by the first comment on an "Anyone else angry about the Lyneham Oval?" discussion in 2009. Technically it might already have been as they might have been given the land a few years  earlier, it is rather uncertain how they got the land. The explanation from BCE is that "When the two storey Senior College building was developed a few years ago this was only made possible by the ACT Government entering into a 20-year Sub-Lease with Brindabella for the adjacent oval precinct land allowing for the necessary parking the College required to then be able to build to the extremity of the existing College site boundary." That might also explain why the car park is so much bigger than would be required to meet school parking needs. After all when you are getting valuable land for free you might as well grab as much as you can get. How they ever got a large chunk of oval in the first place place, why they got so much and how they did it secretly and without requiring planning permission deserves further explanation in my view.

I'd thought that sort of thing just couldn't happen here, Canberra is famous for restrictive building rules. Years ago in Sarawak I'd stayed for a while in a longhouse that was only accessible by river. My hosts were fabulously wealthy. Rain forest provided most of what they needed for very little effort and collectively they owned a big chunk of it. The forest didn't provide everything though and those other things required cash. Outboards were particularly coveted. Those that had to paddle for long periods were jealous of those that didn't. In common parlance the community was asset rich but cash poor. The community could have sold off a little timber and bought everyone an outboard. They could have sold off some more and built a school and other things they lacked but they didn't seem to seem realise it. I loved my time there participating in ceremonies featuring chicken sacrifices that I didn't understand but I was confident compared to them I was privileged to have a modern education. It hadn't yet reached my longhouse but at many places along the river, the rain forest was being clear felled. The raison dêtre was for the head man to strike an exclusive deal with a logging company to exploit the community land in return for promises of employment and company investment in community facilities. This would be followed by a boom for all, with serious wealth accruing to the head man and the influential. During the boom the promised facilities are inevitably forgotten and eventually the logging company would move on. After the logging company though, the easy bounty from the rain forest was gone and poverty would follow. It seemed inevitable that the process would eventually reach my longhouse and at the time I was confident I was privileged to come from a society where people were well enough educated that they could never be tricked out of their wealth like that. I was shocked that our leaders too had given away a valuable community asset for nil consideration.

There was a time when some of the facilities, for example the basketball courts, owned by Brindabella Christian Education (BCE), trading as Brindabella Christian College, were easily accessible to the rest of the community  but they were fenced off a few years ago.
The basketball court behind this fence was previously available for community access.
This fence creates a clear delineation between what the community can access and what is for the exclusive use of Brindabella Education's School community. It emphasises the them and us of Brindabella Christian School. In the general community accessible area is the BCE rubbish facility, an open drainage channel for BCE storm water runoff and the eyesore car park. Behind the fence are the facilities available to the school community.
Brindabella locates their waste facility outside the fence on land accessible to the general community.

An open drainage canal runs along the outside of the Brindabella Christian Education fence.

Outside the fence Brindabella share the public land along with everyone else which is nice to see. Though perhaps it is surprising that they do when they call it a "bindi laden dust-bowl".


Bindababella Christian College students use the oval as does everyone else.










The dust bowl, or mud bowl when it rains, is however an appropriate description of the little used car park where once the oval extended.

Children play sport beyond the dust/mud bowl car park which is too big for the number of cars using it and was once part of Lyneham Oval.
We have now suffered the dust/mud bowl for six years which was not only going to be sealed but was to have  "some sporting facilities (eg a basketball court)" as well. None of that happened and BCE are now saying:-

In a further development what is now unclear for our College Community is the future of a sealed car-park in any form regardless of the current Sports Pavilion proposal !! as we have been unable to get clarity as to whether Minister Rattenbury will support the permanent tar/concrete-sealing of the current car-park under the existing 20-year lease as a fallback position should there simply be too much opposition to what we are now proposing

So it is quite clear that whatever they promise when getting public land for free it counts for nought once they get it. This matters because the government on the developers behalf is an advocate when Ms Priest from Sport and Recreation said  "This proposed new facility will be a great asset not only for the three schools in the area but also for the local community, and will come at no cost to the territory." 

Their student population is also mostly not from around here so the drop offs and pick ups create a lot of vehicular traffic. That is not to claim, other than the dust bowl, they are a terrible neigbour. All activity inconveniences neighbors to some extent and educating children is important. The school's rapid growth suggests they are providing an education that is appealing to students and their families but whether it is responsible to grow rapidly if you don't have enough land leaves me wondering. Some od their own community is wondering too so "the board of Brindabella Christian College has announced a review of the school's operations amid rising tensions with some parents over a perceived lack of transparency and consultation in key decisions

There is a lot of doubt what those of us outside the school community would ever get from the current proposal. The minister explains "there is certainly an intent to have a written memorandum of understanding"

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which is further explained on the survey site as "an arrangement that will be formalised under a Memorandum of Understanding (MOU)".  An MOU is usually entered into early in a negotiation phase because MOU's create expectations but are unenforceable. In this case there isn't an MOU but an intention to create an MOU, so the Minister is happy give away public land with an intention to create unenforceable expectations despite the past failure to perform. The minister continues "and then the ACT government remains the lease holder with Brindabella Christian College as a sub lessee and so if there are any changes that the government didn't agree with the government of course always has the right to withdraw the lease." Pull the other one, Sport and Recreation couldn't get them to seal the car park, they will never take back the land once there is a building on it.

Land Tenure In The ACT

Nominally all land in the ACT is leased from the state, though land is effectively freehold. No one looks at the lease terms when they buy a home and that makes sense, a state government that tried to take back people's homes would be voted out in an instant. It makes less sense in other situations though and leads to perverse outcomes.

The heart of any community is volunteer, community and sporting groups. These groups provide important services to their members, need space to operate and couldn't exist if they had to rent that space from Westfields or some similarly profit motivated landlord. To support these groups the government frequently leases them land and charges nominal or nil rent. Lease and zoning restrictions restrict land use to the particular activity envisaged. Community groups come and go, sports grow and decline in popularity and in theory the land will be returned to the state when the lease ends. In practise though a lease of any kind over land in the ACT is forever. Sporting/Community groups frequently have the use of land that is worth many millions of dollars if it could be used for residential or commercial purposes. These groups land can have various formal structures and this includes being a public company where the company share holders ultimately own the land. These groups like everyone else in the ACT with leased land regard it as their own and eventually lessees want to generate income from the land they control and become property developers. It is generally accepted that a prime lease is equivalent to freehold but sometimes land is subleased, where the prime lessee is the Sport and Recreation. Sport and Recreation claim when I have asked them at public meetings that land subject to this type of lease is different and will eventually be returned to the state.  Mark from the Sport and Recreation, in a meeting on Friday August 20, to explain the plans for Lyneham oval said there were occasions where sub leased land hand been recovered from lessees but conceded it was rare. Sport and Recreation's views are not even shared by BCE who are using the argument that land previously leased to them for car parking belongs to them. In the BCE brochure distributed via letter box drop, they mount the argument:- "The much quoted 1550 people strong petition against the project alludes to the "future" sub-leasing and development of the Lyneham Oval by private interests, ignoring that the Sports Pavilion would be 80% substantively built on land already leased to Brindabella Christian College by the ACT government until 2029 with lease roll over provisions." Sport and Recreation are asking us to believe something patently false where even the developers are arguing that once you get land under any terms it is yours forever. Why is that?

It is impossible to know when a group initially seeks land what they will eventually do with it, even those seeking the land often don't know as the group changes over time but it is highly likely when ACT leases are in practice equivalent to freehold that eventually the land will be privatised. A current example is "holes 19 to 27 of the Woodhaven Green club"  which are being developed as town houses, another is Canberra City Bowling Club which was sold to a developer planning to "create a 'village-within-a-suburb' and in Lyneham at the moment the whole process is on show in three different developments. These being, Next Gen, a recently completed sports facility, a childcare development on the Hockey Centre site currently wending it's way through an approval process and of course the land acquisition phase on Lyneham oval.

Next Gen

Tennis ACT  got some land years ago and recently partnered with Next Generation Health Clubs Australia Limited, an Australian Private Company. From the Next Gen website you could get the impression that it was a club in the sense of a community group but their advertisement for a General Manager leaves no doubt where it says "Reporting to the COO, you will be responsible for providing leadership and overall direction of all operations along with: Evolving and directing the business strategy to enable the Club to continue with its long term growth, aligned with strong profitability and cash generation". I visited Next Gen to see what the public gets for our money but the public can't even get in. They are kept out by the gate pictured below.
Entry to the Next Gen sports facility. The receptionist told me only members can enter. Even the coffee shop which can be seen beyond the gates is inaccessible. This seems quite extreme for a facility on public land. Some of the facility is tennis courts which are presumably accessible without joining Next Gen but to the casual observer it looks like the whole facility is Next Gen. I could have booked a tour aimed at signing up new members to see more but didn't.
It looks to have been as privatised as effectively as the land our homes are built on. I have been told that the ACT government chipped in money as well as land to this development but don't know if that is correct. Next Gen is a recently completed example of the final stage of the privatisation of public land. Nominally it probably is not yet fully privatised but it seems unimaginable it will ever return to public ownership.

Daycare At The Hockey Centre

A daycare facility to be built at the Hockey Centre is a proposal currently wending it's way through the approval process. Next Gen and the Lyneham oval proposal requires wading through and interpreting marketing material, and most of the interesting stuff is just not accessible. Hockey is up front and provides an informative power point presentation which cuts to the chase. Their goal is to maximise their revenue rather than provide any particular service. At a poorly attended public presentation they said their first idea was a sports medicine facility but that they felt the zoning change would take too long and a child care facility would get cash faster. For the Hockey Centre, the child care facility is a virtual development which removes obfuscation and makes it simple to understand. They get the necessary permissions from the ACT government and flip the land to Kids Club, a commercial daycare provider on a 20 year lease with a 9 year option (slide 11) who builds the facility and pays for the privilege. I'm a little confused on the exact amount they pay and the payment schedule but the slide pack (slide 10) says "$2m capital works @ NHC, $3m childcare" and my notes from the presentation say "$2.7m pitch replacement and $3m sinking fund" so for discussion purposes lets use $5m. The slides also explain that this is the first development with more to follow, including another gym.

Money paid from government through gifts of public land is off the books in that it doesn't have to appear in a budget or be considered for value against alternative uses of government funds. In this case there will be even be documentation to show they paid market value and were actually given bugger all. The $5 million gift emerges by magic from nowhere. Government doesn't have to justify the expenditure and the recipient doesn't have to account for how they spend the money. While the developers are generous in explaining their plans almost no one actually turned up for the presentation or knows anything about it. I wouldn't either if my awareness hadn't been raised by the attack on Lyneham oval as I'd normally rely on our bureaucrats and elected representatives to protect our interests. In Sarawak I'd thought it was lack of education that allowed people to to be sold out but Canberra has the highest education levels in the country and as with the loggers in Sarawak, our leaders are just as keen to sell out their sucker constituents. Everyone wins except those who previously owned the asset. The Hockey Centre proposal explicitly states their "desire to remove ongoing reliance on ACT government funding" (slide 4) but they don't mention that this independence is to be achieved through a huge one off transfer of public funds. Of course, once you get the windfall what you end up doing with it is up to you. The mechanism in this case is described briefly in the slide pack and some further information was provided at the public presentation. The full hockey site of 41,000 m2 is currently held under a concessional lease until 1999 (slide 9) and the land is valued at $520,000 (verbally at presentation). The valuation must be on the basis that the land can only be used for hockey as nearby building blocks of 500 m2 sell for about $500K. This suggests the land is worth about $41 million if it could be used for detached housing and would be a multiple of that if it could be used for higher density housing. To build a day care care centre they must deconcessionalise the land on which it will sit for which they must pay market value. On the face of it the requirement to pay market value would kill the proposal as the Hockey Centre are merely land flipping and if you pay market value one day and sell the next at market value there is no profit. Market value is what Kid's Club is paying the Hockey Centre but as far as I can tell the market value that the Hockey Centre pays the ACT government is on the basis that the land can only be used for hockey, hence the magic $5m when the land is flipped.

Planning Issues

Not only do land beneficiaries get their land for free but the planning process is subverted. At one level there is a Territory Plan for housing here, retail space there, industrial activity somewhere else etc. but when land is acquired for free none of this matters and allowable land use is changed to suit the land beneficiaries. In Next Gen's case their facility is 250m away from a Flames Fitness facility situated on commercial land for which they presumably pay commercial rents. There is also a plan for another gym facility at the Hockey Centrre which is about the same distance from Next Gen. While to me the Hockey Centre looks a great place for a child care centre as it is on a commuter route with good off street parking, it certainly promotes car use and the motivation for siting one there is profit maximisation for the existing lessee rather than better child care or what would be the best use of that public land. Under these circumstances developers can get public land for free with more freedom on how they use it than if they purchased commercial land. 

The Role Of Government

The first public meeting in Lyneham, I've heard of or attended despite living  here for a bout 17 years took place at Brindabella Christian School. During the architects presentation they said, among many provocations, that if BCE didn't get the oval they would build their new building next to the road where it would be ugly and though we would like that a lot less there was nothing anyone could do because schools do not require development approvals. At that stage it was the Department of Sport and Recreations Development Proposal endorsed by BCE and the department was there. The proposal presented didn't pass the sniff test, there were several hundred people that thought so and the mood was vicious.  BCE describes this mood as "people simply resorted to shouting and personal attacks, drowning out any form of civil conversation on the issue." I didn't think it was that bad but I did think that would be the end of it.

Months later there was a second public meeting at Lyneham High School where some variations were presented. This time there only about a hundred people and the mood, while less confrontational was similarly opposed. The Sports Minister, Shane Rattenbury, spoke and said he saw merit in the proposal but was mainly seeking to gauge public opinion. He expressed concern that the audience may not be representational of the wider community. BCE argues "the information session was attended and hijacked by vocal opponents stifling any possible genuine discussion." and that "The generators of the petition have resorted to strategically attending and disrupting any community discussion" but until this public meeting there was no organised opposition, the anger was spontaneous. I was shocked that despite what the minister was saying the proposal was being presented as a fait accompli. The minister was pointing out the positives - there is a need for more community facilities of this type, this land (in his view) was neglected and the ACT's budget position meant that the $1 mill. capital required to irrigate the oval would never become available.  One audience member said the sprinkler system, which hasn't been used for years, had been tested a few months earlier and only two sprinklers failed to operate. It seemed unlikely that BCE would be tipping in $1 mill. into oval irrigation so when I got the opportunity later on I quizzed the minister on this and he said he was merely quoting from figures provided by the department. I pointed out the improbability of BCE spending $1 mill. and he was unconcerned whether the figure he quoted was unrelated to what BCE intended to spend. I was later told by Mark from Sport and Recreation, in a meeting on Friday August 20, that there was an intention to use bore water rather than potable water to reduce watering costs but there was no commitment for any particular spend or irrigation system design from BCE. Perhaps all that BCE will do is connect up a bore and pump to the existing piping, who knows.  Later on the minister doesn't mention the figure but Sport and Recreation still maintains BCE's "recommissioning of the irrigation system" is a principal feature of BCE's proposal.

One audience member sensing the danger said straight up, how do we stop it and got no clear answer. That person later approached the minister suggesting, if there was doubt as to the extent of community opposition the government should survey the community and the minister dismissed the suggestion. This person took up the challenge and initiated a petition which read "The following residents of the Australian Capital Territory draw to the attention of the Assembly the potential loss of Urban Open Space (PRZ1) in Lyneham through sub-leasing and development, in particular by the current proposal to sub-lease and develop Lyneham Neighbourhood Oval.
 Your petitioners, therefore, request the Assembly to prevent further loss of Lyneham’s Urban Open Space by (1) not entering into further sub-leases of Urban Open Space to any business enterprise, (2) not allowing further development on Urban Open Space by any business enterprise, and (3) not rezoning any land currently zoned Urban Open Space for the benefit of any business enterprise."

With help from a few other people he collected 1550 signatures, perhaps the biggest petition ever in the ACT. The text seems pretty straight forward but Shane Rattenbury didn't think so when he said "I do take some issue with the petition that was out there. I've seen it, I probably would have signed it because it says do you object to a private enterprise being able to develop on an oval, and when you put it like that, yer I'd probably sign it too. Ah but I think it is a more nuanced discussion than that and I think it is worth trying to have a more nuanced discussion."
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Of course Shane had seen it, he tabled in parliament, and by inaccurately quoting from it he was subtly suggesting the signatories have been hoodwinked. Shane says "I don't particularly want to put a view we are just starting a public consultation process today to try and gauge the community view."
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So after two public meetings and a huge petition we are just starting the public consultation process. Really Shane? How will you gauge public opinion?

According to Shane "To try and help the government get a clear sense of where the community is at on this proposal we are trying to be very open in putting this out to a community survey and so all residents of Lyneham down to Macarthur Avenue and even though some of that's O'Connor it is really part of the community ahh and all the parents of the three schools are being sent a survey to ask them their opinion and this will, I guess, give us a really objective and measurable ahh. Because one of the questions I was asked at a recent public meeting was how does the government decide what is a meausure of community sentiment. That is a really good question and one I've given a bit of thought to and a public meeting where 100 people turn up, is that a full measure of the community sentiment or is it just the really motivated people that turn up to a public meeting but the rest of the community has a different view so we are trying to get that broad community sense."

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The minister issued a similarly worded press release press release where again he says "The survey is open to residents within the Lyneham area, and parents/carers of children who attend any of three schools." 

This survey turns out to be online using a commercial tool which is totally inadequate for surveying opinions on anything controversial. Registration is anonymous, multiple registrations are possible and even with the same registration it appears to accept multiple votes. There is no way to restrict voting in the way the minister claims.  Perhaps his claim relies on the Do you live in: check box on the voting form. Survey integrity was questioned at the Sport and Recreation meeting on Friday August 20 at Lyneham Primary School. Jenny Priest and Mark said they would use voter IP addresses to ensure integrity. Is it to be one vote per IP, does that mean more than one person can't vote from one house, does it mean votes when people are outside their home are invalid were questions asked? They couldn't answer. IP address is a notoriously poor method of geolocating someone and a contract issued on Mechanical Turk could get as many votes as you wanted for your favourite case from uniques IP addresses.

As a tool for seeking feedback on controversial issues it is a joke. It requires a lot of effort to find and participate in while allowing voting from anyone, multiple voting, voting from anywhere and has propaganda for the yes case only, on the voting site. For example it says "Given that the proposal is wholly funded by BCC, it will only proceed in its entirety" but at community meetings we were told the building would be built regardless. At the first we were told the likely alternative location is at the front of the school and at the second next to the Motor Inn where some existing buildings were old and due for demolition.

Compare this to the electoral commission which maintains electoral rolls, makes surpeople are entitled to vote, there is only one vote per person and doesn't run propaganda material from one side of the debate. Minister Rattenbury said "I do take some issue with the petition that was out there." and then followed up with a consultation process which is farcical. The petitioners all list there name and address and this offers huge opportunities for checking and analysis. If you doubt the validity you could even ask some if they really did sign. An interested government could also ask some petitioners why they signed. Analysis by address would be really useful. I collected about 100 of the signatures going door to door and my experience was that a lot of people weren't home. Of those that were, more than half didn't know anything about the proposal. Most of those signed and of the people that were aware well over 90% signed. Objections to signing were varied and often vague so are not easily summarised. I came across two people who said they had children at Brindabella School and one was keen on the development and the other opposed on the grounds that their children would be there only a few years but the oval would be gone forever.

While Minister Rattenbury in his public utterances claim he is mainly seeking community feedback BCE have advised he is far more committed than that where they say "Due to concerns of the Minister Brindabella agreed to withdraw the previous DA to engage in further public consultation on an offer by Minister Rattenbury to then fund our resubmission following further consultation"  Actually BCE come across as annoyed that what they saw as a firm commitment from government has become less so where they argue "Originally our Sports Pavilion proposal had the then support of Minister Andrew Barr as Minister for Sport & Recreation and Minister Joy Burch as Minister for Education. In the more recent portfolio moves the proposal has now fallen to Minister Shane Rattenbury as the Minister for Sport & Recreation. 

This begs the question as to what our politicians are up to. First they think giving away public land for free is acceptable, then they do it secretly (in the case of the car park give away) and when people object they remain resolute. They are also doing it all over Canberra, they have just been beaten in a developer give away in Telopea Park where "Telopea Park School's Parents and Community Association president Paul Haesler said that in this latest battle he had always been confident the Government could be pushed back because its decision was "so manifestly and obviously flawed and unfair." In this development  Canberra Services Club were planning to generate cash from turning leased land into housing and the politicians fought hard on the developers behalf.

In the longhouse it was also plain there a lot of people were opposed to bringing the logging company into their rain forest. My host family were opposed to selling out but they were the opposite of influential, they didn't even own an outboard. Rafts of logs drifted past the longhouse all day long and the runoff from the newly cleared jungle further along the river muddied up the water and ruined the fishing. Fish were previously accessible next to the longhouse and fishing was still good in small tributaries but those without an outboard were suffering reduced social standing because they had to spend so much of their time paddling to get there. Others had more time to relax and the really wealthy bought tinned fish from Kuching and didn't have to fish at all. There is something to be learned from this, it is far better to join the winners and prosper than fight them and suffer with the dispossessed.

The Business Opportunity

The underlying opportunity is that, with a plausible story, prime land can be acquired in the centre of Canberra for free. In most of Australia property developers can make money by purchasing land and then waiting or lobbying for rezoning so that it can later be resold at a higher price. Developing under these conditions requires substantial capital and a risk that you won't get a favourable rezoning. If that happens you are stuck with holding costs and will probably lose money.  The ACT is much better. As the land can be acquired for free, resale is all profit. This also means no interest expense, resulting in negligible holding costs and therefore negligible risk of loss. In the acquisition phase you will have to accept restrictions that limit profitability but any promises you make will eventually be forgotten. The politicians can be persuaded to support your acquisition and in the face of community opposition, government departments will help promote your development. Then after waiting a while and some more lobbying the land use can be changed and you get to control the distribution of the profits. Spend them on a community project you care about or pocket them, the choice is yours. Our government promotes these as activities public/private partnerships. Extreme capitalism doesn't get any better than that and the ACT Greens can even be persuaded to spruik for you. Who'd have thought?

Opportunity Specifics

There are several ways I can immediately think of to exploit the underlying opportunity. At the community meeting with Sport and Recreation on Friday August 20 one idea suggested was to seek the support of the neighbours in return for storage rights, to build a garage on public land near the proponents house. This would require establishing an organisation to undertake the endeavour and seems too blatant to pass the plausible story test.  It also lacks ambition, a bit of isolated land could only generate modest profit. Better to think bigger. Buying shares in Brindabella Christian Education Limited (BCE) is a great opportunity. BCE is a non profit public company which I'm told is a requirement for running a school and this presents both opportunities and difficulties. The opportunity is that shares ought to be cheap to acquire. Shares would normally be valued as a multiple of dividends so shares that can not pay a dividend by this valuation method are worthless. Of course the shares have no value to the acquirer either if there is no way to extract the company's capital but I feel confident this can be overcome. Non profits can't pay dividends but are notorious for paying out profits in other forms. One technique that would work is to acquire sufficient shares to get a directorship then collect directors fees, another would be to engage a for profit management company to manage the asset. You also have to generate the cash to extract, the land is worth millions but only if you can sell it. Soaking the school community to generate revenue through fees just doesn't seem reasonable. I pondered over this problem for a while and then found inspiration on the BCE website where they mention the next door "newly proposed development of the Lyneham Motor Inn which is to incorporate some 300+ apartments in twin 8-storey towers. A separate fight for the College to have as and when this proposal develops." There is a great way to win this fight, liquidate enough of the BCE land to generate a lot of cash, make it look like a new school/community asset has been created and therefore provide a good argument for the required zoning change over the BCE land. Plot ratios will limit the number of units that can be built on the Motor Inn site so expanding the land area allows more units without necessarily building on the particular piece of additional land. A joint facility using BCE land would do it. A pool and spa facility would look good in the school prospectus and would help sell the unit development or perhaps an outdoor entertainment/sport area. Continued access to this land for school purposes can be guaranteed with a memorandum of understanding. Memorandum's of understanding are ideal. The seller gets full value from the land sale because the purchaser promises are unenforceable and the ACT government regards memorandum's of understanding as sufficient for giving it's blessing to development proposals and even land grants.

Buying shares in BCE is much better than the garage proposal as it is less blatant and can generate more profit, but I'm aware of an even better opportunity. I know of another community group operating on public land that is smaller than the BCE or the Hockey Centre plots but is even better located. It would be ideal for unit development which seems to generate the most profit. The community group organisers are all voluntary, driven by altruism and like most community groups that provide valuable services at less than cost, they suffer from lack of funds and free riders. A few hundred high rise units on their land to fund new facilities for the community group and fund paid staff would really get the group humming. There would still be lots left over for the benefit of insiders. Surely the offer from the property consultants on the next table could be improved on. Free land in the centre of Canberra has got to be better than negative geared apartments on the Gold Coast.

To capitalise on this opportunity you also need to join the party while it is in full swing, I doubt there is much to be made from clear felling rain forest in Sarawak anymore. Eventually the government will run out of land to give away and while a lot of the good stuff is already gone there is still some good land available. The site I have in mind is prime land for high rise residential development, close to shops and amenities and with water views. Just like Garden Island, Sydney as depicted in Utopia, it is a developers dream. As with the longhouse, once it becomes inevitable that the community asset will be lost, the smart people jump on the bandwagon and fight for their share.

Perhaps I can partner with the guys on the next table. They have the marketing muscle, then we need some partners who know how to win over the politicians. Someone from the Hockey Club, Canberra Services Club or BCE would be good.  I'm sure these organisations are driven by altruism so I don't know if they can be persuaded to join an endeavour as mercenary as I have in mind but they have the necessary skills. There is even one person on the boards of both BCE and the Canberra Services Club. We can form a team and party hard!

Sunday, February 16, 2014

Making It Easier For Heavy People To Pedal Up Hills

In bicycle racing, big guys win the sprints on the flat because they have more power and the slight increase in rolling resistance from the extra weight doesn't use much power. The climbers however, are always tiny because human power output doesn't increase proportionally with weight even when the extra weight is all muscle. For many non racers that extra weight is mainly fat which is always a hindrance. They may be able stay with their colleagues on the flat but on a hill they'll be dropped. The usual (and best) strategy is to lose the fat but another solution is to use some assist to carry the extra load up the hill. People sometimes spend thousands of dollars to carry just one or two kilos less bicycle weight up hills and a little assist would be a cheaper alternative.

The goal is to make hills as easy to climb for heavy people as light people or alternatively to make hills less steep even to the point of requiring the same effort as riding on the flat. Say you weigh 90 kg but your riding colleagues way 70 kg and have expensive bikes that are 3 kg lighter. You want enough extra power to carry 23 kg up the hill so you can keep up with them. If you add enough power to carry your weight plus the bike weight, perhaps 12 kg, equating to 102 kg in the example case, then riding up a hill will feel the same as riding on the flat.

The extra power to achieve this is supplied by a motor and to know how much power to request from the motor requires knowing the weight of the rider, the weight of the bike, the speed of the bike and the grade of the hill. Three of these parameters are easily determined but the grade is more difficult.

Barometers can measure height change without calibration using the hypsometric equation. Constant temperature can be assumed to remove the need for a temperature sensor. This increases error but eliminates error due to inaccurate temperature sensing. Air temperature sensing is difficult because the sun can heat the sensor housing. A change in sunlight levels from cloud or sun direction as the bike changes direction can cause the housing to change temperature while external air temperature remains the same.

Measuring grade requires the change in pressure to measure the height change plus the distance travelled between pressure measurements to get the grade. This is how the IpBike app estimates grade. Normally distance is measured using wheel revolutions but I think it will use GPS distance in the absence of wheel sensors. So a barometer would do the job except that you need a reasonable height change which takes a while on a grade. This would mean no help from the motor at the start of the hill and extra motor power after the hill had already passed.

Alternatively an accelerometer can measure the grade with a fast response. This overcomes the problems of the barometer but introduces more. An accelerometer will respond to changes in speed as well as grade. Braking will look like descending and reduce assist and accelerating will increase assist which is  good because the motor will also compensate for the heavier rider during acceleration. Longitudinal vibration will be sensed and may require a little low pass filtering. A single axis accelerometer has to be aligned with the direction of motion and be perpendicular to gravity but this is not practical to do. The readings from a three axis accelerometer can be rotated to match this alignment:-

\(\begin{equation} Acceleration_T = a(A_x- K_a)+b(A_y- K_b)+c(A_z- K_z) \end{equation}\) where \(\begin{equation} \text{$Acceleration_T$}\\ \end{equation}\) is acceleration in the direction of travel, \(\begin{equation} \text{$K_a, K_b$ and $K_z$}\\ \end{equation}\)are accelerations due to gravity in the particular axis direction, \(\begin{equation} \text{$A_x, A_y$ and $A_z$}\\ \end{equation}\) are measured accelerations and \(\begin{equation} \text{$a, b$ and $c$}\\ \end{equation}\) are the components of a unit vector in the direction of travel in the coordinate system of the accelerometer.
\(\begin{equation} \text{$K_a, K_b$ and $K_z$}\\ \end{equation}\) are calculated as the average of a three axis accelerometer over a long enough period while riding. They can be calculated as a moving average over a period of minutes while travelling faster than 10 km/h but will gradually rotate when climbing a hill to match the grade.

Lifting the front of the bike while stationary so that it rotates through about 30-45 degrees and sampling the accelerometers will give a second vector. Taking the cross product of this and the gravity vector defines an axis about which the bicycle rotates when it climbs a hill. This measurement and calculation should only need to be done once as a slight change in sensor rotation about the bike's vertical axis will produce only a small error in the final result. Taking the cross product of the rotation axis with the gravitational vector gives a third vector normal to the other two and therefore in the direction of travel. The scaler components of this vector after normalising provides the values \(\begin{equation} \text{$a, b$ and $c$.}\\ \end{equation}\) Using Newtons second law, the force required to counteract this acceleration along the grade produced by gravity is:-
\(\begin{equation} F= m \times Acceleration_T \end{equation}\) where \(\begin{equation} \text{m}\\ \end{equation}\) is the mass we wish the motor to carry up the hill and the power required to do it is calculated as \(\begin{equation} Power = F \times Speed \end{equation}\) Motor power controlled with this sensor would give immediate help at the start of a grade but in a long hill the power would fade over time.

The barometer is slow to respond but more accurate over time and the accelerometer that self calibrates is responsive but inaccurate over time. Fusing the two sensor outputs gives the best result and this can be done with a simple complementary filter or kalman filter . The assumption that the measurements are corrupted by stationary white noise produces a stationary kalman filter that is identical in form to the complementary filter according to a comparison of complementary and kalman filtering for combining measurements of vertical acceleration and barometric vertical velocity to obtain an estimate of vertical velocity.

In inertial measurement units gyroscopes are often used for sensing rotation but for this case do not add useful grade information.

Tuesday, February 11, 2014

What Killed Noelene and Yvana Bischoff?

Surely not food poisoning.

Following reports that an Australian woman Noelene Bischoff and her 14 year old daughter Yvana died in Bali after falling ill only hours after checking in to room 7 at the Padang Bai Resort, I was curious.

Food poisoning was suspected but I've frequently been ill after eating in Bali and couldn't imagine, not just one, but two people dying  from food poisoning within seven hours of becoming unwell? So I visited the Padang Bai Resort.

After first seeming to know nothing of the incident, as she'd been off that day, the lady on reception advised she was unaware which room they had become sick in. When asked specifically for room 7 she advised it was unavailable but we could have room 6. I'd already seen 7 was unoccupied but she said it was booked.



Padang Bai is a small harbour in Bali from which boats leave to neighbouring Lombok and which features diving, snorkeling and a modest coral reef.



Traders along the waterfront were confident that nothing bad had occurred in Padang Bai, suggesting the  Bischoffs had become ill elsewhere and merely arrived in Padang Bai before the effects became severe. They were also sure the fish served in Padang Bai was healthy as it was caught locally. In press reports the resort manager Mr Bareato had also said the resort buys fresh fish from local fishermen each day. The enthusiasm of locals to maintain the reputation of their community I've found common in Bali, as well as a tendency to blame Javanese when there is trouble. This attitude minimises robbery and violence, as mostly people are looking out for visitors which may in part, stem from recollections of economic devastation in the wake of the bombings. A terrible time for locals, but a period of heavily discounted abundance for visitors that weren't discouraged.

Twelve hours before their deaths, Sunshine Coast mum and daughter Noelene and Yvana Bischoff laughed and joked with waitstaff over a seafood lunch in Ubud and this meal was thought unlikely to have been related to their demise.

Just metres from room 7 is the Buddha Restaurant which the lady on reception had advised was a separate business to the hotel. It was here they ate dinner around 7 pm. So we tried it for lunch.



We asked the waiter about the Bischoffs but he knew nothing about the incident. The press reported the Bischoff's had ordered mahi mahi fish, chicken curry and vegetarian pizza. Just six and a half hours after the meal, Noelene was dead. It was the mahi mahi fish which doctors say is the main suspect.

A day later another Australian, Heath Barclay, fell ill five hours after eating a ham pizza. A Facebook friend mentioned the Bischoffs, "I then check the net and to my horror I had eaten at the same place and had fallen violently ill," Mr Barclay said. "With the police [crime scene] tape in full view of my room at the hotel it was a living hell – I thought I could be next." The 34-year-old plasterer rushed himself to a Denpasar hospital where he was put on an intravenous drip for nine hours. "I was blood tested and told I had severe dehydration and a bacterial infection from food," he said. "I don't really know what would have happened if I didn't go to hospital. If it was the same thing, I can't imagine how terrible it would have been for a 14-year-old girl." However, I can imagine his colleagues on the building site having fun comparing his reaction to that of a 14-year-old girl. Of course it wasn't "the same thing", just the usual unpleasantness of food poisoning combined with the uncertainty of where it originated when he, as I usually have done, ate in more than one place over the previous couple of days. However, it raised suspicions of the pizza and the cleanliness of the kitchen. I glanced in the kitchen and it looked spotless and better equipped than most Bali restaurants. I asked the chef about the Bischoffs but she said she knew nothing and had been rostered off that night. Most staff in Bali work punishing 10 - 12 hour shifts, six days a week so you can be pretty confident of meeting someone that works in a business by turning up at any random time. Padang Bai Resort seems far more generous with leave provisions than most or perhaps we were unlucky. Like Heath Barclay, so far we'd learned nothing more than what had been in the papers.

At lunch Jarrod, in the foreground, couldn't be persuaded from his perennial favourite, sweet and sour pork. Jenny, on the right ordered the vegetarian pizza, but it was only available after 6 pm. Not desiring chicken curry, she settled on leek and potato soup. I requested the mahi mahi (pictured below).



Jenny reported the soup tasted as good as it looked.



The mahi mahi was served with chips and a side salad. It too was lovely. Following a pleasant lunch we went snorkelling and sightseeing. There were no ill effects.



The sudden and mysterious death of two family members was undoubtedly distressing. ‘‘We want the truth,’’ the family spokesperson said. ‘‘We want to know if it was an accident, or if it wasn't an accident. Were they poisoned, or was it something else? ... "We’re worried that there will be a cover-up if the autopsy is done in Bali." Indonesian authorities respected the Bischoff family's request and allowed the bodies to be returned home for autopsy.

A colleague suggested it was probably medication administered in response to initial symptoms that was the culprit but we'd left Bali, none the wiser. Eventually the preliminary autopsy finding was that they died from a combination of food poisoning and existing medical conditions after they ate fish". It was reported that "Malcolm Bischoff, Noelene's brother, said it appeared they both suffered from scombroid food poisoning that, coupled with their asthma and, in Noelene's case, migraine medication had formed a fatal cocktail." My colleague hadn't got it quite right but it was a prescient observation.

Malcolm Bischoff stated "I'm sure we wouldn't have got that answer if the autopsies had been held over there [in Bali]" I'm not so sure, but the Indonesian authorities were wise because Malcolm would likely have been sceptical of the same findings from them. Having accepted the results, Malcolm said "scombroid food poisoning can result from eating spoiled fish, meaning the restaurant's preparation could have made no difference". This defence of the restaurant might be helpful as there was only one other patron having lunch when we were there. He hadn't heard of the Bischoffs and, better informed, some of my party would have preferred to eat elsewhere.

According to the Courier Mail, "scombroid food poisoning occurs when fish like tuna, mackerel, sardines and mahi mahi, is left in temperatures over 5 degrees. After the fish has died, naturally-occurring bacteria can then convert the amino acid histidine into the toxic histamine which can cause severe, allergy-like symptoms." Histamine is not destroyed by normal cooking temperatures, so even properly cooked fish can be affected.

While the autopsy is not yet finalised it seems that the Bischoffs were unlucky. The other people that ate the same fish included the resort manager Giovanni Bareato. They probably didn't have the complicating factors and scombroid concentration varies in different parts of the flesh.  None reported ill effect.

Despite the confidence of the traders that no one from Padang Bai was involved, it does implicate the fisherman who supplied the fish. Had the fish been refrigerated there would not have been scombroid and I'm surprised I've not seen this angle pursued. I don't know the practises in Padang Bai but I've seen fisherman elsewhere in Indonesia selling their daily catch straight from the boat without ice or refrigeration. Convincing fishermen of a need to change this practice is probably a difficult task but, as with Heath Barclay and the Bali bombings, human reaction to tragedy is rarely nuanced, tending to indifference or panic. I'm sure the traders of Padang Bai want to avoid the latter and another scombroid death might provoke it, even though motorbikes is the more common source of tragedy.

Thursday, February 6, 2014

Vernelli Road, NSW - A Secret Public Road

Well it would be a secret if not for Google maps suggesting it as a route from Queanbeyan to Araluen. 

Not far from Canberra in NSW, Australia is an intersection of Gumms road and Vernelli road. Gumms road is a through road but from Vernelli road it is disguised as a gated farm entrance. It is a region where it seems easy to imagine that intergenerational incest could remain hidden among the "smaller farms, used increasingly as hobby farms or boltholes for those on the fringes of society".


View Larger Map

Coming from Gumms road, turning right on Vernelli road takes you to Harold's Cross road but turning left is more interesting, the route of a songline. A songline is a path across the land originating from the dreamtime known only to insiders, usually Indigenous Australians of past generations. To outsiders they are invisible and in my youth I'd found the concept difficult to grasp. What I couldn't see, didn't seem real but nowadays I find it fascinating that what people see is hugely influenced by their frame of reference. Traditional songlines are recorded in song and markings, noticeable only by the group, but modern day songlines, also  known only by insiders are recorded in apps like Strava and Google maps. They exist only within a context, can be overlapping and may have no physical indicators.


A GPS track along the almost secret 7 km section of Vernelli road. There are two wadable water crossings, numerous gates and some steep sections.

Turning left, the dirt road with many gates services only three houses. Vernelli road becomes impassable to normal vehicles as it approaches the  third house, 1.1 km from Gumms road. It is a lovely house, off the grid and secluded by trees just above Bourkes creek. It's as hidden as it is possible for a house to be and was only visible looking backward from the creek. Beyond the creek there is only some wheel ruts and after a while they fade as well. I was here on a bicycle, fortunately mountain style, because Google maps had suggested it as a route from Queanbeyan to Araluen.

However, without the GPS tracking live on a map as I rode I wouldn't have believed it was a road or been able to follow it. On the ground there is sometimes no indication which way to travel, though in places there is cuttings and grade smoothing, indicating it has been a substantial road in the past and in others there is a few metres of  trees separating the road from surrounding paddocks. These are the physical evidence confirming this songline, recorded in cyberspace.


A view down Vernelli road which passes between the trees in the centre of the image. It is taken from the location indicated in the GPS track image above. Grass growing in the wheel tracks indicates the absence of regular traffic.

There are two Strava sections labelled Vernelli (Road/Rd) Climb. The most popular with 20 riders starts in Gumms road, turns right into Vernelli Road and provides a route to Cooma road that is more substantial but longer than the route I followed which Strava records just 3 riders traversing. Without any physical evidence, an observer without Strava  would have no idea this songline exists, yet the creator (not me) and a few insiders know I'm the king of this mountain, probably the only one I'll ever rule.  These insiders can form a whole community that is invisible to non members. Another cyclist is recorded  coming this way, travelling from Wollongong to Melbourne in another instantiation of modern songlines; cycling routes. Perhaps Vernelli road also follows an Aboriginal songline as; being a short route meandering along ridge lines to the Shoalhaven river, it fits many of the criteria.

If you're passing through then Vernelli road, down to Cooma road, is an interesting path which you would never find without becoming an insider but for those on their own, don't get injured as it might be weeks before another insider comes by.

Thursday, January 3, 2013

A Stealthy Motor To Cycle Fast

My suggestion that low power assist is all you want received support and scepticism in a discussion at Endless Sphere. Having formed the view you don't need much help to cycle fast I'm wondering how it can best be done and wish to select a motor and model some scenarios.

What's Out There?

The Gruber Assist, shown in Figure 1, provides a high cost, low power solution that is visually stealthy enough for Fabian Cancellara to be accused of using it during Paris Roubaix and the Tour of Flanders but too noisy for it to be true. Detailed performance information is unavailable but reviews are generally enthusiastic. Negatives reported are 50% efficiency and simple on/off control.

Figure 1: The Gruber Assist is a stealthy 100W output motor that resides in the seat tube.
Bosch mid drive motors have integrated control and display, use pedal torque sensors and offer several operation modes. They appear close to ideal but I'd prefer a mobile phone as the display device, at 4 kg they are heavier than some alternatives, they need a frame designed to fit, and the control algorithms are not published and can't be altered or integrated into cycling tracking applications. Some other mid drive e-bikes are available, like the low cost Aseako/Zoco Rossa.

Friction drive, shown in Figure 2, provides an alternative using small, high speed RC motors but the transmission losses driving the tyre are probably high.

Figure 2: A lightweight friction drive.

Other alternatives are hub drives which are either direct drive or the lighter less powerful geared motors.

Albert van Dalen has done an investigation of bike motors that focuses on efficiency and compares them on weight vs rated power.

Silence Is Beautiful

Modern bicycle motors are brushless DC with six step trapezoidal control explained in this video. Controllers are cheap, from about US$18, but produce motor torque ripple that is often audible. For little additional expense, controllers could use better algorithms to eliminate noise. Figure 3 shows an example of noise reduction in a direct drive hub motor using sinusoidal control.


Figure 3: An example of noise reduction achieved in a direct drive hub motor with sinusoidal control.
There seems to be a gap in the market as only trapezoidal controllers are commercially available.

Torque ripple is avoided by rotating the magnetic flux vector so that it is always perpendicular the magnetic flux vector of the spinning magnets which can be achieved with field oriented control. In contrast to applications like washing machines, torque loads on e-bike motors vary slowly and typical e-bike motors produce sinusoidal back EMFs1. Under these circumstances the simpler sinusoidal control generates the same output as field oriented control.

Field oriented control is often suggested as a means of increasing motor efficiency. In a simulation Johan Astrom2 found only a marginal efficiency improvement with an optimal control scheme over trapezoidal control for a 375 W motor because a non perpendicular magnetic vector mostly acts to store and release energy in different parts of the cycle.

Geared motors can also produce gear noise. The lightweight Tongxin/Keyde hub motor uses rollers rather than gears which is reported as effective for motor silencing but may increase gearbox friction losses.

Regulation

Previously, unregistered electric bikes in Australia were required to "be able to prove that the motor output is not more than 200 watts" but there were no restrictions on how that power could be used. Recently the European standard EN 15194:2009 was introduced as an alternative which allows motors rated up to 250 watts continuous while requiring riders to pedal at speeds above 6 km/h (clause 4.2.4.3.1) to receive assistance and restricting assistance to speeds below 25 km/h. With the usual controllers, a 200 W maximum means much lower power over most of the operating range, so most Australian electric bikes probably exceeded the previous requirement. For those bikes that didn't, the change from "not more than" to "continuous" means motors are potentially a lot more powerful than a 50 W increase would imply. The continuous motor rating power is only loosely related to instantaneous power as shown in figure 4.
Figure 4: The rated power is at the intersection of the rated speed and rated torque lines. The position of the sloping line is determined by the rated voltage. The rated values are nominated rather than physical properties of the motor.
The continuous motor rating is a value assigned by the manufacturer at which the motor is guaranteed not to exceed temperature specifications as defined in IEC 60034-1 clause 8.10 - Limits of temperature and of temperature rise.  As an example, Bosch mid drive motors, rated at 250 W, have input power measured in figure 5, above 600 W for considerable periods while climbing a 5.5% grade pedalling at speeds around 23 km/h prompting reviewers to conclude the "Bosch mid drive feels as zippy and fast as 750-watt hub motor bikes."

Figure 5: Bosch mid drive input power while climbing a 5.5% grade pedalling at speeds around 23 km/h. Output power is probably about 75% of input power.  
Fast cyclists exceed speeds of 25 km/h, so incapable riders seeking to keep up will need assist at speeds above 25 km/h. EN 15194:2009 clause 4.2.6.2.2 c) specifies that the maximum speed test should be conducted at 1.25 times the rated speed, therefore some assist can actually be provided up to 31 km/h and still comply. This is above the speeds the average rider can maintain on flat ground but far short of the 41.6 km/h Chris Horner maintained over 172 km in the sample ride. Bosch overcome this limitation by also selling a "Drive Unit 45" version which lifts the rated cut off speed to 45 km/h.

Motor Selection

The Cute Q-85SX/GBK-85F, detailed in this drawing was suggested by Albert van Dalen. It is nominally 1.6 kg but was tested as 1.84 kg including electrical cable. He doesn't consider a lighter, nominally 1.2 kg motor in the Cute drawing, which may not be purchasable, and he chose the Cute over the Tongxin/Keyde which is nominally 200 gm lighter at 1.4 kg as the Cute was more easily acquired3. Accepting his motor recommendation, Albert's motor testing data can be used to model e-bike scenarios.

Motor Model

Albert conducted a carefully documented motor investigation and dynamometer test from which he constructed a motor  model. The dynamometer data, in figure 6, shows evidence of saturation beyond torques of 20 Nm, corresponding to a motor current of 12.9 amps, so a model is only valid for torques <20 Nm. Saturation could be avoided with more iron, but space is limited so that would necessitate less copper, increasing electrical resistance and reducing motor efficiency at torques <20 Nm. To avoid rapidly increasing inefficiency and overheating, this motor should be operated at currents less than 12.9 amps, though higher currents are sometimes used. This matches the Ku63 controller which limits current to 12 to 12.85 amps.

Figure 6: Dynamometer test data

Albert measured motor winding resistance as  ≈ 0.307 Ω (stated as  but intended as Ω) but elsewhere he calculated R = 0.77 Ω which is a substantial difference.  He accounts for the difference as gearbox friction and uses the measured value in his model, however the relationship:- Vo = (I * R) + (ω * Ke) which is expressed in Albert's notation as U = (I * R) + (ω * k) is independent of gearbox friction losses. Rearranging to k = (U - I * R)/ω, the motor constant (k) can then be plotted against rotational speed (ω) of the wheel using the dynamometer test data as shown in Figure 7.

Figure 7: Motor constant k versus ω with R = 0.307 Ω. Slope should be zero.

Adjusting to R = 0.75 so that the slope of a linear estimate of k = 0 gives the result in Figure 8.

Figure 8: Motor constant k versus ω with R = 0.754 Ω. Mean value of k = 1.55.  Note: The y axis scale is different to figure 7.  
The inconsistency of the estimated resistance with the measured resistance is a mystery which would be good to resolve. The estimated resistance is used for the motor model.

Torque is measured after the gearbox and is reduced by friction losses as shown in figure 9.

Figure 9: Different types of friction losses sum to the total friction loss. Friction at velocities near zero are ignored as  very low speed behaviour is not modelled.  
The losses in torque due to viscous and coulomb friction in the gearbox and motor can be modelled as:-
T = (Ts - Cv * ωs - Cc* Ts) * GR
where:-
T = wheel torque (Nm)
Ts = torque before the gearbox (Nm)
ωs = motor speed before gear box (rad/sec)
Cv = viscous friction coefficient
Cc = coulomb friction coefficient
GR = gearbox gear ratio

Combining with the motor equation:-
Ts = ks * i
where ks = motor constant before gear box (Nm/A)
and:-
k = GR * ks
where k = motor constant at the wheel (Nm/A)
and rearranging gives:-
k = (T + Cv  * ω) / (i *  (1 - Cc))


Figure 10: Motor constant k versus motor speed ω with R = 0.754 Ω. Mean value of k = 1.55.

Values for Cv and Cc can be found numerically to best match k to the previously determined value while minimising the slope of a linear estimate of k as shown in figure 10.
Resulting in:-
Cv = 0.033
Cc = 0 which means Cc can be ignored in the motor model.

The patterns evident in figure 10 suggest the model is not fully representative of the motors behaviour but the resultant errors are acceptable and being determined from large numbers of independent measurements should be considerably less than the estimated 5% error for individual measurements.

The parameters R = 0.754, k = 1.55 and Cv = 0.033 can be used to construct the motor model which can then be combined with the previous bike model and used for simulations of electric bike scenarios in a future post.

References

  1. Renesas Application Note: 180 Degree Sinusoidal Motor Control  Based on this document; pg 3; " As many brushless motors have sinusoidal BEMF ..., it is possible to match these motors with a sinusoidal driving voltage."
  2. Johan Astrom;  Investigation of Issues Related to Electrical Efficiency Improvements of Pump and Fan Drives in Buildings; PhD Thesis; Department of Energy and Environment, Chalmers University Of Technology, G¨oteborg, Sweden 2011; Figure 6.23 pg 97;  The graph shows marginal improvement, about 3% maximum in part of the efficiency/load curve with an optimal control scheme over standard BLDC motor control for a 375W motor. 
  3. Personal correspondence.