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I just came back from UYV3, great time, and great bunch of guys.
http://www.99mpg.com/2006events/newevent/

I was able to build up some hands on demos for the event, and they turned out to be a hit.
One of the demos is an Insight block, with only the crank and IMA motor. I run the motor with a Microchip PICdem MC 3 phase driver board. The tiny board can output about 600W, which can spin the thing at about 1000 rpm.
The Synergy Power Split device demo with motors on the three inputs really shows how that cool system works.
The cranker regen demo was the most fun. I put a hand crank on a Prius MG1. The shaft spins freely with little drag with the 3 output wires open. Mild regen is simulated with three nichrome heating elements, which one can light up to glowing red. Max regen is evoked when the 3 phase wires are shorted, It is like mixing concrete with a hand paddle, really tough. MG1 is outputting over 75A into the short.
Next UYV, maybe we make an electric go cart with an insight IMA system?;)

Hi Mike,

Glad to here about the success of your displays at UYV.

There has been some talk about another clutch in the flywheel/motor area, to disconnect the ICE, and allow regen without engine braking. Since you have had all this apart, what is your informed opinion of such. Inquiring minds want to know.

And thanks for your help on the Insight Marathon.

Randall

Hi Randall
While I am not going to say it is impossible (never do), it would be a rough mod to do. The IMA rotor bolts right between the flywheel and the end of the crank. The clutch and throw out assembly fits into the cavity at the end of the transmission.
The motor would have to be remounted to allow for some additional space between it and the transmission, and the whole clutch assembly rebuilt. Not a mod for anyone without a machine shop or spare Insight that they could afford to mess up.

An idea that did come to mind was that the Prius MG2, 40 HP electric motor could replace the whole IMA/ICE for a pure electric Insight. That would mean making a splined drive shaft to fit the MG2 spline, and a way to lubricate the bearings which depend on some splash from inside the synergy drive.

We are also talking about totally hacking the MPI and using just the 3 phase output section with a new controller. We would mount the IMA electric motor on a go cart frame so the guys could experience the full 13HP of electric torque right in the seat of the pants, where it can be fully appreciated. The IGBT driver module is pretty small, only about 7" X 5" X 1.5" thick, and has a nice air cooled heat sink to cool it. We would run it off some Prius subpacks.

Lots of fun taking apart the Insight ICE without needing to put it back together. The demo only weighs about 60 lbs, so one guy can carry it. We drop some slick 50 on the bearings to keep them lubed.
Again Congratulations on the marathon, I bet you guys are happy it is over.
;)

Hi Mike:

___A bit OT. I am not sure if you have been following the HCH-I and II owners wish for a no-Assist switch but in case you have not, this mod would be another excellent outlet for your talents. Put together a small and relatively simple DIY kill-assist switch kit (not a dial in or out full blown MIMA mod) and they will come running.

___Good Luck

___Wayne

Wayne
Thanks for the tip, I have not had much forum reading time lately.
When I get some time, I will look into it.
;)

Hi Mike:

___Thank you for looking into this.

___Good Luck

___Wayne

me me me me me me

I'm catching up too, after being at the very same training weekend.
I wrapped a little story around the pix I shot, viewable at
http://techno-fandom.org/~hobbit/pix/uyv3/ and all explicit
or implied links therein. [Some of you saw this same pointer
via prius_technical_stuff.] It was a fun time, once again,
and it's really vindicating to play around in a shop with people
who do this stuff for a living and still be able to tell them
stuff they didn't know. As a well-informed consumer rather than
an ASE-certified mechanic, that's gotta be worth something.
.
_H*

Great write up Hobbit! And the pics are worth thousands of words. Thanks for sharing!

Amazing. Wish my local dealer was like this.

To even begin to attempt the suggested mod, I would need access to the service manuals, and a HCH to do some test on. The next UYV will not be until Feb, where I am usually too busy to do much playing.
Is anyone in my area one of the HCH owners that want this mod, and is willing to come over with their service manual and do some playing?

Mike

I hope to be moving back there. But alas, currently I'm in Chicago.

Well that will not help us much, there must be a P&G loving HCH owner in New England.
;)

Maybe we can do something during hybridfest ;)

I don't expect to be doing that trek again, just too far.

Wayne
You said "they will come running"
No one even responding to this thread?
You may want to tell "them" in a different thread,that we need a HCH to do the test on before this can happen.
;)

Hi Mike:

___I will post to those 3 HCH owning individuals looking for exactly this mod in the other thread in less then a week. It is not just a P&G mod but a way to disable a design oversight and to extend the longevity of the pack by a great margin.

___Good Luck

___Wayne

Wayne
I don't buy the pack life extension concept. NIMH have a memory. IMHO Not using the pack fully will eventually reduce the pack capacity.
According to Hobbit, The Prius actually has a pack exercise mode where it cycles the pack through the full range occassionally, to avoid the memory issues.
The Fluke NIMH powered scope has a battery life extension mode where it discharges then charges the pack, and the manual recomends using it at least every 3-6 months.
My pack has been heavily used, and I still have no recals, I am presently at 107K, MIMA was installed at 79.5K, thats where the full cycling really began. On the other hand, some of the guys that avoid use of their packs have recal issues.
Neither opinion can be proved or disproved without a more scientific test, so it may be best to present both opinions, and let people make up their own mind.;)

Hi Mike:

___A bit OT. The Prius prismatics appear to be far more robust in their build and SoC management then IMA’s and are not used to blast out Assist on every accel. The numbers of Prius I and II’s sold and the number of problems read about by comparison to the Insight’s are overwhelming. I will leave the Insight’s IMA provided balance question alone … In any case; Prius packs have not gone bad other then a few outliers by comparison. The blasting out of current on every accel is a design issue without question. The guys that ride the packs have far more recals then those that don’t as can be seen by reading the YaHoo - Honda Hybrid groups over the past 4 + years. 19 of 20 bars for 99 % of an Insight’s life as well as temp management in the summer heat should limit your chances of having a recal prone pack. Wrt memory effect, a ¾ SoC cycle twice a year did wonders but that was just me ;)

___Thus the reason for an Assist disable switch would help many HCH drivers for any number of reasons. P&G included but I am sure you have seen what happens to the HCH-I and II’s just like the Insight’s once you get into their Forced charge area. They work just as they should although you will take the hit on the SoC rebuild afterwards. That and the continuous rolling climb some have to deal with where an Assist is all but useless for 90% of ones drive anyway. Yet another great reason to have an Assist disable :D

___Good Luck

___Wayne

As I have stated many times, my experience has been that my pack has not suffered from all the assist cycles I have put on it? If use of assist were a definite cause of battery failure or recalibrations, my battery should have died long ago? Highwater, and Nemystic are both light on the assist, and they both have recalibrations. In light of the amount of recalibrations that the Insight community has seen, I don't think we can say one way or the other. I suspect that the QC on the batteries was not up to the task of building a 120 cell pack that would stay balanced for the life of the car, and the SOC management leaves a lot to be desired as well. The Prius packs deliver assist and regen currents exceeding that of the Insight, but are held within a tighter SOC band except for the occasional full cycles to erase the memory effect.
The right way to manage a multycell series pack is dynamic cell balancing like the tesla and Tzero does with the LI cells.
I expect we will see that type system on future hybrids.

Hi Mike:

___NiMH’s have only so many DD cycles let alone longevity degradation from high C-Rates. Just the nature of the beast. The lower quality HW/SW per design. the lesser their life.

___Good Luck

___Wayne

We never are allowed to deep discharge the pack.The SOC is kept between 20% and 80% to allow many thousands of cycles to avoid the cycle life issues, and the 100A max current falls within the acceptable limits. The IMA Max charge rate of 50A is actually half of what the Prius system allows. There is no direct evidence that I have seen that would indicate that pack recals are related to assist use. If I remember correctly, Armin had his pack replaced, and was experiencing recals right after. I can see how one could theorize that not using the pack would make it last longer, but if Honda knew that (should understand recals better than we do) why did they make the 2006 use assist more agressively.
A report from Joe S to that effect:
As an aside, I just came back from a 10-mile city and uphill trip working very hard to recharge the IMA battery on Wifey's 2006 Insight - that sucker sure seems far more anxious to utilize Assist than my 2002. Succeeded in bringing it up from two bars to full, but it wasn't easy! Sure missed that clutch switch!! JoeS.
;)
Paul Andrews racing Insights, one of which is now MIMA equipped will be the ultamate test of pack life VS assist use.

I think everybody is in agreement that a deep discharge is never a good idea. The time in Jun 2005 I cruised in the Texas Panhandle 90 minutes at 95mph to "show" a black Suburban they could not blow me by is a textbook example of a deep discharge. :o :o :o

The guy I talked with at Lute Riley Honda in Richardson Texas was recommending a driving style between the gearhead and the hypermiler. He would consider me too much on the hypermiling side of the line, but I might agree that a recal every couple of months if it's not a deep discharge might be OK.

Hi Mike:

___The Prius' pack is controlled to a much tighter constraint with the FEH allowed to run in an even tighter SoC band. Evidence. Insight packs are failing all the time. Prius packs are not. The control, C rate capability, and cap save the Toyota Prismatics. Honda has not figured it out yet or does not want to spend the money to design the system properly. You need to drive a Prius rigged with Hobbits equipment or watch the less then accurate SoC guess gauge to see why the Prius pack is so much better protected then the Honda’s. Blasting out assist on each and every accel lessens pack longevity and Honda loves to blast out assist on each and every accel unless controlled with a light throttle. You rely on the pack with Honda’s algorithms and you have a much higher propensity to lose the pack. The Nationwide TSB is testament to this design problem.

___As for Insight replacement packs, Honda is using refurbished (non-CAP matched cel’s) in the rebuilds. I am surprised they work at all :(

___Good Luck

___Wayne

We could go on about this forever, and since we are only offering opinions, no conclusion can be achieved.
Since the words "deep discharge" can mean different things to each of us, I will define it for me as discharge beyond the 0 bar condition on the SOC meter, which the stock system will not allow, therefore my statement that we never see a deep discharge. Obviously others are defining the condition as some where on the active SOC meter range.

With MIMA, we have control of the SOC, and as Highwater, Nemystic, and others have found, one can keep the SOC near the top, or anywhere in between, therefore allowing the driver to use the system as they see fit.
I have stated my opinions, and you have stated yours, now it is up to people to make their own decision as to how they want to use the system.
May all of your batteries be recal free no matter how you use them.;)

It's harder to tell since wa are all early adopters.

The Insight prototype was going to use ultracapacitors.

I predict someone is eventually going to replace the Insight battery pack with ultracapacitors and/or lithium. Heard regulating capacitor voltage is a problem, but they don't wear out and cold weather is not a problem.

Hi Mike:

___We can go on forever but the fact remains, Insight packs are falling like fly’s. I have read of a few HCH-I packs having problems already as well. Prius I and II packs are far and I mean far less prevalent to fail with far more in the field, have larger caps, less range of SoC, and do not blast out assist like Honda’s do.

___As for maintaining a high SoC, Randall, I, and Neymystic know how to do that without manual control. I was just fortunate to never touch the thing other then emergency’s and never could imagine having a recal. It is a lot harder to drive in this fashion whereas MIMA owners should pull back on the assist and regen 95% of the time if not more. The Insight’s packs are to delicate to play with as can be seen in the Hybrid forums around the net.

___Good Luck

___Wayne

Perhaps it's telling that Toyota chose 40 - 80% as their usable
range rather than 20 - 80%, having possibly seen that letting
SoC go down a little farther started getting into cell chemistry
changes despite what Honda [and perhaps everyone] thought a mere
couple of years before that. 40 - 80 basically gives you half
the pack's rated capacity, a mere 600 Wh to play with -- but
if you believe Toyota, within a range that will never come close
to cycling into where cell-lifetime range is affected. That's
what they claim, anyways. Field experience so far mostly bears
that out, although I think there have been a couple of very
isolated bad-cell incidents by now.
.
_H*

Hobbit,
If I remember correctly the Prius pack regularly outputs 100A or more, and can charge at 100A as well. The basic cells are the same capacity, but as you just said, they limit the discharge to 40% SOC.
They also have ocassional full discharges as battery maintenance.
So in fact the Prius does bang out equivlent assist, and charges at even higher currents than the Honda packs. The major difference is the low end discharge cut off point, and the allowed range of SOC.
To this day we are still speculating as to the true reason for Recals. The likely reason being one cell droping out prematurely. The deeper the discharge the more likely the SOC of a weak cell will be reached. May be as simple as that.
Until we can get a multy channel data acquisition scan of the subpack voltages during a recal, it is only speculation.
And my final argument is my 5 year old pack with 109K, and 29K of heavy use and not one recall.
The Insight packs are no more delicate than the Prius, the failures we are seeing are the result of an inferior battery control system, rather than inferior batteries.

Wayne,
Relating to the battery management that we are discussing.
I just got a first report from the last MIMA system I sold.
http://www.99mpg.com/mima/people/andylamm/

Andy drives over the rolling hills of northern IL.
As we can see, Andy is able to keep his SOC at mid scale, and improve his MPG while increasing his average speed. The ability for the driver to become the SOC controller with MIMA can improve the battery SOC management, while allowing the selective use of assist to maintain a reasonable average speed. If Andy's SOC stays in the mid zone, he is effectively reducing the SOC swing to what the typical Prius pack sees, and should see long battery life.;)

Hi Mike:

I saw < 19 bars maybe 5 - 10 times in a year and even cycled the pack twice but never did I have to charge the battery on downhills nor did I see just 70 mpg except during those days when it was ~ 0 degrees F. Maintaining a high SoC and having high steady state speed FE go hand in hand here in the Chicago area. The 2006 Tour Del Sol was a prime example of such even with the 1000 ft. mountains and valleys to overcome again and again ...

Little Red Beauty (http://www.cleanmpg.com/index.php?page=garage&displayunits=MPG(US)&viewcar=48)

___Good Luck

___Wayne

I guess that we would need to qualify what you are calling a "high steady state speed".
You are focused on the max MPG, and Andy and many of us are focused on max MPG going with the flow.
It would be quite interesting if you followed Andy at the same speed that he travels, on the same road, and saw how close you could come to 70MPG.;)

It should be noted that it's a plug-in MIMA

No not true, Andy installed it the hard way, and only has the standard Insight with MIMA.

My bad - getting my hopes up...

Hi Mike:

___You only need to look at my back and forth to work commutes w/ top speeds in the high 70’s and the occasional 80’s or TDS for timed results to see the real world FE of this old hypermiler ;)

___Good Luck

___Wayne

No doubt you have the magic touch.
Good luck to you as well.