MIMA software V2.0

[Mike Dabrowski 2000]

Now that we have nearly 100 MIMA owners,it is time to put together a wish list for improvements to the system.

All of the proposed changes will be backwards compatible with all MIMA harness versions, and some will require new hardware, or new connections to the stock harness.

1. Better display (Video or LCD)and possibily a small keyboard for easier navigation of calibration and setting of variables.
2. MPI and Battery temp display, with alarms.
3. Better joylock
4. Adjustable max assist (done)
5. Auto FAS activation when in neutral
6. Adjustable Auto Background Assist for boosted battery Insights.
7. Auto PIMA compensation of setpoint for gear shift
8. Speed based PIMA operation for those with big batteries, (Cruise IMA---CIMA) this could be an alternate mode of PIMA, where the control signal
is the VSS instead of the MAP.
9.Temporary PIMA disable when in FAS, so the car will not restart.
10. Auto pack whack
11. interface for control and monitoring auxiliary batteries (PHEV)
12. RPM input so MIMA can compensate PIMA setpoints for gear shifts
13. Eliminating the MIMA display by driving the stock assist/regen bargraph directly(thanks Peter). This would free up 10 I/O lines so RPM and other information could be brought into the system.
14. Steering wheel controls

Please add any that you feel would improve the system.

[gpsman1]

This may be a hardware mod, but could you accomplish it in another way?
I don't know.

TPS on demand.
(or auto disable when you press the clutch pedal)
(or auto disable when you lift the throttle all the way)

Like you've said before, it's great for cruising, not great for stop & go when you are going through the gears.

I know for a fact is has at least tripled my lean burn time.

[retepsnikrep]

When you rev engine hard in normal IMA mode assist falls away as revs increase especially near red line. This avoids over reving engine.

When in PIMA mode aggresive assist continues right up to rev limiter and when you then go for a gear change engine will over rev as clutch is depressed.

Suggest Mima modified so assist tails of at high revs like the stock system.

This could be switchable to allow ultra power if reqd when going for max speed.

[Mike Dabrowski 2000]

Interesting:
I guess I don't spend much time at the redline so I have not experienced this.

I do not presently have RPM , clutch, or neutral information coming into MIMA, so that it can deal with that as you suggest, but if we bring that signal into MIMA we can do as you suggest.
I suspect that with speed based PIMA that would not be as much of an issue?

The PIMA/ABC ramp in calibration allows one to tune PIMA's response to a step change in the controlling MAP signal, which jumps rapidly in value when you put in the clutch.
This calibration was intended to tune PIMA's response to the step change, to smooth over the shifts with minimal RPM change. This works like the TPS smoothing hardware, but works in software.
The default setting at center joystick is 50% of the available smoothing. Shift faster, or slow down the response, and the RPM change during a shift can be minimized or eliminated.

Here is the ramp calibration instructions:
C.PIMA ABC ramp rate: Since the MAP signal that is the control signal for both PIMA and ABC can change very rapidly with changes in throttle position and engine load, there is a need to slow down the actual time changes in assist or charge to some more reasonable speed to avoid jerky control. This calibration function allows changing the speed of response of the system to MAP changes. The speed is set with the same auxiliary axis and central switch activation as the other calibration functions. The extreme jog-down (right) position will reduce the ramp speed, the central position is a good default, and the extreme jog-up (left) position will make the speed as slow as possible; say, softening the change between assist and regen. The adjustment has 64 levels. If this adjustment is made while over 19MPH, the throttle can be pressed down and released to experience the different settings effects. The final setting is stored in flash, and will remain in effect until the calibration is again performed. Tap the mode 1 switch to move to the next step.

[retepsnikrep]

Mike

As discussed.

Mima Cruise control with adjustable max assist limit 25/50/75/100%

Compensation for pima to allow for lower gear use.

Compensation for out of lean burn/engine cold pima use so it works the same when warm as when cold.

Peter

[Hybrid-Battery-Repair]

Originally Posted by Mike Dabrowski 2000

Now that we have nearly 100 MIMA owners,it is time to put together a wish list for improvements to the system.

Steering wheel mounted controls. This would necessitate couple pushbutton inputs instead of joystick, possibly combination presses.

[Mike Dabrowski 2000]

Hi guys
I have been talking over the years of coming up with MIMA V2 software.
I hope to get right into that right after the grid charger orders are installed, but want to start gathering information.

With all of the people driving around with MIMA software V 1.58, and older software, and the list of MIMA owners reaching from australia to denmark, UK and Japan, Canada and the US, Over 170 in all, we have a pretty good sized test group.

This is the wish list, please copy and paste or quote this list in all of the responses, so the latest list is right with the comments .

This is the list that I made last year, but in light of all of the great stuff that has been developed since then,IMA power boost, BCM guage, BCM and IMA combined control, BCM software efforts by JoeCVT,Peter, Nasphere, and the gang of teckies that are involved, I see the creative juices flowing, so this may be a great time to redefine what we would like to have on the list, and lets all get on the same page as to how we can make the original MIMA better for us all.

I know that Peter, Highwater, and at least 5 or 6 other guys can burn a new program into their MIMA chips, so that will be the test group. If any others want to get the self programming of their MIMA systems capability, they can get a really nice tool the ICD3 from Microchip. Other less expensive programmers are available.
Development Tools
Development Tools

I will publish test code as a hex file, and the guys with programming capabilities will be able to download and test the new software. Once we get the bugs out, I will offer replacement microcontrollers with the new code burned in, so you can all have some new fun with your MIMA system.


1. Better display (Video or LCD)and possibily a small keyboard for easier navigation of calibration and setting of variables.

2. MPI and Battery temp display, with alarms.(LCD)

3. Better joylock (software tweek)

4. Adjustable max assist (done)

5. Auto FAS activation when in neutral (intergate the regen in idle for MIMA FAS)

6. Adjustable Auto Background Assist for boosted battery Insights.

7. Auto PIMA compensation of setpoint for gear shift (acquire OBDII data from car)

8. Speed based PIMA operation for those with big batteries, (Cruise IMA---CIMA) this could be an alternate mode of PIMA, where the control signal
is the VSS instead of the MAP.

9.Temporary PIMA disable when in FAS, so the car will not restart.( Bug?)

10. Auto pack whack

11. interface for control and monitoring auxiliary batteries (PHEV V-Buck booster system)

12. RPM input so MIMA can compensate PIMA setpoints for gear shifts( OBDII)

13. Retain bargraph but include LCD

14. Steering wheel controls (thanks Peter)

Please elaborate on the items and add any that you feel would improve the system.

[Eli]

Mike, I will post the observations I have made here instead of having them buried in other threads:

Regarding regen in neutral,

I can dial up 4 bars of regen while in neutral with MIMA. It would kinda be cool to be able to do more?

Something else I have noticed, which I assume is a bug - if you rev the car(in neutral) to over 2,500RPM with MIMA, and then pull the joystick back to the regen position, just as the engine's RPM drops to 1,000, you'll get a split second four LEDs of regen and it will stall the engine.

I've actually been using it as a feature. Sometimes in stop and go traffic, the car won't go back into auto-stop. So I use it to kill the car. Putting it back in gear starts it right back up, just like auto stop(though the auto-stop light isn't on, and the dash is lit up like the car stalled).

Hmm. Curious.

When I left work today, my battery fan came on as soon as I started the car, from sitting in the sun all day (I have the IPU case off). I drove around a bit, ran an errand and came home.

I was sitting in my driveway in autostop, listening to the fan running.. when suddenly it went high. OK, I thought.. I'll sit here a little longer and let it bleed some of the heat off.

For some reason, I ended up playing with the MIMA joystick. Every time I would jog it towards assist, two relays would click, and the fan would go low. Can you shed any light on this, Mike?

Thinking about it, you must already know the codes to turn the fan on? But I'm kinda curious why you would have the fan go low when the stock system has it on high? Just an oversight perhaps, or was it on purpose?

I think some more sophisticated fan control may be worth while. It would be cool to be able to warm the pack up when the cabin air is warmer than the battery(and the battery is below room temp).

I also think being able to force regen in neutral would be handy.

[Mike Dabrowski 2000]

Eli,
Can you dial up 4 bars of regen in neutral with a MIMA system I sold you?


I do not amplify the temperature signals as they go into MIMA, as I was simply looking for a temp switch point for fan operation. In retrospect It probably was not a great decision.
The MIMA schematic:
http://99mpg.com/Data/resources/down...rschematic.pdf

As I set up the grid charger temperature amplifier, I determined that best temperature accuracy was achieved with some gain applied to the raw signal.

On the existing MIMA boards, each temperature signal is passed through an Op amp that is unity gain.
Right above the drawing box in the schematic, you will see U2A and U2B, we can increase the gain by simply changing the value of R6 and R8.

In MIMA V2, the temp display scale factor will be set for a bigger signal, and we will just replace R6 and R8 to scale the input signals.

The occasional fan running (Bug)is a result of some noise getting onto the small temp signal and triggering 95 degree fan on comparator. I can likely smooth the signal in software, but I figured like you did that the fan running once and a while was not going to make much difference.
To do a real time pack and MPI display on an LCD, We will need to amplify the Temp signals so it will make the system less noise prone, and provide better temperature accuracy.



1. Better display (Video or LCD)and possibily a small keyboard for easier navigation of calibration and setting of variables.

2. MPI and Battery temp display, with alarms.(LCD)

3. Better joylock (software tweek)

4. Adjustable max assist (done)

5. Auto FAS activation when in neutral (intergate the regen in idle for MIMA FAS)

6. Adjustable Auto Background Assist for boosted battery Insights.

7. Auto PIMA compensation of setpoint for gear shift (acquire OBDII data from car)

8. Speed based PIMA operation for those with big batteries, (Cruise IMA---CIMA) this could be an alternate mode of PIMA, where the control signal
is the VSS instead of the MAP.

9.Temporary PIMA disable when in FAS, so the car will not restart.( Bug?)

10. Auto pack whack

11. interface for control and monitoring auxiliary batteries (PHEV V-Buck booster system)

12. RPM input so MIMA can compensate PIMA setpoints for gear shifts( OBDII)

13. Retain bargraph but include LCD

14. Steering wheel controls (thanks Peter)

15. temperature sensitivity to noise, provide higher resolution and accuracy by amplifying the raw temperature signals for fan control and LCD display

16. Get regen in neutral to work

Please elaborate on the items and add any that you feel would improve the system.

[Eli]

Mike,

Yes, I can. When I first installed MIMA, it was cold(so no auto stop), so I was sitting at lights with the joystick in the regen position to take advantage of what I thought was just wasted gas.

But then I got the Scangauge and noticed that when idling with 4 bars of regen, the engine load goes from ~25 to ~35, and it noticeably ticks your average MPG down faster compared to just regular idling.