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Old 12-19-2009, 02:38 PM   #67 (permalink)
RobertSmalls
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Join Date: Aug 2008
Location: Buffalo, NY, USA
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Prius C - '12 Toyota Prius C
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I've wanted manual control of the IMA system since I bought the car. There are four functions I need. Three down, one to go:

*disable regen and assist when I don't want them (the clutch switch mod does this)
*idle stop at any vehicle speed (engine kill switch + clutch switch)
*regenerative braking on demand (pressing the brake pedal just enough to turn on the brakelight works fine)
*assist on demand (I need MIMA_L)

MIMA_L is a DIY, manual IMA control system. It's a lie-box that sits between the ECU and IMA ECU. You'd use a hand throttle or other analog controller to dial in as much assist as you want. That would be very helpful when you're trying to hold lean burn up a hill or during slight acceleration. I have no doubt it would improve my fuel economy noticeably. Eventually, I'd like to combine Mima_L with grid charging, for an even greater reduction in gasoline consumption.

Here's the schematic. It's complicated. Two op amps, three IC's, two SPDT relays. It will have to be breadboarded, and I haven't breadboarded before.

I'd like to simplify the circuit slightly, and I think Jim wants to do the same. I'm comfortable eliminating the 12p header, which also means you don't have to mess with the wires that were connected to pins 9-12. Logic GND can share with power GND. The "on/off" indicator LEDs are a nice touch, but I won't include them unless they're built in to toggle switch SW2. Okay, so that would be a little simpler, but still pretty complex. Does this schematic have any other expendable components?

I will add Mima_L to my Insight, but first I have bigger fish to fry. More on that fish once it's fried.
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