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Old 12-28-2015, 05:33 PM   #2490 (permalink)
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Originally Posted by thingstodo View Post
Is this a programmable setting or are you using 'solder' to adjust the regen?

Do you want to use a single input to the controller, which varies from small regen to full acceleration. And the pedal rest position must be a high enough signal to allow for another circuit to 'pull the signal down' for more aggressive regen. Did I get that right?

What happens if you have a Toyota throttle problem - unintended signal for large acceleration - as well as brake signal? Do they cancel each other out?

I like the idea for a very simple interface for throttle and brake on one wire.

I'm having trouble visualizing how a hall effect throttle can give decent performance for you unless you have access to the firmware of the controller to adjust regen slopes or lookup tables.
I can't answer for Astro, but I think these questions bring up some very valuable points.

I think it would be best to have the user input completely software adjustable. This would allow easy adjustment for all throttle and brake behavior. I saw a review of the Lightening motorcycle where they spoke of the "accessable" power of the bike. The torque didn't come on immediately with a tiny twist of the throttle. This would make the bike very difficult to ride. I've also seen non-linear throttle curve parameters on controllers. Again, this will make the power and torque more accessable.

Regarding the Toyota "unintended throttle" problem and Hall-effect sensors. I think hall-effect sensors are more reliable than standard potentiometers. All standard potentiomters have a finite life span due to the wiper contacting the resistor. I just replaced the potentiometers on my stove because they produced unreliable output at about 25%. Hall-effect sensors do not have this issue. Also, hall-effect sensors generally operate between 0.5V and 4.5V, out of a 5V range. This gives the opportunity for software to test for open or short circuits if the voltage is out of range.

In addition to that, the Toyota throttle pedal has two hall-effect sensors. The outputs are arranged physically so that they look like a hystresis curve. This allows the code to continually check between the two to make sure there is no issue with the hall-effect output. I like redundant systems with easy error checking.

A similar setup with redundant sensors could be implemented on the brake pedal. At the very least, it should have an output range like the hall-effect sensor to detect correct operation vs a short or short circuit.

- E*clipse
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