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Discussion Starter #1
When driving a Tesla, you push the throttle and the car accelerates. When you let off the throttle, the car regeneratively brakes. Brake regen is at max when the throttle pedal is fully up. It's at zero when you press the throttle pedal again...until you let off again...

I'm struggling to understand how this might work with something like a Thunderstruck controller...Is this just a bunch of Tesla computers?

I'm hoping to avoid having to step on the brake pedal to engage a variable amount of regen...It seems like it would be awkward to balance regen, braking, and the bias from front to back...Brakes aren't an area where I want any surprises.
 

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Tesla computers. i've read that they also use the rate of throttle position change as a factor in regen, but that is just showing off.

You could design and build your own regen controller, either in op amp analog circuits, or digitcal in software and microcontrollers.

Some general items to consider:

time-delay filter or hysteresis, to avoid bang-bang regen/accel in case your foot slips off the throttle due to the massive acceleration.

variable regen level using a pot or toggle switch on dash for testing and adjustment.

variable regen based upon vehicle speed or battery pack voltage.

regen using brake pedal switch or brake fluid pressure input.

Does the thunderstruck manual give any info on regen?
 

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Discussion Starter #3
Great info, I appreciate it!

My primary concern with regen is more about minimizing brake dust than it is about increasing range much, so I don't expect to put much effort in until my project is on the road.

It seems like the simplest solution would just be a knob/slider that increases regen over its travel, kind of like the manual lever on a trailer brake controller. Not awesome, but I better than unpredictable braking, I'd think.
 

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..Is this just a bunch of Tesla computers?
It's some code in one computer (or two, if you count the brake controller which should back off friction braking on the driven axle(s) to balance regenerative braking). Every production EV and hybrid does it. There's nothing technically challenging going on here, for someone who is coding the control anyway, but adding functionality to an existing product will always be an issue.
 

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I was loading a Model X, I'm reviving from the dead, onto my car trailer about a week ago -- finally got it rolling under its own power.

Annoying AF. It will not let you drive accelerator & brake pedals simultaneously, and despite having "creep" mode on, it would roll back with pedal let-off.

In other words, they failed to impress me with their nanny-prioritized throttle software.
 

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Discussion Starter #6
This may be straightforward after all...I stumbled on this in the Thunderstruck VCU docs:

If idleregen is configured, the full amount of idleregen torque will be experienced if the motor is turning at greater than 1600rpm and the throttle is completely released.

The throttle position of 0 torque is configurable using the command set deadspot, which is specified in percentage. If the motor is turning at greater than 1600rpm, then a deadspot of 20 means that at 20% throttle the VCU will request 0 torque; larger than 20% throttle will request positive torque (up to maxtorque at full throttle), less than 20% throttle will request negative torque, and 0% throttle will request the full amount of idleregen torque. This feature allows the driver to brake the EV largely by using the throttle only.

In order to smooth the response, the amount of regen requested depends on throttle position and motor rpm when the motor is turning at less than 1600RPM.
Anyone messed with this?
 

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Have you checked out Damien Maguire on YouTube?
He has some great info out there on anything EV.
I'm pretty sure he set the throttle up on one of his projects so the first 30 percent of travel on the throttle was variable regen then the rest was acceleration.
So as you lift off more and more you get more regen and more braking.
As with the motor accelerating you shouldn't get any sudden banging under regen.

Sent from my moto g(8) power lite using Tapatalk
 

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Discussion Starter #8
Now that my car is on the road, I can confirm that the Thunderstruck setup is great. I almost never touch the brakes. It feels very natural, and is configurable to be weaker or stronger, as well as where in the pedal's travel the transition comes on. I'm quite pleased with it.
 

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Did you have to use any of the Leaf canbus system in the Mini or did the Thunderstruck system take care of everything?

Sent from my moto g(8) power lite using Tapatalk
 

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Discussion Starter #10
All Thunderstruck. You can configure where the regen begins in pedal travel as well as how strong it is. It feels very natural after having driven a Tesla for a while.
 
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