Grinhill wrote:Sorry for the belated beta-testing report, but I finally got around to running my CA-LRC last week on my Hunter EV Prize race bike.
( Hunter Valley EV Prize thread). I just used a single shunt.
Worked beautifully first go. I plugged in similar numbers to Adrian, and basically ran with that in the race. I really only had five laps of practice, so I didn't change any parameters before the race.
Hey excellent work and congratulations on the build! Anyways I'm sorry too for having left this thread hanging for so long. But trust that it's all for good cause.
I didn't mention yet but I did change the low voltage cutoff to have a 0.1V resolution as Kepler suggested earlier, and made a few other small tweaks at the end of summer which are in the Beta3 V2.24 firmware that is still available as a CA-LRC device for those wanting to experiment. However, the lively discussion, positive testing feedback and extended interest here confirmed that it was time stop this development dead in the tracks and instead opt for a complete redesign of the CA circuit to accommodate all the potential stuff we'd like to do with it rather than keeping hacking onto the existing design. So the last few months have been heavily involved in creating this:
There's now a dedicated thermistor input for measuring (and scaling back power) based on motor temperature, a bidirectional communication port so that firmware can be upgraded with bootloader via any computer with a serial or USB port, a separate dedicated throttle input (independent of the auxiliary voltage input) so you can have on-the-fly current limit adjust and throttle control at the same time, a newer microchip with several times the memory and processing power, a PAS input for measuring pedal cadence in addition to wheel speed, and most fun for me is also a torque input that is compatible with the THUN torque sensing bottom bracket. So in addition to being able to implement a torque based pedal assist feedback mode, we can also calculate and show the human pedal power going into the cranks:
I dunno about others here, but I've always been dying to see just how many watts my legs were adding to the mix when riding an ebike.
Anyways it's probably another 8-12 weeks of coding, testing, and redesigning before being ready for a next round of beta releases based on this new board layout and micro. But I just wanted to give a heads up to all those following this thread that that is where the project is going so you know what's up.
Thanks again for everyone here who has been a part of this. -Justin