Assistance needed to prototype from someone who understands electronics!

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Hi Guys
Is there anyone out there who would be prepared to help me with a project. It is a charitable project for Greenpower F24 racing . I have a sponsor who will prototype a board. I need to build the most efficient and robust speedcontroller and use the Teensy to control a fair bit of stuff on the car for optimum efficiency. I need to understand it so that I can explain to the students (I am a STEM ambassador) as you can see it has lots of test points and unnecessary LEDs! It is Teensy based being built for one school, but I have two further schools that when creatred will benefit from the results, possibly more if it is really good!!
I have drawn a prototype on Kikad. H bridge, Bootstrapped, sensors, GPS LORA for telemetry is pending. A lot of it is isolated for robustness. Uses LEDs WS2812 for the dash etc. We are autoshifting a SRAM derailleur with the Teensy. It has Fets for switching horn, fans, brakelights etc. It works as a prototype, but has thrid party sensors all over the place is poorly isolated and has a spaghetti of wires. The issue is not programming for the teenst, but spec of the isolated sensoors, bridge etc.
I just dont know if the circuits are any good or will work! I am also sure they can be improved (most efficient possible for Greenpower....)! Eg I have put in low ESR caps. It is running OK off the T3.5 for 5v tolerances in prototype (pins not fully matched at the moment on the escheema, poor isolation, unreliable due to the wires etc etc) will switch to 4.1 just for fun so have clamped some voltages.
Particular areas of doubt are using op amps with isolated voltage sensors, Thermistors and thermocouples etc.
We are autoshifting the SRAM AXS derailleur which is a great little hack!!
This is the full escheema (have taught myself over last lockdown so apologies for the nature of it!) if there are interested parties to assist I can share as needed if there is interest to assist. This gives an idea of what is involved though.

A typical query is for example: using the isolated voltage sensor ACPL C87 , I think I have to have an op amp to get the output in analog format with a ground. But which op amp? Also measuring the voltage across the motor do I really need two sensors or is there something that will do this isolated in one hit from between the mosfets? My mosfet experience is nil, do both the bridge and the on off drivers really work for the voltages?

Hope I can tempt in an interested few helpers!!

It will be a cool car when it is done .....

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marcopolo303, I just came across this post :)

Hello, my fellow Greenpower mentor. I'm a Greenpower coach here in the US--maybe you have heard of Patriot Racing from Bob Jones High School. As you have probably found, It's a wonderful STEM program and I'm glad to be a part of it. A few links to my team to get an idea of who we are, noting that my students created and produced all of this content.

https://www.youtube.com/watch?v=dFQ6KAHZ3xA
https://bobjonesgpr.wixsite.com/patriotracing


We have built a rather involved telemetry system that measures car performance, displays data to the driver, sends data wireless to the pit for evaluation, sends data to web server that displays data on a smart TV for other teams to watch, has GPS for lap counting and averaging, and a few more goodies. We used to print our own PCBs (single layer), but due to complexity, we now outsource through JLCPCB. We do print our own PCB's for the sensors though.

It was a real *saga* getting telemetry to work due the the electrical noise and the current draw at first start. First version some 6 years ago was on an Arduino NANO--big mistake, but a year we heard of Teensy and moved all devices to a Teensy 3.2. After a few years of chasing and fixing noise issues the unit works perfectly. The team enjoys looking at live data during a race and evaluating driver efficiency after the race (lap distances, energy consumed, etc.).

I can answer a question here or there in design principals, component selection, and a few others, but these units can be complicated--at least for me who is not an EE or programmer--I'm a former mechanical engineer and marketing director. Maybe start with the basics like measuring volts and amps and saving to and SD card. Then add a TFT LCF display, then add ao speed sensors (a real challenge), GPS, then maybe tackle wireless.

Given my battle scars with telemetry, i'm not sure I would start (or even have an integrated motor controller and telemetry), Until you have mastered the telemetry, I would probably use a separate and "store bought" device for motor controller. We had a lot of issues with the 4QD where PWM would never get above around 93% due to electrical noise.

Kris (Coach K).
 
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