Project eChook Nano: First test success!

A fantastic day at Rockingham saw the weChook racing team manage to run an echook nano for 2 hours on our car Electric 2Galoo. Thanks to all who came to speak to us on the day about the car, as always it’s a pleasure to talk to like minded people who just love to build race cars!

We had great success with out 2 hour test using the echook board both as a motor controller driver board as well as a telemetry data logger. The phone screen was used to inform me (the driver) how much current we were drawing and was perfect for testing our race strategy plans. We also managed to collect 2 hours of good data from our sensors, result!

David @cullimoreracing has kindly offered to run an eChook Nano on Jet2 but we will be looking for more test cars to get these boards on to for the start of the season. Before we do do this we need to tidy up our documentation and work out how we are going to fund the project at this point (the boards are cheap but with components the cost is looking to be ~£30 before you add on the £17 current sensor…we aren’t trying to make any money from this project but we are also not trying to lose too much, we have racecars to build!). We have 9 more boards from this initial batch, watch this space for what we plan to do with them….

Here’s a video describing the main board features

STM32 Programming

Merry Christmas all. Over the Christmas break I have found some time to put together some of the telemtry and control system I have been designing for the driven electric car. I have written this post primarily for my own benefit as it has taken me a couple of hours to get to a stage of programming my board which would have been avoided had it not been for a simple misunderstanding.

The main ‘brain’ of the board is an STM32F103RB, fantastic bits of kit and my first push away from the AVR family I had become so comfortable with at university. At the time of writing I have designed and soldered up a test PCB and have been plating around with getting a program on to the STM.

I am using my STM32VLDiscovery board’s built in STLink-V1 as a SWD programmer. A simple procedure to wire up between the boards (discovery and my pcb) and get comm’s…AS LONG AS YOU DON’T NEGLECT THE ANALOGUE VDD PIN. I had not forseen the importance of connecting this pin initially and had left it disconnected (for the simple reason I couldn’t find the 0603 inductors I had ordered to nicely smooth the analogue supply line going IN to this pin. After a few hours headscratching, checking and rechecking for shorts, I finally found this disconnected pin to be the source of all my problems. Christmas truely has come early.

So watch out for this in the future Ian, and hopefully this note may help someone else in the future.