Usefull? No, but fun and challenging to build.
I just finished a prototype for controlling the rear wheels.
Link to more information:
https://www.thebackshed.com/forum/ViewTopic.php?FID=4&TID=12074
It’s something I’ve been working on for a few days now, it’s basically a steel frame made of 50mm square 5mm thick bars. The wheels are BLDC hub motors taken from 2 cargo scooters. They are 48V, but because I don’t need the speed, driven on a 20Ah 24V LTO battery, and even then I limited the speed with software. The bldc controllers are build myself with 6 fets per 3phase bridge. I added hall sensors to the wheels, so I could make a controller based on the mc33035 with mc33039 run in closed loop. An arduino nano is used to decode the receiver signals and puts out the 0-5V needed for throttle. 2 small relais are used to let the MC33035 know to change direction. I use 3 hall sensors to meaure the phase current, with an opamp circuit it is fed as one signal in the mc33035, to do current limiting.
Phase currents were limited to 40A for safety but had to set it to 80A to have enough power to go over obstacles. I will need to change the mosfets to something like HY4008 or IRFP2907, IRFP4110,… to stay in a “safe” zone.
Next is adapt the mowing deck, the pulleys are replaced by 2 individual 48V bldc motors. I need to build an other controller for that and wait for parts that are ordered.
The deck will be interchangeble with my lawn mower that is also converted to electric.
I hope to upload more video’s of my home made projects.
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