A hobby project to create a Wemos/Arduino device that can make a cheap dumb trainer a smart one in Zwift Zwift communicates with some expensive smart trainer devices the resistance that you "should" be feeling according to the simulation (ascension grade, current speed, drafting someone etc.) . The smart trainer then increases or decreases resistance you feel at the pedals. My cheap trainer didn't have this capability, but it had a "trainer resistance" lever which pulled a wire. One day I thought, shouldn't it be possible to create a device that pulls/pushes this wire to mimic the behaviour..?
I wasn't the first to think about it, I found Pete Everetts guide later that day and went with my budget from there.
This is an altered version of https://www.instructables.com/Zwift-Interface-for-Dumb-Turbo-Trainer/ by Pete Everett I kept his Bluetooth code but I rewrote other parts of the code to accomodate for my budget version. I think mine ended up costing somewhere between 50-100€ minus the trainer which I had already.
The project worked, and I rode half a winter using it, I recall occasional glitching. My Tacx trainer soon started to show too much wear and instead of polishing the project I went for a Zwift Hub commercial solution.
Parts I used:
- Tacx Satori Smart. Essentially any dumb trainer works that has a "trainer resistance" lever. The lever needs to be the type where it pulls a cable
- Plastic housing with aluminium endplates, 30cm x 15cm x 10cm
- 24V DC PSU
- L298N motor driver board
- Stepper motor from AliExpress https://a.aliexpress.com/_EjRUSAx and mounting bracket from same seller
- LOLIN32 Wifi / Bluetooth development board
- 24VDC to 5VDC adapter for L298N
- Then some microswitches, LEDs, resistors and potentiometers from my local electronics store
Finished end product. Green signals Bluetooth status, yellow is lit when motor moves (or should be moving), red is lit when the motor has ran into a microswitch. Then there's manual switch if I wanted to ride without Zwift, also 2 potentiometers to adjust the scale (meaning the full range of the cable wire could mean anything from -10%..0% gradient to 5%..15% gradient. It's nice to feel a change on a downhill, something like -1%..7% was good
Quite stuffed inside