sim racing handbrake mod set (force-sensing)

thingiverse

Check out the video of how to assemble it [here](https://www.youtube.com/watch?v=2aMNOjdhkCo).\r\n\r\nThis project is a set of designs to modify a racing handbrake into a handbrake for racing simulators. The KEY FEATURE of this design is using force-sensing rather than a Hall effect sensor or a linear potentiometer to estimate the pulling force. It uses a spring to provide recoil power, getting axis data from a full bridge thin beam force sensor which is connected to the spring.\r\n\r\nHere are several things you need to get it online:\r\n\r\n* Handbrake: I get mine from Taobao. You can use "universal hydraulic handbrake" as keywords to search it on eBay. One example is [this](https://www.ebay.com/itm/BLACK-Universal-Hydraulic-Handbrake-E-Brake-Type-2-Vertical-Horizontal-Drift/122799383241?hash=item1c9769e2c9:g:PzEAAOSwWdZZYyzI&vxp=mtr). This link is just for reference. I don't get it from there.\r\n\r\n* Sensor rack: I use a 12.5mm long 60×15×4mm U-shape aluminum channel to make this part. You may need to file the handbrake a little bit since its width is around 52±0.5mm, while the width of the aluminum slot is 52mm.\r\n\r\n* Spring: I'm using 6×12×55mm, yellow (Light duty) for now. I also tried 60mm long one. For a 6×12×60mm one, the maximum deflection is 30mm, while the maximum force is 137.3N. It works fine. An example with 60mm long can be found [here](https://www.ebay.com/itm/6mmx12mmx60mm-Light-Duty-Stamping-Compression-Mould-Die-Coil-Springs-Yellow-5pcs/232211829242?hash=item3610e751fa:g:kk0AAOSwvApaS4re). You can get other sizes if you want to change the force or maximum deflection. But you will also need to change the 3D design base on the type you get. The maximum force applied to the grip of the lever is about 2Kg (hmm, design failure).\r\n\r\n* Rod: Φ5×60mm stainless steel round rod with M3 thread in one end.\r\n\r\n* Arduino: Get an Arduino Pro Micro. Check out the source code [here](https://github.com/zhyma/force_sensing_handbrake). \r\n\r\n* Force sensor with its' ADC: I get one HX711 weighing sensor module with 20KG scale load cell kit. An example can be found [here](https://www.ebay.com/itm/HX711-Weighing-Sensors-AD-Module-20KG-Scale-Load-Cell-Weight-Weighing-Sensor/151941766596?epid=1153764623&hash=item23606f5dc4:g:Bs0AAOSwPCVX5gqc). You need to modify it a little bit to get a higher report rate (80Hz). Check out the photo of the PCB.\r\n\r\nYou can get the BOM from the attachments.\r\n\r\nEnjoy it!