Tag Archives: Electronics

hsrdp_pcb_nofill

HSRDP: Joint motor driver PCB (2016, left the project)

The HSRDP as London Hackspace had a fully working board prototype on it. The robotics group has decided to move on from that and change the main microcontoller to the Connected Launchpad vs Arduino Mega, because the chip on Launchpad could do floating point operations and they were needed for the odd nature of calculations in some of the joint modules. Around the same time Eugene has made an H-bridge board for a servomotor using a MOSFET transistor chip 2-in-1. And so he wanted me to use those. My main challenge was to find out how things connect, decide on the Pin connections to the Launchpad and then, the hardest of all, do the track routing so be able to accomodate everything with minimum vias (which turned out to be about 94). The biggest challenge was the fact that the main 2×20 connector had some pins hard assigned, so I could not move them around and had to route around the connector quite a few times. This layout took some time and brain power to minimize things and fit everything in. Three mondays later the PCB layout was complete and we went on to milling it on the Hackspace’s Shapeoko. But that’s an update for later.     Share: Twitter Facebook Google+…

IMG_4123

HSRDP: Steering H-Bridge motor contoller

HSRDP is a Hackspace Robot Development Platform – a robotics group project at London Hackspace. When I first joined London Hackspace me and Pavel Viatkin have noticed it being relatively abandoned in the robotics corner. Later a senior member has informed us that we’re welcome to contribute to the project. Pavel taught me some initial hands-on mechanical and electrical basics that were useful for this project. I’ve tried welding and we’ve mounted the steering motor on the front wheel of HSRDP. Later on I ended up playing around with making an H-bridge motor controller using first simple bipolar junction transistors and later on MOSFET transistors. I had a lot to learn to say the least as I had very little hands on experience with electronics. We had a widely available L298N but it seemed to overheat when controlling the steering motor that we found. The H-bridge I’ve prototyped on a breadboard worked with some tinkering and I would call it a success except that it still overheated. The conclusion was that the steering motor needs a proper PID controller to avoid the constant oscillating around the target point, as that’s what made both motor controllers overheat. Skills improved/learned: arc welding, soldering, H-bridge, transistors, PWM, Arduino, circuit debugging Share: Twitter Facebook Google+…