Robot platform for STM32F103 (Blue Pill) - Page 1
Forum section: electronics / projects

author: shebu18
author_rank: Frequent Contributor
timestamp: November 21, 2017, 11:22:27 am
content: Hello,I am working on an educational robot platform that is based on the Blue Pill form factor (STM32F103C8T6) chip. The features are:Power:- 1x 18650 LiIon- LiIon charger powered from the USB connector of the BluePill- Switch to select Charging/Programming/Full operationGeneral:- 2 gearbox motors with driver and optical quadrature encoder- I2C port expander with 16 I/O. 4 leds and 4 buttons hard wired- I2C display header (small OLED 64x128)- I2C 6DOF header (MPU6050)- I2C RTCchip- I2C memory chip- I2C temperature measurement chip- rotary encoder with push button- potentiometer- micro SD slot- proto area with access to 8 pins from the port expander- Bluetooth Header- 5x optical sensor for line following application- SPI header- ESP8266-07 soldering connections- small proto areaMy thoughts are if this would have any buyers or general interest because the market is flooded with robot kits.Any thoughts on the setup?Thanks

author: mbless
author_rank: Regular Contributor
timestamp: November 21, 2017, 06:48:17 pm
content: The bluepill already has an RTC crystal, so there's no need for an external RTC chip unless you don't trust the crystal's quality.

author: Cyberdragon
author_rank: Super Contributor
timestamp: November 21, 2017, 07:19:55 pm
content: You need a multi-axis accelerometer, otherwise it won't balance very well on two wheels.EDIT: Yes, you can somewhat balance it with just the encoders, but it'll do the weeble wobbles.

author: shebu18
author_rank: Frequent Contributor
timestamp: November 22, 2017, 08:51:18 am
content: Thank you for the reply.@mblessI do not trust the clock crystal, that is why i decided to put a separate RTC chip on the board@CyberdragonThere is a 3 axis accelerometer and 3 axis gyro extension module available (MPU6050).The robot is not actually designed to be a balancing robot, it can be modified to be one, but it does not have the ideal weight layout. The battery (heaviest part) is in the front and the rotation ax is behind the center. 6DOF unit is actually in the center (not exactly but around there).

author: VEGETA
author_rank: Super Contributor
timestamp: November 23, 2017, 06:35:12 am
content: I suggest you make it for 4WD robot not just 2 wheels. If you want to really take it to next level, you would integrate it with ROS.

author: shebu18
author_rank: Frequent Contributor
timestamp: November 23, 2017, 10:10:59 am
content: What i forgot to mention is that the robot is 10x10x7cm big (WxLxH, 2.5x2.5x2.1in). It uses the blue pill board as the brain, i am not sure if this chip is enough for implementing ROS.Regarding 4WD, i thought about this, but the size is small and turning like a tank with rubber tires needs a lot of power. The solution to this would be to use a tracka ssembly but this omplicates the mechanical part, as right now i can find the parts cheap on ali. The robot is not thought for this. Currently it has 2 motorized wheels and a ball caster as the 3rd support point.The main purpose for the robot is a educational platform for beginners in electronics/robots/arm development. You can buy the robot(different assembly variants) and programmer as a package and install openSTM32. Afterwards clone a git rep and have sample code for every function.