The B-G431B-ESC1 Discovery Kit is a programmable ESC 6S Lipo (40A peak) available for only 18USD. See : https://www.st.com/en/evaluation-tools/b-g431b-esc1.html. This compact ESC (20x40mm) has USB, CAN and PWM user interfaces. The STM32G431 may be reprogrammed with a custom firmware, in order to drives a home made brushless servo (MAD 5008 240Kv). A position-velocity-torque regulation, with velocity and acceleration profil, has been tested. With a 1:10 planetary gear box (3d printed), the torque may exceeds 50kg.cm (5Nm) at 24V @ 5A, and the velocity is quite good (about 0.1s/60°).
The latest firmware update improves the bandwidth of the position and torque PID controller.
This test was performed with my robot powered by Lipo 4S battery. The robot is under development. It is a 8-dof quadruped using MAD 5008 240kV motors, B-G431B-ESC board, 3D printed planetary gearbox (ratio: 1:4.5) and a M5Stack Fire.
This compact ESC was designed by ST for drones, with a strong forced convection.
At zero-altitude, zero-speed, without propellers, thermal dissipation remains an issue.
Problem solved ! (Joke) ^_^
I have absolutely no experience in implementing FOC algorithm. This is my very first project, about brushless motor controller. I will do my best to release and share something basic but usable soon.
The Discovery kit embeds the hardware circuit for encoder sensor. A supply voltage line is provided with 5 V and GND lines in J8 solder pads. Solder encoder leads on +5V, GND and one PWM input capture pad (A or B).
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Load servo control firmware into the STM32G431 using the USB daughter board
Hi Pat92fr: The user manual for B-G431B-ESC1 on ST website is revision 4. DO you have revision 1 or revision 2 available with you? I want to look into schematics of B-G431B-ESC1. In revision 4, ST has deleted the schematics of B-G431B-ESC1.
Hello QuestforMotion. Yes, of course, and that works quite well. I have just implemented a FOC algorithm using an absolute encoder (14bit) for angular position. My firmware offers several operating modes : position control, velocity control, and torque control. I will make it open source hardware (printed parts) and software. The main drawback of this evaluation kit is the thermal dissipation. Board is getting very hot at maximum torque. I think a forced convection is mandatory. Bye !
Thanks for your quick answer, I appreciate it. That's great! I have some experience programming FOC firmware using the TI Launchpad and motor control evaluation boards, but they are way more expensive (30USD board + 80USD motor driver). So it's amazing to see that there seems to be a viable alternative. Thermal dissipation should be solvable, I guess... Anyway, I am looking forward to checking your implementation of the motor control!
Hi Pat92fr: The user manual for B-G431B-ESC1 on ST website is revision 4. DO you have revision 1 or revision 2 available with you? I want to look into schematics of B-G431B-ESC1. In revision 4, ST has deleted the schematics of B-G431B-ESC1.
Looking forward to hear from you. Thank you.