I doubt he’s on the forum. He’s moved away from the DRV8302 in his designs, so it can’t be that bad. (Crossing fingers for eventual reliable FOC).
Looking at his stuff makes me realize I need to be more ambitious with being a robotics student LOL.
Looks kinda like he’s trying to build a better, faster Boosted. BMS looks interesting as it’s tailor-made for 12s LiFePO4.
I’d be very interested in an ESC designed specifically for FOC, especially if it can handle high amps better than the VESC. Amazing to see guys do this kinda work in their free time and share their design open-source.
Thank you everyone for inviting me to this forum, and thanks for all the positive comments! Sorry for taking so long to reply to this thread, school has been very busy for the last month.
First, a bit about me: I’m a student at MIT and I enjoy designing and building electromechanical systems. I was originally developing an ESC and BMS just for my own skateboard, to build a skateboard with fully custom parts. Over the last year, however, they became more independent projects. Since there seems to be quite a bit of interest in them in the DIY community, I am interested in developing and releasing them to the DIY community for others to use. This will take some more development to make them work with different system requirements; I have a rough timeline below.
Here’s a small preview of the two boards, the ESC (“Infinity”) and the BMS (“Battman”). They’re still under development, so some of these specifications may change as I do more testing and iterating.
Supports 4 to 12 cell LiPo and LiFePo4 battery packs
100A continuous, 150A peak discharge current (may change)
Cell voltage monitoring and ~100mA balancing with LTC6803 IC
Bidirectional current monitoring with overcurrent protection and SOC tracking (planned)
Boost converter circuit with adjustable voltage for CC/CV charging at ~3A
Pre-discharge circuit to limit inrush current
External push button (momentary) switch to turn on BMS and rest of system
Complete shutdown to preserve battery when not in use
STM32F3 with UART, I2C, CAN communication and WS2812 LED support
GUI for configuration
Flash memory to log battery usage data during rides
Optional CAN communication with Infinity ESC for smarter protection (planned)
3.5"x1" PCB size
As these are personal projects, I have to balance the time I spend on them with schoolwork and other things, so it will take a while before they’re ready for use. Still, I’m spending quite a bit of time on them, as well as working with a few friends to develop various aspects in parallel. I’m estimating a few more months of development, so early 2017 is what I am aiming for right now. Infinity is a little further along than Battman, so it might be ready first.
Any questions and comments are appreciated, and I’ll definitely post more details and any important updates here. Stay tuned!
Thank you for joining and sharing your work. Both the esc and bms are very interesting, especially the BMS as I have not personally seen one as powerful that is that small. That PCB size seems to apply to 10A discharge BMS.
Would you consider integrating a receiver or Bluetooth module in either the BMS or ESC? I forgot what built in radio the Vesc 6.0 will have but doing something similar would be great.
For the BMS could you add a little fuse standoffs so we don’t have to have a separate fuse unit.
I have considered integrating a Bluetooth module into the BMS and ESC, but I decided that it would be better to design an external module that would be plug and play into one of the JST connectors. This way, I can keep the boards compact (wireless modules tend to require many parts + antenna space) and people who don’t care about having Bluetooth don’t have to pay for the extra components.
I do have surface mount fuses on the BMS right now (a few in parallel). If they turn out to be problematic at high currents I will consider switching to standard fuses, but it could be difficult with size constraints.
I have actually seen the DieBieMS before, but I did not know it originated here. We seem to have a lot of features in common, it would be awesome for both projects to co-exist in the community.
I think this is a good decision - I personally use XBee and am looking forward to giving your designs a try and would much rather have a serial connection than to have to hack in a nonstandard radio.
Thank you very much for open sourcing the project!