Wow, I was really surprised when I went to DP today and saw the project linked right there on the front page!
Thanks for the comments, they are all well taken.
what would you estimate to be your assembled cost of the BLDC Boosterpack that you designed?
In regard to assembly cost, at the moment I've been hand soldering the first round of boards. This takes a decent amount of time (20-30 min per board) since there are quite a few discrete components (~50) and they are all quite small. For the next batch, I have a solder stencil and we're going to use paste, hand place components and reflow them in a toaster oven, hopefully this will drop the amount of time significantly. I'm not a pro for pricing models of assembly but when I started looking at pricing, I went on the conservative side and figured it woud be $5-$10. Besides assembly, theres cost of components, shipping them all around the place and the tooling for stencils and things like that. Surprisingly, the BOM cost is the smallest part of the pie on how I got to $35. I'm actually surprised how much a static bag and cardboard box costs in relation to some of the other components! In the spirit of open source, I definitely don't want to set pricing in a vaccuum, would be interested to hear everyones thoughts on that but hopefully that doesn't become the focus of this thread.
why "booster" ? I don't see nothing being boosted :) .. maybe you should incorporate ESC into name of your project for easy search
Very true, I'm certainly not boosting a voltage rail or anything like that (although you could probably use this as the power electronics for a boost/buck converter with some creativity). Booster simply comes from "Booster Pack" which is what TI calls add on cards for their LaunchPad kits. Adding ESC is a good point, my goal is exactly that, to make a open source ESC, particularly one that uses the BEMF integration technique instead of the zero crossing
method like a traditional ESC. The other goal is to make it inexpensive and compact so that we can someday see a quadcopter, RC car or airplane with a fully integrated controller + drive(s) all on one board. I really dislike excessive wire harnesses :)
you might want to add ntc to monitor temperature of the board (fets) and another one to monitor temp of the motor
Now that wouldn't be very Dangerous :) Actually good point, only thing that I'll say is that the extra ADC pins are unfortunately consumed by the UART so thats a bummer. I'm hoping the addition of current sense will be two fold, one is for control but also for protection to limit the strain on the FETs and motor.
Would be nice if you share the source files (for pcb/schematic/firmware...), there's not many ESC's out there that are open source so it might go wild fast
All source files are available on github
For my initial post, the forum didn't like me including hyperlinks as a spam protection. I would be great if it goes wild fast (both figuratively and most important literally).