www.ti.com They have app notes for making brushless controllers with their processors. Includes a lot of theory too. I have downloaded them and put them on a CD for my own use. Andy Sean Breheny on 09/14/2000 06:19:21 PM Please respond to pic microcontroller discussion list To: PICLIST@MITVMA.MIT.EDU cc: (bcc: Andrew Kunz/TDI_NOTES) Subject: [OT]: Helicopter stuff I've never had so many threads going on the list at once, so picking a subject is a bit confusing :-) Thanks to all those who replied about encoders. We were planning on upgrading our motors soon, so at this point we are debating whether to go with the current motors/better encoders, OR switch to brushless motors (to get beter power/weight ratio and eliminate the need for encoders, since we only need to control speed, not position). We weren't able to find (in my short web search) encoders which were light enough yet could tolerate as much shaft play as we have. I don't think that flexible shaft couplings are the answer because we have considerable up/down shaft play (axial play?) SO, my question is, where can I get a tutorial on driving high power (100W and greater) brushless motors? Are there existing brushless motor controllers which are small,light weight, and accept an input signal which can be correlated to output speed to better than 5% (preferably direct digital serial or parallel input)? Thanks, Sean -- http://www.piclist.com hint: PICList Posts must start with ONE topic: "[PIC]:" PIC only "[EE]:" engineering "[OT]:" off topic "[AD]:" ad's -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics