Search results

Date Relevance Most replies

  1. C

    50mph Razor E300

    Using a Freefly ARC200 motor drive to get around 50mph on an E300 https://www.youtube.com/watch?v=9iJfO7SDEQQ
  2. C

    Drone Surfing

    just need to scale everything by x4 in Solidworks ;-)
  3. C

    Drone Surfing

    The company I work for made a new video that may be interesting to you guys. Might need a new section at ES for aircraft/watercraft hybrids ;-) BuRf6r0LuL8
  4. C

    Xnova 8kw rc middrive first test

    Just as an FYI, I have nothing to do with Xnova motors and I can't say anything about their quality. The design from the outside looks exactly the same as the motors I designed. I stopped selling motors some time ago when I started working on camera gimbals and other flying things at...
  5. C

    Compact Field Oriented Controller, ASI + Grin, limited run

    Same problem here running 1.5.4, don't see "d output".
  6. C

    Lebowski's motor controller IC, schematic & setup, new v2.A1

    Switching losses increase with increasing frequency. There is a balance between switching losses, current ripple losses, and motor switching noise. That balance point is usually between 12 and 100khz...but there are no set rules.
  7. C

    low inductance output stage contruction

    I find it's much easier to preheat the entire assembly on a hot plate, oven, or hot air station to just below a temperature that will start damaging components. Soldering anything massive is far easier that way.
  8. C

    Destroyed! A warning to those using freewheel cranks....

    Yeah, that's the one and thanks for the info. I'd be interested in picking one up depending on the price :)
  9. C

    Destroyed! A warning to those using freewheel cranks....

    Do these have the same dimensions as the white industries freewheel; hole locations etc?
  10. C

    Lebowski's motor controller IC, schematic & setup, new v2.A1

    He already posted in your own thread ;) http://endless-sphere.com/forums/viewtopic.php?f=3&t=38337#p559556
  11. C

    powercroco 135-50 inrunner - 40kW bldc

    Carbon is fine. All the neumotors use it and I've used it as well.
  12. C

    Envia Systems twice the energy density of lithium cobalt

    Yeah..seems like these are really 300wh/kg cells which is still awesome...but they need to fix the huge degradation over the first 10cycles before they can honestly claim 400wh/kg. Still...if 400wh/kg is possible for 10 cycles with these cells..maybe their 2nd gen cells will do it for 100-1000?!
  13. C

    A123 20Ah cells price down to 17.50$ per cells?

    Yeah, you just have to let the video play in the background and jump in when things get interesting. If you are in a browser, just leave it running in a tab. Lots of industry gossip and other things that might be valuable in these videos.
  14. C

    A123 20Ah cells price down to 17.50$ per cells?

    Haha...he really lets us "kids with bicycles" have it at 33mins in http://www.youtube.com/watch?v=RVh47P4h6PY&feature=g-u-u&context=G2ce3ff7FUAAAAAAAAAA
  15. C

    A123 20Ah cells price down to 17.50$ per cells?

    multiple cells in parallel are identical to one big cell.
  16. C

    Belt drive Sprockets on the Cheap!

    Yeah, I'm using the Polychain carbon 8mm pitch belts (12mm wide). I found an old gates patent that had crap for information..then tweaked the design in by eye. Absolutely no problems so far with the belt or delrin sprockets. The hardest part is getting the correct belt tension....I'm using a...
  17. C

    Belt drive Sprockets on the Cheap!

    Man...great minds think alike 8) BTW delrin works fantastic, better than aluminum. I have maybe 1000 miles on the one in the picture.
  18. C

    #$%@$#@ <--- (insert favorite swearword here), IT WORKS !!!!

    if the FET's are off it would be possible measure the BEMF and then activate the sensorless algorithm again after rotor position is known. Since the BEMF waveform is already stored, it shouldn't take but a few samples of the BEMF to find rotor position. I imagine the only time this would need...
  19. C

    #$%@$#@ <--- (insert favorite swearword here), IT WORKS !!!!

    As long as you have a really elegant way to control phase current during fault conditions then some sort of recovery is fine. It would really suck to have a front wheel mounted hub motor lock up hard at full speed!!! Maybe even a fallback to sensorless trapezoidal control if lock is lost?
  20. C

    Joby motor, dc/dc converter, igbt controller, photodiodes

    Luke is right about the motor. The battery management would also be more complex when you get to high voltages. Only when you're talking about running something the size of a car does that make sense. Running a boost converter will also add more cost and complexity and decrease efficiency...
  21. C

    Pushing the IRFB4110's to the limit

    Nothing wrong with current technology. Only thing wrong is in the design area. Everything targeted towards the low end EV market doesn't have enough protection and monitoring software/circuitry and is still based around the most basic motor control theory. Things will change soon, I'm sure of...
  22. C

    Joby Motors Santa Cruz, CA

    WOW, so they will continue to make and sell motors..but no new developments? Very strange :?
  23. C

    Joby Motors Santa Cruz, CA

    Called Joby up and was told "joby motors" isn't out of business but "joby energy" is. They said motors would continue to be sold. The plot thickens?!
  24. C

    Not simple BLDC controller It RUNS! :)

    Starting with the PCB or code doesn't matter worth a darn. The PCB can be designed with all the features in mind, if the code isn't be written to support all the hardware features..that's not at all a problem. When a team works on a project, the hardware guys don't wait around for the software...
  25. C

    Rickys High Power Flexable motor controller

    Ricky, you're not in Christchurch are you?! :shock:
Back
Top