Comments on: Harpy – Sumo Bots 2009 http://www.geekshavefeelings.com xo wang Wed, 30 Jun 2010 16:23:51 +0000 hourly 1 http://wordpress.org/?v=3.0.1 By: GHF http://www.geekshavefeelings.com/projects/harpy-sumo-bots-2009/comment-page-1#comment-343 GHF Tue, 02 Mar 2010 11:54:31 +0000 http://www.geekshavefeelings.com/?page_id=105#comment-343 Actually, I agree completely. I adored my Sabertooth 2×10A when I first got it. What I liked most was just how incredibly sturdy its construction was, and how much thought they had put into making it usable and reliable (DIP switches, terminal blocks for PWM, huge heatsink, etc.). It was enough for me to get a second unit, the 2×25A. I'm not sure if it was a design flaw or I got a bad unit, but it simply never worked. As we tried to experiment with it to get it to work, suddenly the battery leads going into it started smoking and then caught fire. As it turned out, one of the FETs' leads were in contact with an indentation in the heatsink and shorted out the battery. So from there on, I used the 2×10A with far oversized motors, which would trigger overcurrent protection on the Sabertooth whenever I accelerated. So there, you're absolutely right, the Sabertooth really is excellent, and there was no intrinsic fault with it; I was just using it for more than it was designed for. That's why the next iteration was supposed to use Victors, even if that would be too much. Actually, I agree completely. I adored my Sabertooth 2×10A when I first got it. What I liked most was just how incredibly sturdy its construction was, and how much thought they had put into making it usable and reliable (DIP switches, terminal blocks for PWM, huge heatsink, etc.).

It was enough for me to get a second unit, the 2×25A. I’m not sure if it was a design flaw or I got a bad unit, but it simply never worked. As we tried to experiment with it to get it to work, suddenly the battery leads going into it started smoking and then caught fire. As it turned out, one of the FETs’ leads were in contact with an indentation in the heatsink and shorted out the battery.

So from there on, I used the 2×10A with far oversized motors, which would trigger overcurrent protection on the Sabertooth whenever I accelerated. So there, you’re absolutely right, the Sabertooth really is excellent, and there was no intrinsic fault with it; I was just using it for more than it was designed for. That’s why the next iteration was supposed to use Victors, even if that would be too much.

]]> By: BSO Builder http://www.geekshavefeelings.com/projects/harpy-sumo-bots-2009/comment-page-1#comment-339 BSO Builder Sun, 24 Jan 2010 22:24:47 +0000 http://www.geekshavefeelings.com/?page_id=105#comment-339 Actually, on rewatching those videos, it seems like someone just had driving issues-- turning the wrong way, etc. Actually, on rewatching those videos, it seems like someone just had driving issues– turning the wrong way, etc.

]]> By: BSO Builder http://www.geekshavefeelings.com/projects/harpy-sumo-bots-2009/comment-page-1#comment-338 BSO Builder Sun, 24 Jan 2010 21:55:17 +0000 http://www.geekshavefeelings.com/?page_id=105#comment-338 "The motor controller is unacceptably unresponsive and underpowered," you say. Our team from Upstate New York used the same ESC, the Sabertooth, and found it to be extremely impressive in immediate power delivery, regenerative braking, incredible agility, and the added bonuses of exponential and channel mixing. We won 3rd place at States 2009 due to other issues-- the Sabertooth is an excellent ESC. Don't go ragging it. “The motor controller is unacceptably unresponsive and underpowered,” you say. Our team from Upstate New York used the same ESC, the Sabertooth, and found it to be extremely impressive in immediate power delivery, regenerative braking, incredible agility, and the added bonuses of exponential and channel mixing. We won 3rd place at States 2009 due to other issues– the Sabertooth is an excellent ESC. Don't go ragging it.

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