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Unread 08-04-2004, 16:58
Biff Biff is offline
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AKA: Tom Cooper
#1227 (Techno Gremlins)
Team Role: Mentor
 
Join Date: Jan 2004
Location: Grand Rapids MI
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Re: Joining 2 dif. motors

Quote:
Originally Posted by Matt Adams
In general, I've found it much more efficient to combine a pair of motors, and then run this combined set out via some sprockets to the wheels. This ensures that one wheel won't ever try to run a bit faster than the others. If you try to run them individually, your motor torque and speed outputs vary as the speed of your robot changes. Fortunately, the Chips and Drills happen to have roughly the same trip points when matched at free speed, which is why I'd imagine a lot of people don't notice it.

Matt
What we did this year was to link the drills with out gearboxes to a main shaft from the Cims, This was done at 1:3.3333 (a 9 tooth on the drill and a 30 on the Shaft connected to the Cim) This was then reduced twice 1:4.5 to the 14 inch wheels. This gave us 1:67.5 if you start at the drill motor. Checking the current with wheels up and runnning full tilt, we had almost the same current at the Cims as the drills. Also we installed the drill motors facing the same way, the Cims oposide and as luck would have it the drills were in reverse, with forward for the bot being backward for the drill motors. This was left this way to help keep the bot from doing wheelies so easly and to make towing the mobile goal backward the most powerfull. We never had the weight left over to make a decated holder for towing so it didn't happen very often. With the exception of the time our arm was extended and dropped into the moble goal. One of the drills would run a little hoter than the other, but I suspect this was due to being dropped duriong he build and having a little more friction on that side do to chain. It may also be do to the not having room to mount the Cims facing the same way.