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Unread 15-02-2007, 07:45
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AKA: Robinson Levin
FRC #1648 (The Gearbox Gangstaz)
Team Role: Programmer
 
Join Date: Jan 2006
Rookie Year: 2005
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Posts: 116
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Re: Moving to a point between lights with autonomous

Quote:
Originally Posted by dpick1055 View Post
The problem with attempting dead reconing based off where the lights start is that it is very hard to account for slippage of your wheels and what other robots will be doing. If your alliance has 3 robots going for the rack at once and you hit another robot on your way without some sort of feedback you will have no way of correcting yourself and getting back on target.
Dead reckoning doesn't mean just setting some motor outputs and waiting for a specified amount of time. Dead reckoning in this case refers to the process of estimating the position of your robot based solely on speed and direction of travel and time elapsed since the last known position. The "reckoning" part referes to the fact that you can't get new known position information based on the location of the rack. You can, however, account for wheel slippage by using accelerometers and a gyro, which track absolute--not commanded--speed and heading since you left where you know you were. This system can be very accurate if implemented correctly.

Robinson Levin
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