Quote:
Originally Posted by KrazyCarl92
Comparing both of your spreadsheets, I see that your first one gives different results than the second. This appears to be due to the fact that you use voltage as a variable in determining the gearbox output torque.
However, I have observed robots which experience voltage drops when initially engaging in a pushing match then quickly recover. This would mean that the second spreadsheet would be misleading for determining traction limits because this only considers sprints, assuming that the traction limit occurs during the initial drop while disregarding the recovery of battery voltage during a pushing match.
For example, a robot may drop to 8V when initially engaging in a pushing match, then within half a second rise back up to 11V and remain there for the duration of the pushing match. Therefore, the traction limit should be evaluated at 11V and not 8V.
Seems like hard experimentation should be explored before blindly trusting any of these models.
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I certainly wouldn't argue with your last statement.
The older first spreadsheet doesn't take voltage drop into account, so the second one should be a better predictive tool. IF there isn't anything drastically wrong with it.
For a robot's voltage to increase from 8 V to 11 V, the wheels have to start turning. That can happen if the tires spin or if the other robot decides to go backwards. In a situation in which both robots are stalled at a dead stop while trying to push each other, I care about being traction limited at 8 V. If it's an option to back up and ram the other robot to develop a bit of wheel speed, or if the other robot might let up for a second to let me gain an inch, then I agree that being traction limited at 11 V could be just fine in those cases.