Remote Kill Switch

[Ozuru]

Originally Posted by jvriezen

An even better safety approach is a 'dead man' switch. This requires a person to continuously hold a switch in the pressed position for the robot to operate. Of course you couple this with a policy that you never jerry rig the switch to be held other than by a human watching the robot.

Basically every push lawn mower has one of these on the handle, and every riding lawnmower has a seat switch that does the same thing (at least when the blades are spinning.)

Update: Clarification: I agree, driving in the pits is not appropriate. My suggestion above is more for driving in the shop and could even apply to driving on a practice field, which is more danger prone than a real field. Seems like it would be a good idea to have a driver station setting that allows you to invert the space bar, and require that it be pressed when enabling and result in a kill if released while enabled.

I kind of feel that a dead man's switch is kind of extreme for something that already has so many security precautions into place. I wouldn't trust myself with a dead man's switch that would deactivate our robot during the match due to the simple fact that accidents happen and if, for some reason, one would happen during the match, we have the ability to 1) slam the spacebar or 2) press the giant emergency stop button.

[jvriezen]

Originally Posted by Ozuru

I kind of feel that a dead man's switch is kind of extreme for something that already has so many security precautions into place. I wouldn't trust myself with a dead man's switch that would deactivate our robot during the match due to the simple fact that accidents happen and if, for some reason, one would happen during the match, we have the ability to 1) slam the spacebar or 2) press the giant emergency stop button.

The dead man switch would not be needed during a match. In that case you already have three team members at the driver station and refs and FTAs all looking out for your bot, as well as a mostly contained playing field.

The dead man switch approach would be instituted in your shop/practice area at home (based on your perceived need for that level of safety) and could possibly be used at an event practice field where there are lots more people around often without field walls protecting them from bots.

[philso]

A dead man switch would have to be implemented correctly, tested thoroughly and the users trained properly and thoroughly to ensure that it serves it's intended purpose. Otherwise, is a form of false security that creates yet more complexity with little value.

It is a fair bet that FIRST put a lot of time and effort into designing and performing validation testing on the E-Stop function integrated into the FMS.

[MrRoboSteve]

In scenarios where we might need to stop the robot quickly, an operator stays by the driver station is trained to hit the spacebar if things get out of control. Hard to see how a dedicated button improves on that.