Saturday, February 5, 2011

We need a FUNCTIONAL killswtich...

The killswitch is still ineffective. It will not pass inspection at the competition. I have no idea why on earth it still refuses to turn off. I can follow 5 feet behind it, press "OFF" or hold it in all kinds of ways until my thumb falls off, and it still does not die, even with this new switch with an antenna. This failure to stop resulted in irreparable damage to the ultrasonic range finder. (cont....)

I was testing my gps navigation code, and the robot found a path which placed it's heading directly at a curb. I was carrying my laptop in one arm and the killswitch in the other. When I realized where it was going (about 25 feet away), I started trying to kill it. I was running less than 10 feet behind it, unable to get in front to stop it, doing thumb gymnastics on the off button trying to get it to stop.
It did not.
The magnet sensor box came dislodged from the lid, and the platform continued to try moving forward. I was already mad that the killswitch failed and i would have to hot glue the compass back on, but when I saw what happened to the sonar sensor, I broke. I assumed the killswitch I recieved to put in the platform was a failsafe to prevent this sort of thing.
It was not.
Forgive me if I sound bitter and pessimistic, but right now I'm so mad at myself, I feel like Budd Dwyer:

We need a killswitch that doesn't rely on a signal to turn off, but instead, one that relies on a signal to stay on. If the platform fails to receive remote signal it needs to die right then and there.
The strange thing is that I can turn on and off the relay from like 20 ft away 100% of the time if the platform is stationary, but not when it's in motion.
Oh and i know for sure it's broken, because one of the SMT chips is cracked in half, and I just get a reading of 255 in hyperterminal.

1 comment:

  1. Thanks for your cheering commentary. I have ordered yet another Ultrasonic sensor (perhaps a bulk buy is in order) I have a sure fire kill switch solution. (I used it on my 80 pound robot previously.) It consists of ~20 feet of 18 gauge wire connected to a normally open switch that you must depress with your thumb in order for the bot to run. You will have to chase the robot around with this configuration, but it should be fool proof!