Quote:
Originally posted by Al Skierkiewicz
Keith,
We haven't used feedback to limit control at this point. The software just scales back during normal operation and goes to full control when a button on the joystick is pressed. Our "turbo" button is just used on drive control when we want to get somewhere in a hurry. [...] The gear ratios are chosen for optimum torque at the lower speed and are obviously different for the FP motors or the drill motors.
Al
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So are you saying you'd do something like this:
- Set up the gear ratio of a drivetrain motor to be (for example) "60A max before tire breakaway"
- Full joystick push now outputs only a 50% duty cycle PWM signal in each direction (30A limit)
- When you hit the "turbo" button, it would then jump to 100% duty cycle in each direction.
If not, then what exactly are you doing?
Quote:
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Originally posted by Al Skierkiewicz P.S. Although we have considered using our current sense to control software we think it needs a little more work so that the drivers are not confused by the action of the software. Practice, practice, practice is the key.
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You're right... You have to have a LOT of practice time reserved if your program tries to "autopilot" things like speed ramping, or it'll be immediately compensated for by the driver who doesn't expect it.
Man oh man we had a LOT of trouble last year on my previous team with the driver "overriding" the software filtering. <chuckle> Whatever the programmer tried, the driver would adapt to it... Asking him not to do that didn't matter. He wasn't even
conscious of this reaction. Deep down inside he
expected a certain behavior from the robot, and by golly his unconscious body's behavior with the controls was going to make it happen that way!
When the driver started gripping the joysticks at their BASE with a thumb and forefinger, and started slamming them full in each direction, we gave up! We tore
all the filter code out, and simply asked the driver to "PLEASE don't ask the machine to reverse too quickly or you'll blow the breakers"...
What the heck... Although a little jerky at times, the robot ran just fine, and admittedly the code
was shorter.
- Keith