Sandbox

From Team1370

Revision as of 00:39, 12 February 2006

A workspace for temporary things

Joystick Config

• Control values will range from 0 to 254.

• Each value corresponds to a specific motor speed on the robot. 127 is neutra, <127 is reverse, >127 is forward.

Motion

• Forward and backward motion will be achieved by cycling Joystick 1 and Joystick 2 forwards and backwards at the same time

• Turning will be achieved using a track configuration. Moving Joystick 1 forward at a higher rate than Joystick 2 will result in a left turn, and vice versa for right. Moving left forwards equal to right backwards will result in a 360 degree left turn and vice versa for right.

• The throttle will change the thrust multiplyer and/or additive.

Sensitivity

• Joystick sensitivity is a problem, but there are a few solutions

Linear Output

• We currently operate on linear output, where every joystick value x corresponds to motor value reception y plus or minus throttle setting z.

• Throttle can count as a speed shifter. If we have max and min output value limiting functions, we can shift the throttle to achieve a higher max forward speed and a lower max reverse speed and vice versa if necessary on the fly.

Exponential Output

• I reccomend using exponential output for controlling acceleration. In this situation, every joystick value x is given a value of (1/(127X^2)) + 127 to get y (or something similar). This particular equation will make it so that the robot quickly speeds up but accelerates more slowly as x increases.

Math for throttling

Stick stuff here

if (Joystick = 255)
   Joystick = 254;
if (Throttle = 255)
   Throttle = 254;

pwm = ((Joystick - 127) * (Throttle) / 254) + 127;

The (Joystick - 127) means that the joystick value shifted so that it goes from -127 to 127.

The +127 at the end shifts the system back up to the 0 to 254 range.