Quote:
Originally Posted by JamesCH95
The robot has been shipped to another regional, but I can make a reasonable guess of around 25lb-ft
|
25 ft-lb = 4800 ozin at arm => (4800/380)/2 = 6.32 ozin at each motor
From the motor curves for RS775:
Code:
RS775 @ 12.0 volts:
oz-in Nm rpm rpm% amps watts out watts in eff%
6.3 0.045 12272 94.4 6.6 57.3 78.6 72.9
12,272 rpm at motor = 194 degrees/sec at the arm.
A bit fast for the top end, but motors running nice and cool.
Throttle it down to 90 degrees/sec by reducing the motor voltage:
90 degrees/sec = 15 rpm at arm => 15*380 = 5700 rpm at motor
Code:
RS775 @ 5.9 volts:
oz-in Nm rpm rpm% amps watts out watts in eff%
6.3 0.045 5700 88.7 5.6 26.6 33.5 79.5
Still running cool, and the voltage is in a reasonable range for control.
How about stall?
Code:
RS775 @ 0.7 volts:
oz-in Nm rpm rpm% amps watts out watts in eff%
6.3 0.045 0 0.0 4.9 0.0 3.3 0.0
Very reasonable 3.3 watts dissipation.