We all know what velocity is, but how do you design a robot to go at a definedvelocity? Of course you can put a really fast motor on your robot and hope that it will gofast enough. But if you can calculate it you can design it to go your requiredspeed without doubt, and leave the rest of the motor force for torque.
So how to do this? For an example, suppose you have a wheeled robot that youwant to run over old people with. You know from experiments that old people canrun at 3 feet per second. So what motor rpm do you need, and what diametershould your wheels be, so they cant get away or hide their medicine?
MOTOR
MOTOR1
Conceptually, every time your wheelrotates an entire revolution, your robot travels the distance equal to thecircumference of the wheel. So multiply the circumference by the number ofrotations per minute, and you then get the distance your robot travels in aminute.
Velocity = circumference * rpm
Velocity = diameter * pi * rpm OR Velocity = 2 * radius * pi * rpm
Velocity = diameter * pi * rpm OR Velocity = 2 * radius * pi * rpm
Forexample, if your motor has a rotation speed (under load) of 100rpm (determined bylooking up the motor part number online) and you want to travel at 3 feet persecond, calculate:
3 ft/s = diameter * pi * 100rpm
3 ft/s = diameter * pi * 1.67rps (rotations per second)
diameter = 3 ft/s / (3.14 * 1.67 rps)
diameter = 0.57 ft, or 6.89"
3 ft/s = diameter * pi * 1.67rps (rotations per second)
diameter = 3 ft/s / (3.14 * 1.67 rps)
diameter = 0.57 ft, or 6.89"
https://www.facebook.com/merchantofdeath777
No comments:
Post a Comment