Electrical System

We are using two VEX CIM Motors to power the two flywheels that act as our launching system. We determined that these motors fit our design constraints through a MATLAB script we wrote that calculated the necessary torque and RPM of the motor to launch and spin the ball at our specified values. The output plot of the motor's Torque-Speed chart and where our requirements fall on that curve are shown on the left. 

With the ratings of our motors, we looked for motor controllers that were rated for 12V and a continuous supply of 40 amps. We decided to use motor controllers that are rated for 10-55V and 60A. Each motor requires its own motor controller. We chose to use motor controllers for our system because our system does not require the full capability of the motors and we wanted to control the rate at which the motors ramped up to our target RPM to mitigate any torques applied on our support structure from the sudden jerk caused by the motor acceleration.

We are using a Nema 17 Model Linear Stepper Motor with an 11 in. lead screw in order to power the pusher system that autonomously feeds a football into the flywheels in the same orientation every time without human input. The stepper motor is wired to a TB6600 Microstep Driver that controls the input current to the stepper as well as the number of pulses per revolution based on the step count selected. An Arduino powered by a portable 12V 5200mAh battery is connected to the microstep driver and hosts the code that manipulates the stepper to oscillate the pusher component forward and back to feed a football into the flywheels.