As you can expect, I'm relatively new to the Arduino scene. I have a BSEE with a focus in small circuit design and programming in c,c++,c# was a hobby of mine growing up.
My goal is to learn about microcontrollers, motors, and parts assembly while being productive with my efforts at the same time. This wasn't difficult as my wife is starting to take Tennis lessons from me and a Tennis Ball Machine would combine all of the mentioned subjects. I'm drawing everything up in Autodesk Inventor and the wiring schematics will be done in CADSoft or Visio. I am not afraid to 3D print any enclosures or structure pieces if necessary.
Requirements: - 2 spinning vertical wheel design - Tennis ball must travel up to 80mph from machine- I may use it for myself as well - Enclosure must oscillate 15 degrees left/right and up/down - Must be portable and run on rechargeable batteries - Light weight (max 40lbs) - She may want to bring it out herself. - Remote control of at least 80 ft - length of tennis court - Controller is its own part. I do not wish to have a phone or computer as the controller for these parts could change while a dedicated controller would not. - Any wireless communications method is permitted but nearby signals should not interfere with range/quality of signal - Motor must be of varying speeds to allow for top wheel RPM to differ from bottom and using the remote control, increase/decrease rpm's of top & bottom motors independently
I am not here for guidance on how to physically build the structure. Instead I'm here for the electronics controls portion and motor selection. Which parts to buy and how to implement.
Research: I've done an extensive bit of research already. I know that I can build a gearbox to increase torque coming out of a motor but I wish to maintain high RPM due to the ball speed requirement. I understand the wheel RPM will decrease as the ball is compressed and passed through the opening between the wheels and that electric current draw is the main reason for battery drain. This is due to the torque required to "spin-up" the wheel from a lower RPM to the set point value. I may need to drive the motors with a separate single power supply (some kids toys have ideal rechargeable batteries in them such as the cars/bikes that are motorized).
I assume that a DC motor is best for the rotation of the main wheels, while a stepper motor would be best for creating the oscillation requirement of turning the contraption 15 degrees left/right/up/down.
A good starting point for me is which parts should I be interested in from Arduino and other companies interfacing with the Arduino as well as which motor would best suite this project. I'm a huge fan of math and physics so if you wish to provide, please do not be shy.