In this project, we have created a tennis ball-collecting robot. We based our project on our last year’s project where we created an auto-navigation robot with the ability to identify a tennis ball. We have started our project by trying and testing different mechanisms that will use us to catch and lift a tennis ball. We went from super simple and light construction made of thin wood and finished with a light stable system built from aluminum M4 screws and 90-degree aluminum adapters.
In our next step, we started to implement our electronic needed circuits. In the first step, we learned about the Jetson-Nano GPIO header and the way we can control it. After we learned that, we started our tries to rotate a simple DC motor using the Jetson. To do that we wired up the robot with another wire that goes to the motor driver, and we manipulated our basic servo motor to match our needs. After a few tries we understood that we needed to use a motor driver to use the GPIO and keep the Jetson safe. After manipulating the motor as we wanted, we started to test a few picking methods. Our first basic method was called “Rotating door”. In this method, we are simply trying to rotate a tennis ball up on a ramp into a collecting sink. On this try, we understood that simple DC motors were too weak for us, and we wanted to use servo motors. After a not-good-enough try, we found a construction that matched our needs.
In the last part, we have implemented the code parts that control the whole system. The code system controls the motor position during the whole motor movement, control the speed of the robot according to the distance estimation from the tennis ball, and the most important part, synchronizes these two movement and motor position.