At the beginning of this week, I contributed in presenting during the Interim Demo on Monday and Wednesday. Our original motor control board broke down and the temporary board suddenly got delayed in shipping, but I was able to help set up the replacement board for Wednesday’s demo once it came to give the staff a better view of how the DC bike motors will be operated. Following the demo, I started to build the base using PVC pipe, PVC sheet, and thinking about the gears to buy. However, due to a limited timeline and not wanting to take any risks of building a rotating base that may potentially break down or not work, I helped decide to use a robot for the base instead. The robot has its own motor controls and wheels, meaning that it will be able to be mobile and make it easier to rotate as well as travel around if our launcher’s range is limited.
My progress was initially behind, but after shifting to the robot base, it makes the project timeline more achievable. Rather than having to rely on completely building a base from scratch with gears, ball bearings, and stepper motor that may not even work until it is finalized and tested, I believe that having a robot makes our project completable in the coming weeks since it is already a built structure. The robot needs to have its wheel motors coded and have the launchers and camera reintegrated on top of it.
Next week, I hope to rebuild the launcher onto the robot base once it arrives. Currently putty is being used to stabilize the wheel attachments on the DC bike motors, so I plan to use some form of press fit + strong glue to make it better. Following the physical build, I hope to help Miles with the motor control code for both the launcher and the robot. The CV is basically finished so motors and overall integration are the biggest priority.
With a temporary launcher built and applying low wattage (around 10% of the motor’s max of 350W), the ball launches around 2 feet. Also, the temporary putty with the wheel attachment seems to be stable when launching a ball at low power. The 45 degree angle attachments for the base of the motors also hold up and so far gives the desired launch distance as calculated by my physics. With all of these temporary and low power implementation, I am confident that in the coming weeks when better parts arrive and I can finalize the build, the ball will be able to launch 20+ feet at 45º as proposed. When the structure is completely built, I will apply max wattage to the motors and see how far the tennis ball launches with respect to a 20 foot marker/tape on the ground. If it does not reach 20+ feet, then adjustments such as reducing/increasing the angle of launch or using different materials for the spinning wheels may be tested for example. If these alternatives do not work, then testing robot mobility to reach a target rather than overexerting a launch distance is another option.