evan kim

final project: designing modules

November 2, 2020
With more electronics assignments under my belt from the past couple of weeks, I have gotten much more familiar with how to design, print, and solder PCBs. This is important because a good chunk of my project will involve electronics.

This week I wanted to do additional research and start designing the modules that I would need for my final project: the launcher and the dropper. I have had a rough idea of how both of these modules would work, however, I still haven’t done a deep dive into the feasibility of these implementations. I planned to create the launcher during outputs week and with outputs week just around the corner, this was the best time to do some research on what was needed to make a successful launcher. Additionally, if I have extra time during the outputs week, I plan on also creating the dropper.
For the launcher, I had many different ideas ranging from a device like a ball cannon for football, to a motor that would simply punch out the treat, to a slingshot. After discussing with my section instructor, I decided to dive a little deeper into the slingshot design for a couple of reasons. The first is that the first two ideas would likely break the treat, increasing the chance that treats would jam my device. Secondly, I don’t need much force, as I’m only trying to launch my treat a couple of feet forward. Given that this device will likely sit on the top of a table, projecting a treat a couple of feet forward should be more than enough.

For the design of the slingshot, I could go down a couple of different alleys. The first was using an adjusted rack and pinion. The pinion would be custom made (likely 3D printed) where a section of the pinion would have teeth while the rest of the pinion would have no teeth. This approach would use a stepper motor to load the slingshot and then release the slingshot when the smooth side of the pinon made contact with the rack. This idea seems very doable and I would print out the rack and pinion. However, one downside I see of this approach is that it may take up lots of space and cause my housing to be big and bulky.