Entry ID #: 9146
Created: Tue, Dec 8, 2020 11:55 AM
My submission for the AutoDesk “Make It Real” Engineering Challenge is the Vex Raspberry Pi Communicator. The Vex platform is amazing; the ease of use and reliability never cease to amaze me. The Raspberry Pi and its community offer networking, access to artificial intelligence software, and speech and voice recognition software, just to name a few potentials. I sought to create a part that would allow reliable communication between the two platforms. The result: a Vex Raspberry Pi communicator. Although the possible uses are only limited by one’s imagination, I chose to demonstrate how it works with an automatic dog feeder. Previously, I used the same concept with an automatic plant carer. There is a YouTube video associated with this which I have attached here.
Purpose of Part in Automatic Dog Feeder:
The communicator allows for the VEX component to receive a signal from the Raspberry Pi to place water and food in a bowl. The Raspberry Pi with a real time clock monitors the time. When predetermined times occur, the Raspberry Pi triggers a pump that fills the water bowl and the Vex microcontroller allows food to pass into the feeding bowl. Additionally, a distance sensor on the Vex apparatus triggers the Raspberry Pi to take a picture of the four legged friend eating or drinking. Lastly, since the Raspberry Pi can access the internet, it is possible for one to feed, provide water, and check to see if the bowls are full when travelling.
Design of the Part:
The communicator, which was originally created in Tinkercad, then exported to Autocad Fusion 360, has three printed components. The first being the base. The base holds the Vex V5 motor, the Vex color sensor, and the breadboard. Next is the hood/top that creates a sealed dark environment that allows for the Vex color sensor to pick up the light emitted from the LED on the breadboard. Lastly, there is a 3D printed arm so the Vex motor can access the button on the breadboard.
How it works:
The python code running on the Raspberry Pi checks is constantly checking the time. When it is the time that the user has previously chosen, the Raspberry Pi triggers a light that is sensed by the Vex V5 system. This will run a motor that allows the food to fall into a bowl. The Raspberry Pi is also connected to a water pump so that it can fill the water bowl. A distance sensor attached to the V5 microcontroller can sense when the four-legged friend is in close proximity. The microcontroller then actuates a motor that pushes a bottom- which is sensed by the Raspberry Pi. The Raspberry Pi then takes a picture, which with further programming wizardry can be e-mailed, tweeted, or live-streamed.
How I used software:
Before using Tinkercad and Fusion 360, I had a general idea of what I wanted to create. I found that using the CAD design tools helped me formulate my ideas and forced me to recognize some constraints that I did not initially recognize. First I brought in a file representing a VEX plate and increased its depth. This allowed for a means to attach the Communicator with screws and bolts. Next, I added rectangular pieces to make the holding box for the sensor and LED. I created the stand to hold the motor and support for Raspberry Pi button. Placing each of these in the CAD environment forced me to pay attention to dimensions so that everything would fit.
Designed in most recent version of Tinkercad (as of 12/7/20), then exported to Fusion 360 (2.0.8749 Windows 10 (19042))
I learned how to use Cad to a greater degree of complexity. This was my first time using Autocad Fusion 360. I learned that Cad designing allows for quicker trials of mechanical ideas. Working on this project has only boosted my interest in 3D-printing. I look forward to creating more robots using 3D-printed parts. Learning to use this software was not only applicable to building the automatic dog feeder- I can also apply this knowledge to my competitive VEX robotics team. Exploring solutions to problems on Cad designing has pushed my bounds creatively, which has beneficially impacted my ability to build and program our robot. I am hoping to pursue a career in something that combines robotics, engineering, and medicine. The ability to design 3D-printed pieces will serve me well in the future.