As we decided to dedicate every Monday, Wednesday and Friday of the two months we have available (before we have to return to university to start the new academic year), we didn’t want to spend too long designing the robot. Of course, as we had limited resources, the robot’s design was always going to be simple. However, we wanted the chassis to be one which would allow us to easily change up the layout of the robot, without needing to cut out a new chassis. Our initial sketches included a rectangular shaped base – the size of an A4 paper – on which we would mount the battery, the Arduino UNO, the MD25 and the brackets for the EMG30 Motors.
Two smaller pieces of MDF will be attached to this base, creating shelves. The first shelf will be at height of 50mm from the surface of the base for the first level, and the topmost shelf at a height of 50mm from the surface of the first shelf. A Raspberry Pi, Breadboard and Webcam will be mounted to the first shelf, which is slightly smaller than the base to expose the Arduino but long enough enclose the battery. The topmost shelf is only a fraction of the length of the base, about 50mm in length, as this will only hold the fuse holder and the switch.
The shelves are to be held in supported with threaded rods and held in place using nuts and washers. We initially wanted to use M3 threaded rods, but decided that M4 might be a bit more stable.
This sketch was then used to design a model for the robot on Solidworks. By using this design, we ordered in components and parts accordingly and prepared to start building. As we had completed a robotics project in our last semester, we were able to loan the RD02 Drive Kit from our lecturer to use for our project. We also loaned the lead acid batteries, and the Banebot wheels from him. We were trying to make this as cheap as we could, and tried to source out as much as we could either online or at shops nearby. However, we for the first couple of days, we had some difficulty finding M3 and M4 nuts, washers and bolts. This delayed us by a few days, but whilst waiting, we cut out the chassis, the shelves and also wired up the electronics so that we could test the MD25.
We used the following guide to wire up our drive kit, but included an XT60 connector between the battery and the fuse:
List of components:
4 Male to Male Wires
4 Male to Female Wires
12V 2Ah Lead Acid Battery
On-On Toggle Switch
Black and Red Solid Core Wires