Design Evolution Journal
Week 1-3: Building the Robot
Week 1-3: Early Stages of Building
In the very beginning, our team had a very clear idea of what chassis we wanted(due to our observations - more info on the "Our PBL Project" page). We listed positives and negatives and even planned a strategy before we built the robot. These strategies came largely in part with the fact that the field was very convoluted this year and we wanted to be a good cycling team. When the parts arrived we went to work almost immediately. We would work every Monday, for about 3:30(hours: minutes), Wednesday, and even come on the weekends to help get it done.
Week 2: Chassis
Our chassis is constructed from GoBuilda parts(namely the two 13-hole U-Channel, two 11-hole U-Channel, and one 216 mm GoRail) and we are using mecanum wheels because they provide the greatest net benefit when it comes to general driving and control(more info on the "Our PBL Project" page). Although it is harder to code these wheels, we decided it would be worth the extra effort. We used 4 motors connected to separate wheels that are controlled by bevel gears. This allowed for optimal movement, power, and looks while keeping the structural integrity intact.
Week 4: Problems We Faced
Of course, this came with its fair share of problems. For starters, the company we chose, Go Builda, lacked materials that were compatible with others making attachment creations very difficult. Building the robot also took a long time. We had started relatively slow, and missing pieces were a big issue. The continuous ordering of the materials caused many problems: a halt in building, less progress, and just low morale.
Week 5: Attachment
Our initial robot design included two parallel linear lifts on opposite sides of the robot and a claw-like arm. The lifts were from a viper 4-stage kit and were connected by a Low U-Channel. The claw was operated by a servo and was designed for cycling. We also had plans for additional attachments, such as a suction/intake mechanism for grabbing cones and a 360 degree movable base for efficient cone transfer.
Week 6: Problems With Attachment And what We Did to Combat Them
During Week 6, we encountered problems with our robot's attachment. The motor placement and string rigging were incorrect, causing the attachment to be slow and not rise at all. We also found that the suction wheels got stuck when trying to stack cones. We considered modifying the structure or removing the suction mechanism altogether. Ultimately, we decided to remove the suction mechanism and focus on fixing the wiring issues.
Week 7: Finalization
In Week 7, we finalized the design of the robot. We replaced the two linear lifts with a single lift in the middle of the robot, which made it lighter and faster. We also changed the suction mechanism to a wide claw, which provided the same functionality without the potential for getting stuck. As a result of these changes, our cycling ability improved and we were able to cycle 8 cones in a minute and fifteen seconds. We also made aesthetic improvements to the robot, adding 3D-printed parts for a more polished look. Overall, the robot is now ready for the challenge.