20.6 Conclusion & Future Work
Accomplishments
Overall, this project went fairly well, but took much more time than expected. With the intention of using TPU for compliant joints, we had expected the work to be primarily analysis and not too much design. However, using film joints took many more trials and design iterations. We were successfully able to create in-plane joints and output the correct path as seen from the analysis. Surprisingly, the legs themselves weigh less than 5 ounces, and the whole bot weighs about half a pound. Another noteworthy feature of our robot mechanism is the length of the kinetic chain. The film joints created were strong enough and durable enough to transmit extremely smooth motion through the whole 4-bar parallelogram and 6-bar leg. The film was also strong enough to support the weight of the electronics used, but the Arduino motor was not strong enough to power the legs under load, and therefore, it could not climb stairs. We had initially sized out a 12V motor capable of powering the bot up stairs, but this was too heavy for the film joints to hold up. Thus, while we were able to complete the 6 legged bot with the right movement, we were not able to complete a true functioning stair-climbing robot.
Future Work
To further improve the stair-climbing robot and achieve full functionality, the film used in the joints will need to be replaced by something stronger, potentially even fabric. Secondly, to minimize weight, a lightweight, properly sized motor needs to be used instead of the beefy greartisan, or small Arduino. Finally, to speed up the tedious assembly, the design should be altered to minimize the number of tiny pieces.
Tips for Future Groups and Lessons Learned
Take motor weight into account.
Design for manufacturing and assembly.
Test the strength of materials used.
Label and organize parts if you have a 551-piece robot.
Acknowledgements
Throughout this project, Connor Hennig, the projects TA, was extremely helpful and pointed us in the right direction with film joints.