The first version of the kit robot was designed for the minor 'Smart Manufacturing and Robots' (SMR) on the Hague University of Applied sciences. The robot is designed to offer a low cost as near to an industrial robot as a possible solution for Universities, Colleges and High schools. The progress of version 1 halted at the physical construction of the hand (tool interface) and the wrist due to time constraints.
The design progress stopped when the SMR minor ended. Other subjects on the University took priority. It was clear that the design was far from done as issues arrisen after testing. The main issues where the weight of the robot and getting the motors required with enough torque to operate the robot. Mainly the SKF steel bearings used added incredible weight to the robot, together with a miscalculation of the required engine torque the joints failed to move as designed.
Perspective was given by another robot design project on The Hague University of applied sciences. The assignment was to design a robot that could be used in an educative environment. Not too dissimilar as the first robot. However, the project did not allow for a continuation of the first robot and as such a design from scratch was made. This design relied more heavily on 3D printed parts. A group choice that I personally was not happy with.
In the project, design problems came to light by using FDM printed PLA parts. The project gave a new perspective on both Safety designs and how to make a lighter robot. One of these perspectives was to use Nylon bushings.
Using FDM printed Nylon bushing gave a solution to the weight of the robot as well as a cost-saving by avoiding expensive SKF bearings that were for this project well overdesigned. The bushings are designed to function as an angular contact bearing two are used to constrain all degrees of freedom but the rotation in axle direction.
Other techniques came to light for me such as this technique for a perpendicular joint between sheets material. The image shows a possible join to a 3mm multiplex sheet. Where the previous version relied a lot on glued joints this impacted the flexibility of the design. The new version would introduce flexibility by designing most parts to be replaceable.
The Ultimate goal is to profide a affordable kit robot that universities, colleges, highschools, and makerspaces can use to teach anyone who is intrested robotics. As such I have deviced of a few criteria that the robot should have:
Machines available;
- 150 W BRM laser cutter
- 50 W Epilogue solidstate laser
- Ultimaker 3
- Creality 20 s
- Lathes
- end mill
Materials and platforms currently available:
- Nvidia Jetson TX
- Rpi 4 8 gb
- Various Arduino platforms
- Intel Edison
