1. 1. Design of 3R Manipulator to Operate in Space Team Members Aniket Shirsat Anandrao Biradar Prasannakumar Ghadage
2. 2. Motivation Design a versatile system that can perform different tasks in inaccessible or hazardous environment for humans. Incorporate various sensors in the system. Implement obstacle avoidance.
3. 3. Methodology Generating the D-H parameters for the robot. Utilizing the Forward kinematics that we get from the D-H Parameters to form the Manipulability Jacobian. Using the Jacobian to perform the following phases o Phase 1: Sinusoidal end effector path . o Phase 2: Reaching a particular spot in space ( spot welding in an space environment). o Phase 3: Avoiding a certain obstacle ( i.e. detecting oncoming debris and assuming a position to avoid the debris. Getting the force and the velocity ellipsoids in each phase. Implementing the simulated MATLAB code into the LEGO Brick.
4. 4. D-H Parameters and Jacobian Matrices d a 0A1 1 D1 L1 /2 1A2 2 0 L2 0 2A3 3 0 L3 0 Forward Kinematics
5. 5. Phase 1
6. 6. Phase 1
7. 7. Phase 2
8. 8. Phase 2
9. 9. Phase 3
10. 10. Phase 3
11. 11. Simulation & Lego ? MATLAB LEGO Curves smoother and continuous Piecewise Linear and jerky No real effects like inertia and are modeled Inertia and delays are present. No gears are modeled Gears come with backlash error.
12. 12. Video
13. 13. Difficulties The most foremost difficulty is getting the dynamics for the 3R case in 3 dimensions. The equations turn out to be highly non-linear and coupled . Thus getting an analytic solution for torque is computationally intense. LEGO is a good tool for educational purposes but it lacks the versatility in terms of motor control. LEGOs dont generate feedback thus errors cannot be reduced hampering accuracy.
14. 14. Solutions & Future scope Get a sturdier frame to mount the actuators. Getting feedback from the sensors ( if possible) and thus making it more precise and accurate. Better modeling of the system. Using a better board like Arduino for interfacing with the computer.
15. 15. Questions?
16. 16. Thank you!