F. RRG Conclusions and Future Work

This project demonstrated that is it feasible to create a gripper mechanism capable of retracting to conserve space and still perform the pinching motion to grab objects. All of the project requirements were met. Though the design is not completely optimized, in a situation where the extra space that normal robotic fingers extend creates collision space problems, this design could be implemented to improve usability.

Future improvements to the design would include a replacement mechanism for the sliding rack, increased motor power for gripping strength, optimized gearing, and gripping feedback capabilities.

• As it currently stands the sliding rack on the design takes up horizontal space that could be completely eliminated with a scissor-lift mechanism. This would allow for the pure horizontal motion that is needed. While the rack always inhabits the same horizontal space, the expanding scissor-lift mechanism would only take up the horizontal space needed at that moment. The rack was used in this scope for proof-of-concept of the main mechanism and to reduce the friction load on the motor.
• The motor that powered our mechanism was able to provide enough torque to drive our system and grip a full soda can. To remove this limitation the motor would have to be replaced with one that has a higher torque capability.
• If the motor torque is increased it would also be necessary to replace the materials, especially for the gears. Here we used acrylic gears for rapid prototyping, but those could shatter if the motor is too powerful. Likely all of the materials would need to be upgraded to handle stronger torques.
• One last implication of a stronger motor would be that the device could crush objects unintentionally. Here one could implement a sensor feedback system as used in many current grippers to analyze gripping force in real time to grab an item while not crushing it.