Prototypes Generated By the Viral Solutions Team:
Finger Design Iterations:
Iteration 1:
:
Iteration 2:
Iteration 3:
Iteration 4:
Final Iteration:
Original Test Rig:
Motor Wiring with Updated Test Rig:
Current (Final) Design:
Simulation Results:
First Order Step Response Test for Our Motors:
Root Locus to Obtain PD Controller Gains for Finger Position:
Prototype Fabrication and Sub-System Integration:
The prototype was fabricated using all 3D printed material. This included the fingers, the palm, and the “forearm” to which the hand was mounted on. The “forearm” was essentially a stand in which the motors were mounted to be able to control the movement of each of the fingers.
Multiple subsystems were required to be integrated together. The motors had to be calibrated and attached to the forearm piece in order to control the movement of the fingers. The data glove was not physically integrated into the forearm and hand assembly, but it was used to wirelessly transmit data from the flex sensors to the hand to get the fingers to move according to the movement of the data glove operator.
Results from Prototype Testing:
The results from the tests that we completed did not have a major impact on informing subsequent iterations of our design. Our group’s work came down to nearly the final day of the semester prior to presenting our prototype, and the majority of the tests that we ran based on the prototype that we had at that point met the standards that were laid out in our original Prototype Specifications Report. There were some tests outlined in the original report that could not be completed due to the time constraint, so that is how our group would proceed if we were provided with more time to complete our project.
Current Design – Prototype Specifications Report
Based on the results of prototype testing, our current design meets many of the specifications as laid out in our original Prototype Specifications Report (found under the “Archive” tab) but not all. For example, the current design meets the specifications in the categories of finger length, cost, weight, length of arm, and distance from data glove. The finger length and the length of the arm were confirmed to meet the specifications by measuring them with a ruler. The cost was confirmed using our running budget, and the weight was measured using a scale. The distance from the data glove was measured to be 10 feet which was our upper bound goal, and was measured by slowly moving away from the signal’s receiver and observing when data was no longer transmitted. On the other hand, our current design does not meet the original specifications of pinch strength, degrees of freedom, reaction time, and load capacity. Tests were not able to be performed for pinch strength, reaction time, and load capacity due to time constraints as our group chose to prioritize having a prototype that was capable of movement rather than attempting to complete all specification tests that perhaps would not have been reliable based on the current prototype. The degrees of freedom specification was not met due to the need to use the smaller of motor types that we had, as the quadruple H drivers that we were working with could not be used with the larger motors.