17.4 - Implementation

Design Details

Our project would not be successful if it were not for the multiple iterations we designed and tested along the way. In this section we will show our hardware, electronics, and software development that is implemented within our final build. 

Hardware:

Mechanism Fabrication

We laser cut the links of our 4 bar mechanism out of acrylic and built the mechanism with 6mm shafts and bearings. Furthermore, we also constrained the non-moving components with screws and nuts so that we don't introduce other DOFs. The end of our mechanism is a custom made steel piece that was manufactured in the TIW. Due to lack of torque output from the motor, we designed a 49:1 gear system with acrylic using the laser cutter and attached the system from the Pololu 37D Gearmotor to the crank link in our four-bar mechanism.

Figure 1: Picture of the 4 Bar Mechanism On A Test Platform

Figure 2: End Effector 

Figure 3: Gear System

Figure 4: Pololu 37D Metal Gearmotor

External Hardware Components

We utilized the TIW's 3D printers to make our can-holder. The key to this design is the tolerance between the can and the holder, as we needed to make room for rubber stripping that prevents the can from rotating our slipping when the tab is lifted. 

Figure 5: Can Holder With Rubber Strips Between Can And Holder

Since our mechanism is being held up vertically by 2 acrylic sheets, we created lower support pieces that we stacked so that the mechanism would not have the risk of falling. 

Figure 6: Mechanism Supports

Electronics:

For electronics, our mechanism is powered with a AC to 12V DC power supply that fits the needs for the motor we are using. We controlled the motor using L298N motor driver and pushing code to activate the motor using and Arduino. 

Figure 7: Arduino, Motor Driver, and 12V Power Supply

Software:

For our software, we needed the motor to run continuously, so we developed Arduino code that turns on the motor at highest speed for a long time so that multiple cycles of the position profile can be made. 

Figure 8: Arduino Code To Run the Pololu Motor