Work Night 5.9.19

Work Night

Date: 5.9.19
Location: Logan HS
Time: 5:15-7:15 PM
Goal: Change over generators on the heel strike simulator (limb tester) and work on EurkaFest PP.
Students: Paige, Caitlin, Tanner, Seth, Thomas and Alex.

The work night and week leading up to it was mostly positive steps for the team as we progress toward EurekaFest.

We finally finished the essential testing of different generator outputs and have come to the conclusion that the 18 V generators (as a reminder we are using stock DC coreless motors as our generators) give us the highest output for current and efficiency. The new 12 V motors have a stronger gearhead that will withstand the torque placed on them from the tester better, but the output is lower than we anticipated. These were the new motors we ordered from India which looked very promising specification wise on paper, but did not test as well as the 18 V motors. The only way we could find out if they would work well was to test them.

We also wanted to try to switch the 8-1 gearheads to the 18 V generators but they would not swap out as the pinion gear inside was not the same size and had a different gear pitch. So we are going with the lighter duty 8-1 gearhead. We have changed over our heel strike simulator to demonstration mode now which will not load the limb as much and should be easier on the gearing. It is much quieter running now as the knee joint does not lock out. We still can demonstrate outputs using an oscope.

During this process we tested out a variety of spring combinations to determine if different spring strength would make a large impact on our outputs. We came to the conclusion that is does make a difference but the size spring (9 kg / 20 lbs) we are currently using gives us the best output without stressing the components.

We spent some time cleaning up connections on the tester and making things look better. Alex is finishing up a LED display that will light up when certain voltages are run into it. This will give our audience a visual other than just saying we are now charging a 1000 mAh battery.

We are working on the our presentation and Paige is organizing who will speak on each slide. Caitlin provided some more information on sustainability and we found out more information on recycling motors that we did not know about. The rotor in a motor is very valuable as far as recycling is concerned.

Seth and Tanner worked on the conceptual design for the next generation generator system. They are working with a local mechanical engineer on it. Tanner also updated our finances.

Austin has the software program in order and just needs to document it for patent purposes.

Next week is final exams for our seniors so work time will be cut back to allow them time to prepare. We will still spend some time getting ready for our May 22nd media day.

Austin and Paige getting the tester ready for painting.

Tape added to protect the electronics of the tester.

Primer coat is going on in our finish room at Logan.

Almost done.

Paint job finished.

The numbers on the springs indicate how many pounds each spring is.

Paige doing wire management on the tester.

Seth and Tanner working on next generation design.

Alex working on a LED display for the a visual representation of our electrical output.

Chart on peak generator Volts to how many pounds of force the spring is.