Monday, March 13, 2017

Week 6

Procurement:
Hardware for the mate the ribs and clamps on to the rack were purchased. The match die and drill bit were sourced from home. Bolts for to mate the solar racks were also purchased. The hinges for the acrylic box were purchased. The next step for fabrication is cut the aluminum stock down to size for the sides of the rack along with the supporting joints. Once down to size, the aluminum stock will be drilled and tapped.

Fabrication:
Several more of the 6 cell batteries were downsized to 4 cells.

Testing:
The newly modified 4 cell batteries were tested over the weekend. Several discharge and recharge cycles were placed on the batteries. It was determined with approximated 60 watts and 1 amp output from the solar panels, a battery would be fully charged with 5.86 volts and 2222 mAh energy capacity under a hour.



Monday, March 6, 2017

Week 5

It was decided to reduce the batteries from 6 cells to 4 cells in order to drop the voltage. This would allow the motors powering the bogie to be ran directly off the batteries without requiring a buck converter. Modifications were made to prototype a 4 cell battery from a 6 cell battery. This battery was tested to be capable of powering the Arduino, sensors, and motors. Before retrofitting more 4 cell batteries, I tested this prototype battery over the weekend to ensure charging components are compatible. The weather this weekend was terrible with random showers throughout both days. A brief window of direct sunlight allowed me to charge the battery to roughly 15 minutes.


Over the weekend, the connectors for the batteries and associated components arrived. Heat shrink wrap for additional battery modifications were purchased. I can begin making modifications to all the batteries and associated connections.

The manufacturing team created a prototype of the overlaying rib. This design of the rib will allow the rib to bolted down along with a clamp instead of needing to weld. The fitment of the rib was tested with the solar panel clamped onto the rib. The edge of the solar panel needs to rest on the rib without any overlap passed the bend of the rib.


Wednesday, March 1, 2017

Week 4

Solar Racking Design:
New changes were made after last week's discussion. The track team expressed doubts of welding. In order to alleviate any extra burden on welding the solar racks, the design was changed so that the ribs could be bolted into place. This new idea was explored with the manufacturing team as the ribs will be produced by Kevin.



A clamp created to sandwich the solar panel between the clamp and ribs. The clamp are adjustable and uses the same hardware to bolt down the ribs onto the rack. Rubber inserts will be placed between the clamp and solar panel to prevent damages while promoting clamping force.



There are still a few minor tweaks that will be needed implemented to finalize the Solidwork design. The design should be completed this week.

Procurement:
A new connector for the modified 4 cell batteries were decided with the Controls team. 11 sets of connectors were order for bogies, charging modules, and batteries. The new 4 cell batteries will need to be shrink wrapped. Proper sized shrink wrap will be purchased locally.