Drawer Slide Mechanism

Dr. Furman recommended a mounting solution for the charging component board that would be hidden but also easily accessible to users to swap batteries. A mechanism similar to a drawer was suggested. Research into drawer slides for cabinets were done. There are three main types of drawer slides that are available off the shelf; epoxy-coated, ball-bearing, and bottom-mounted drawer slides.

Each type of drawer slide has its pros and cons. Epoxy-coated and ball-bearing type slides both are designed to be attached to the sides of a drawer. Epoxy-coated slides uses two plastic wheels at each end to allow linear motion of the slider. Ball-bearing slides are also mounted to the sides of a drawer. Ball bearings are utilized for motion and offer lower friction compared to roller bearings used in the plastic wheels of the epoxy coated slider. Bottom mounted slides are designed to be a single rail mounted underneath, while glides on each side prevents wobbling.

Ideally, the charging components board would be mounted underneath the solar panel for concealment. A bottom-mounted slider attached to the underside of charging components board would require two flat U-brackets to support the front and end of the slider, along with glides to prevent wobble. Epoxy-coated and ball-bearing sliders has to be attached to both sides of the charging components board. Supports on each side will have to be created to mount the other half of the epoxy-coated or ball-bearing sliders to the support frame.

The above scenarios will be created in SolidWorks to visually see the ideas and be able to analyze each possible solution.

This week, I began doing a rough calculation of the solar panel with using 1000W/m^2 of irradiance according to standard test conditions (STC) and the area of the solar panels. After further thought, these levels of energy produced are theoretical maximum which can only be reached under ideal conditions in a laboratory setting. More research led to using NASA's Surface Meteorology and Solar Energy Available Tables. The tables lists maximum radiation incident on an equator-pointed tilted surface per latitude and longitudinal input. The table also offers optimal angle per month of the year. For November and the location of the workshop, the optimal angle is 58 degrees southward. The average maximum radiation incident is 4.41kWh/m^2/day. Using this data, each of our solar panels can provide 373Wh/day of energy.

Testing Solar Panel

Last Friday, I brought home a set of the solar panels along with charging equipment. I began cleaning the equipment and making visual checks for damages. A rough outline of the circuit diagram was drawn on paper. I noticed that wire size seems be chosen randomly for various connections according to the battery box. I made a note to check NEMA standards for wire size according to amperage when measured. I ordered a multimeter to test amperage at various locations. Currently, I am working on incorporating quick disconnects and measurement points in the wiring schematic.

New Design Concept

For this week, we are exploring a new solar panel structure design that will incorporate pre-fabricated ribs from the manufacturing team. With this design we are hoping to reduce the time to fabricate ribs to support the solar panel. After finalizing this design, we will have to a failure analysis in order to compare with our previous design. After a choice is made, we should then work on the bill of material.

Presentation #2

Currently, I am stressing over our second presentation. I am going over the feedback from our first presentation and seeing key areas where we can improve. I feel that a little overlap cover areas missing in the last presentation would be advantageous to our presentation.

We began to look into sources to supply aluminum for the solar panel frame and rotation hinge. We also need to look into gaining shop access and figuring out what times and days we can meet up to work on prototyping and fabricating.

Furthermore, the sponsorship letter and list of potential sponsors are coming to together. We can begin to send out letters next week. 

This week we began testing the mechanical bogie loaded. I started to compile a list of components of the bogie.

A draft of the sponsorship letter was created. Further, search for companies and contacts to reach out to has began.