The First Spring 2020 Presentation and Updated CAD

On Wednesday (02/26), the Spartan Superway Wayside Power Team were doing the first presentation of the ME 195B. After the presentation finished, the mechanical team and the electrical team are continuing to develop their works. The electrical team were working on the problem that they had last week which were not able sent current to the motor. Apparently, they found at that it was the wire issue. For the mechanical team, we were continuing on our work with the CAD design on the current collector.

They are working to integrate the arm mechanism to the bogie design from the last year team. The figures above are our work in progress assembly of our current collector. We are still determining the best linear actuator that we are going to use. The above figures of the linear actuator are just a CAD that we pull up from the actual McMaster shelves.

Written By,
Reynaldo Jahja

Meeting with VTA and Continued Development of Shoe Mechanism

Wayside Power Team has continued to increase the work completed each week. In the most recent week the team was able to send Chuong, Ryan, Shane, and Alex to meet with VTA to learn about application and industry standards. The team was able to talk with Sr. Systems Design Engineer Alan Ng and Jr. Transportation Engineer Francisco Alolong, Jr.. Much of the meeting covered industry standards, application, technologies, and how the simple technologies were usually the easiest to maintain.

While some members met with VTA, the other members were able to spend some time working on the shoe mechanism. The team was able to produce a 3D print of the desired shoe clip shape with the recently acquired shoes. 

Unfortunately the shoe clip is not to the exact desired specification, so the team will have to revise the design to better fit some of the unforeseen problems in the current shoe clip design. A lot of design needs to be tested before completion as such the wayside power mechanism has much work before completion.

Written by:
Alex Ng

Development of Electrical and Mechanical Systems

On Thursday (02/06), Waylon and Melody discussed how to hook up a 24V power supply to a motor driver. They also discussed how to test the power transfer from the rails to the motor. Waylon looked for parts to buy for a voltage converter. Shane and Reynaldo went over designs, drawings, and parts. They redrew the existing platform to represent the actual track. They discussed possible designs for the conductor shoe mechanisms. Reynaldo modeled the track, adding insulators and aluminum rails. Shane assisted Reynaldo in specs of the drawings and looked up current sensors from Pololu that may be useful in the project to gather electrical current data.

On Sunday the team met and discussed what needs to be purchased for the electrical system. Two linear actuators, hall effect sensors, strain gauges, and voltage sensors need to be ordered. For the measuring system, the team will be using a Hall Effect Current Sensor ACS758 (50B Version) and LCD display. Melody and Waylon used draw.io to make the electrical schematic below (Figure 1).

Figure 1. Electrical Schematic

The mechanical team discussed the shoe arm mechanism. A single pivot point connection to the linear actuator will be used. The linear actuator stroke length will be 2”-6”. There will be one strain gauge on the center sliding shoe contact. The necessary force for the spring will be calculated. It was estimated that 6 PSI is required for the shoe. Next up the team will be assembling the steel cap and ramps.

Written by,
Melody (A. Bake)

Enhancing our designs

We are continuing to improve our electrical test station, track design, and actuator design. The electrical test station required some new wires and terminals to reach the power supply. We are using a power supply that can output more than 20V to account for voltage drop through the rail. The test shoe wooden bar was given another wooden block that provides a snug fit on the test rails. Shane found some aluminum in the engineering yard at school. We will be able to use this aluminum for the large portion of the track. Steel can be capped onto the aluminum to improve wear resistance. However, our order of conductor shoes were lost in delivery. We will have to hunt down those shoes for now. The shoe container material has not been determined yet, but it must be flexible and an insulator. Design of the linear actuators includes how to attach them onto the bogie. We are in the process of CADing the attachment and deciding on its material. The linear actuators do not need to be large, we are thinking about 2-6 inches, but they have to be strong enough to hold the forces we want and be able to compensate for changes in the track.

Electrical Test Station

Aluminum bar resting on Insulator (missing brackets under insulator and the middle layer is wood which is acting as a placeholder)