This week, the test frame design was finalized and we are building it. In addition, we are finishing the welds on the suspension, making sure all parts fit well. At this point, the suspension is almost completely finished. Also, we ran some preliminary tests on the test frame which confirmed that our actuator works perfectly with the frame. Once the test frame is done, we will run more complete tests with the suspension. Our work is on schedule to be completed by Tuesday, May 8.
During Week 8, we applied changes to the design of the suspension.
In our original design, there was swinging due to linear acceleration and a lack of vibration damping on the vertical axis.
Figure 1. Original design
Our suspension design therefore needed to be modified to fit the design requirements. The addition of a linear actuator across the links allows for control of the links and a spring-damper system will damp the vibrations. The linear actuator will move in response to the position of the links and the acceleration of the pod car. The spring stiffness and damping coefficient will need to be calculated in the future to build the spring-damper system.
Figure 2. Prime design concept
FEA was also done on a CAD model of our system. Our results indicate that deflection is not a major problem and the minimum factor of safety is good for our purposes.
Figure 3. FEA on spring-damper support
In Week 9, we will refine our design even further and begin assembling a bill of materials.
This week was spent preparing the final slides for Presentation 2, and actually presenting of course. This was the first presentation day in which every team participated. In addition, we had guests from London attending our presentation. We wish every team good luck as we all enter the final phase of the Spartan Superway project. Next week, we will continue our work at the machine shop. Below is our presentation.