Week 15: Preparing Presentation #3

This week the first set of teams presented to us their sub-groups progress. We are preparing our final presentation in the meantime trying to figure out what force the linear actuator will experience when the boogies accelerate at our max assumed value. Also, new FEA in the linkage system reveals that the lowest safety factor is in the horizontal links shown below in figure 1 with a safety factor of 1.69.

Figure 1. Horizontal links and the stress with safety factor of 1.69

Week 13: Evaluating our new prototype

Our new prototype on Solidworks requires us to perform new FEA and to find the force that the linear actuator will have to exert on the worst case scenario. However, our team suggested we research more into the active components needed to make this approach work first. I needed to do personal research to report back for a discussion with my group members on how to power and control the linear actuator. I found that as an option to control the linear actuator we will need a gyroscope, Arduino, motor driver, and a battery with a battery charger and possible an accelerometer. Fortunately, Dr. Furman had a motor driver that he can let us use for our project, which will allow us to operate the linear actuator from an external power source such as the battery.   

Week 12: New CAD Model

The new CAD model of the suspension unit makes the vertical distance reduce by 6 inches, which is good for practical applications of the suspension unit. I worked with Colin and Joshua in helping direct some of the decisions of the form and research for actual parts that we can buy from McMaster website so that the construction on CAD can be realistic when it comes to building the physical prototype. Below is the new CAD model of our new design as seen in figure 1.

Figure1. Vertical dampening unit is the center link like in the old design

The linear actuator is in place in a position where we are able to achieve a range of 19 degrees in inclination and 24 degrees in declination, which is acceptable for our target goal of at least a 17-degree range from the horizontal. 

Week 11: New iteration on the CAD Model

One of the comments that we received from our presentation number 2, is that the vertical length of the suspension unit might me too large. Which is because of the frame is on top of the vertical dampening unit when it does not have to be necessarily like this. My team and I realized that it is true as seen below in figure 1.

Figure 1. Frame on top of the Vertical Dampening unit

My group and I then went back to the drawing board to come up with a different form that will still encompass the same function. After, long thinking sessions, I came up with the idea to make the vertical dampening unit part of the center link in the frame. To do this, we would have to add some attachment points that could be welded on and make the frame double sided on each side of the vertical dampening unit. This will essentially make the total vertical length of the suspension the length of the vertical dampening unit, which should reduce it by 6 inches. 

We will continue with this new design concept on CAD

 

Week 10: Presentation 2

This week we gave our presentation number 2 to the Spartan Superway Team on our progress. We showcased our rapid prototype and received feedback on our design. Dr. Furman recommended looking into air dashpots and with an electronic orifice. My group and I need to finalize our design so that we can begin further analysis. A link to our slides is below
Presentation 2

Week 9: Preparing of Presentation 2

This week we had the 1/12th presentations that updated us on their progress. After, I started on setting up the presentation template on google slides to get a start on our presentation. I also added the rubric within the comments of the slides so that we can hit all the points.

I got the group to use google hangouts so that we can communicate over the mic as we work on the slides online. This really helped speed up the collaboration and will be something we will start to use. Furthermore, we came to an agreement that an active approach to our design with our original frame design will be a good balance of functionality.

Week 8: Further Evaluation on Design

This week the group and I discussed how we might be able to reduce the pitch swinging due to the longitudinal acceleration. It was found from the previous calculation that 14.3 degrees of angular deflection to be of significance for passenger discomfort. The group and I had some trouble of figuring out possible solutions within the scope of a passive approach.

I brought up that the reason we are having a difficulty with coming up with a final design that would stop or reduce pitch swinging is because we have limited our designs to passive only. The group and I discussed that a complete revision of the design may be needed. As we were discussing, AJ and the summer half-scale team joined our discussion and mentioned that linear actuator can be used to control the pitch swinging.

So our group then focused our attention on using a linear actuator in the frame of our original design to have control. The linear actuator can be used statically (off) for longitudinal acceleration and used dynamically (on) in cohesion with the gravity effects to pitch-level the pod-car while traversing on the inclines.