Wednesday, October 17, 2018

Week 7

Week 7 Update 

This week, we decided to continue our design work for the curved section of the track. Our presentation will be next week, so we are trying to meet that deadline. We want to finish most of our design by then so that we can continue to move on to analysis and finalizing our design. For next semester, we want to focus on getting all manufacturing done, so having the design finalized soon is crucial to this. As of right now, we have the design of the third rail finished. We are going to be going with a triangular design as this would be more effective than having a diamond shape (figure 1). We are hoping to have some FEA done by the end of this week (10/19/18) in order to prove that our triangular third rail is our best choice. The purpose of the third rail is implemented in order to assist the bogie with turning. The supports shown in figure 1 are most likely going to be welded on. 

Figure 1: The design of the third rail we will be implementing into our design 

Moreover, our next move is to start designing the junction in order to run some analysis on that as well and add it to our design. Once we have the third rail, curved section and junction, we can start finalizing our design. Since we are already halfway through this semester, we want to start finalizing our designs in order to stay on track for next semester. The junction track is shown below in figure 2.

Figure 2: The design of the junction we have done so far  

Also, in figure 3 we show how the curved track plus the third rail should resemble. Again, we are still borrowing the Futran track specs and adapting them for our use. The curved section was the reason behind us switching our track design from the cross cross-section to the 8x8 cross section. Futran's original track was going to be too difficult to manufacture, especially the curved section so we decided to change the design. However, the rest of the track will remain very similar to Futran specs, as can be noted in figure 3 below.

Figure 3: Curved track plus the third rail concept design  

For next week, we are going to be focusing on analysis and getting our presentation finished. We want to be able to present new information, so analysis is very crucial for this. We will be working on familiarizing ourselves with ANSYS in order to proceed with analysis. 

Reminder: If we are able to get enough funding for our track, we are going to be making the junction portion of the track out of steel. The straight portion made out of wood that was left behind by previous teams will remain and be used. We are working to make these tracks (wooden and steel) compatible enough to have the bogie drive on it. We definitely want the third rail system to be made out of steel though, as the summer team did not have successful results with their wooden rail. 

Wednesday, October 10, 2018

Week 6

Week 6 Update

This week we decided to focus on designing the curved section along with the third rail. We wanted to design the third rail because we need to analyze it soon. We hope to have this completely done by the time presentation 2 is due. Below we have attached some designs we are considering for the third rail. In the designs that are solid, the supports for the rail will be welded on. If the designs are hollow, the supports will be bolted on. All arrows in images point to where the route-selection wheels make contact with the third rail. 

 Image 1 (left): This image shows a diamond-shaped cross section for the third rail. 
Image 2 (right): This shows a diamond-shaped cross section that is hollow (made of sheet metal). The supports would be bolted on. 
Image 3 (above): Shown is the triangular cross section made of sheet metal
 Image 4 (above): Show is the overall look of the bent railing. The solid diamond-shaped cross section is displayed
Image 5 (above): Image shows a solid triangular-shaped cross section for the railing

The curving track portion plus the third railing is still being designed, but we will most likely have it done by the end of this week (10/12/18). 

We are also getting a lot of questions from other teams and would like to re-address them on here:
  • Can we make the gap more than 4.8 inches?
    • No, we are trying to keep the bogie as stable as possible. Also, the wooden track dimensions are NOT Futran dimensions, and for the steel portion we plan to use Futran dimensions because the bogie is designed accordingly to that. 
  • How will the wooden section and steel section (junction/ match up?
    • The wooden section has different dimensions than the steel, but that should not be too much of a problem. As of now, we are going to use the beams made of sheet metal as shown in image 6 below. This cross section is 8x8 inches and we are planning to add whatever is necessary to the wooden track to match this cross section. The wooden track is made up of construction lumber with cross sections of 1.5x7 and 1.5x5.5. Also, the steel portion will be taller because it will include the third rail, but that should not be a problem with the wooden part because it does not need the third rail added. 
 Image 6 (left): The cross section we are planning to implement on the beam 
  • Will the bogie be able to clamp onto the track?
    • Yes! We are currently designing for this to be possible by changing the track. The cross-section that was provided by Futran is shown in image 7 below. This cross section is problematic because it will cost too much to manufacture, so we are using the cross-section shown in image 6 above.  Image 8 below shows that the 8" x 2" rectangular steel tubing we are planning to use for the new cross-section design is capable of being curved to suit our junction and curved track sections.
 Image 7 (left): The cross-section of the beam, taken from Futran's design

 Image 8: 8" x 2" steel rectangular tubing bent to an outside radius of 58' 4" by Longero.

Wednesday, October 3, 2018

Week 5

Week 5 Update

For this week, we decided to focus on dimensions and design of the third rail system. 
For our dimensions, we are currently going with what Futran was able to provide us. Below is a table with the different dimensions  and figure 1 shows where those dimensions are placed. 

Table of Dimensions

Dimension #Millimeters (mm)Inches (in)Notes
152020.47Space between the outside supports
21224.8Dimension of the gap
32007.87Dimensions of the top and bottom of the cross beams that support the wheel
42258.86Dimensions of sides of the cross beams that support the wheel (plus the thickness of the sheet metal)
52208.66Dimensions of sides of the cross beams that support the wheel (minus the thickness of the sheet metal)
656622.28The height between the cross beam and top of guideway (plus sheet metal thickness)
756322.17The height between the cross beam and top of guideway (minus sheet metal thickness)

**All dimensions from Futran

Figure 1 (above): Where we were able to pull the dimensions from 

We are going to be sharing these dimensions with the other Full-Scale teams in order to have them design their portions accordingly. These dimensions are more than likely the dimensions we will be using for our final design in order to keep everything concise and not change things at the last minute. 

We are also working on the third-rail design. We received an e-mail from Ethan that shows a different concept for the third-rail; this is shown in figure 2. However, after taking it into consideration, we are more than likely not going to be using this because it seems to pertain to sharper turns and not continuous turns. We will continue our design using a beam angled at 45 degrees to help support the bogie during a continuous turn.
Figure 2: Alternative design of third rail.

We are also looking into manufacturing and how much that is going to cost. Currently, we are finding that the cross beams themselves are very expensive to manufacture in steel. We do not want to manufacture a solid beam because that is the most expensive option, so we decided to break the beam into three different cross sections. Figure 3 shows what these cross sections would look like. 

Figure 3: Possible alternative track cross section.

For the next week, we will be furthering our design in order to start some analysis. We are currently on schedule for presentation #2. We are hoping to add more designs to that presentation as well as some ANSYS analysis.