Tuesday, October 25, 2016

Blog #8 10/26/2016

Hi,
This week our team was busy redesigning the brackets in accordance with what was asked of us after the individual group meeting with Furman and Eric. We also spent a deal of time working on the PowerPoint presentation, tabulating inventory , and drafting drawings to e-mail companies. We have started a Bill of Materials (Image 2) and should have that completed before November 15th (the deadline). We have yet to contact Vander Bend because we are fixing the rest of our track before we send them the improved curvatures. Despite not yet asking for a quote, we have reached out to them and obtained several contacts so we will keep in touch with them as soon as we are ready. We have e-mailed Kearny Foundry for a quote on how much it would cost to create a mold of our bracket (Image 1) and the cost of each filling of ALU 6061.

One of the problems we confronted this week included being unable to perform Finite Element Analysis (FEA) on an assembly and thus, we had to redraw the track as a single part. We simply redrew the loop to FEA (Image 3), where we accounted for the rest of the track with fixed points and proper weights. And below are several pictures of, but not all, the things we accomplished this week as we will be updating these into the overall Spartan Superway Folder for the others to access.




Track 4.1.JPG

Wednesday, October 19, 2016

Blog #7 10/12-10/18

Hi,
This week our team attended the seminar about the ME195 Report hosted by Dr. Agarwal. We also continued our improvements of the track which are shown below in Figure 1. Figure 2 shows how the U-bracket is connected to the support post. We quickly resolved our little problem with converting the metric system to english units. We attempted some finite element analysis (FEA) but it was limited to single pieces and the program could not do a finite element analysis of the entire assembly and so we will try again tomorrow with the full solidworks edition at the engineering building. We were able to do Finite element analysis on the U-bracket shown in Figure 3. Figure 3 shows the displacement of the bracket when a 5lbf acts on the part. The orange arrows shows where the force is applied. The green arrows simulate how it would be mounted. Reference back to Figure 2 for how it is mounted. As we can see, the left side goes under compression which would cause the track to droop downwards and not keep the track uniform. This week we will finish the FEA, presentation PowerPoint, update Gantt Chart, and start working on our bill of materials.

Figure 1: Full track assembly


Figure 2: U-Bracket mounted to Support Post



Figure 3: FEA on U-bracket

Wednesday, October 12, 2016

Blog #6 10/5-10/11

In this past week, we presented our project to the class and instructors. Prior to the presentation there was a big push that all the teams show that they had completed around 50 hours of work since the start of the project. We realized we have not worked for that many hours however we believe we are on track to complete our goals for the semester and the year. By this point we should have run finite-element analysis so we could get a jump on building the rapid prototype. We will be doing that in the coming days and spend the next week pushing to get some parts manufactured using the materials and tools in the design center.

At the end of our presentation, Professor Furman asked us some questions that we were prepared to answer, but we would like to provide more details about our plans. One of the things he mentioned was that the screws that hold up the brackets are problematic. This is very true, the screws are very tiny and are either stripping or bending. Ideally we would like to actually weld the brackets to the rail where we can without making assembly/disassembly more complicated. The brackets on each part (A-F) would be welded using the TIG welder, and where each part mates together, would be bolted together. Any remaining brackets and connections would have to use all new bolts and screws.


Another issue Furman had mentioned is that bending sections A-D could be difficult to do according to our design (2 straight sections with a bend in the middle). This was something that came up several weeks ago as we discussed our designs with the fabrication team. Ultimately, both of us decided to make a serious attempt at manufacturing the parts the more difficult way because it should make assembly the track more precise. We have a few ideas on how it can be manufactured but are aware that we may have to refer back to the previous design method.

Wednesday, October 5, 2016

Blog #5 10/5/2016

Hi,
At the beginning of our class we met with the other 12th scale groups to discuss any changes and expectations. Upon agreement, it appears that none of the work we are doing so far will collide with each other at the moment. This week, we continued working on our presentation because we wanted to accurately represent the amount of work we have done. We updated our Gantt chart because we needed to actually finish designing a bit sooner than expected. Our team has been gradually outputting more designs each week as displayed below. This coming week, we will be presenting and the plan is to finish designing, completing calculations, and running FEA for the designs by the 19th of October.



Figure 1. Update on bracket.  This should keep the track width uniform.

Figure 2: Overall dimension of bracket.



Figure 3: Two Loop Track