Posts

Final Presentation and Prototype Showcase

This week was our final presentation as well as the prototype showing. Our presentation went extremely well even though we unexpectedly had to present first. After the presentation, we watched the other teams' presentations. The full-scale teams were first, followed by half-scale, and then small-scale. The prototype drive bogie was finished on Friday, May 3rd, including the alterations that needed to be made to it by the Motor team. In addition to the presentation to Dr. Furman, the Bogie Integration Team was invited to the SJSU Mechanical Engineering Alumni Event on May 9th. We presented our project as well as introducing Superway to the Alumni and ME faculty. This presentation went very well and attracted a lot of interest. A link to our final report and my LinkedIn account can be found below: https://www.linkedin.com/in/mifsud-nikolas/

Final Production and Presentation Prep

Image
The last 2 weeks were spent assembling our drive bogie. Brandon and I spent a little over 40 hours between fitting, filing, boring, and welding the components through the weeks. Due to changing from metric to customary for assembly, there were some tolerance issues which required fixing with filing. The drive bogie turned out very well as shown below. The bogie is currently at Superway to have other teams integrate their systems. There was a slight issue with the alignment of the axle for the motor team. This was caused by shifting or warping of parts during welding and will be resolved by increasing the hole size by milling. Also, after speaking with guideway team, we have decided to shelve route selection for this year. Their third rail would not be ready in time and we would require having parts machined. In addition to preparing for the Senior Project presentations on May 10th, Dr Furman requested that the Bogie Integration attend the SJSU Mechanical Engineering Alumni Event. We

Steps Towards a Final Product

This week consisted mostly of finishing up other teams' presentations. This was due to cutting our time short to move the full and half scale tracks from campus to the new Superway location. Other than that, the water jet cutter was fortunately fixed this week and our sheet metal was cut. This means only cutting the tubing and welding the project together remains for our production. This puts our plans slightly behind schedule but should be entirely manageable.

Spring Presentation 2

This week, we gave our presentation 2 for the Spring semester. This presentation served mostly as an update to our design changes. We were intending to have started production of our parts by the time of the presentation. This did not happen do to a breakdown of the water jet cutter at Makers' Space. As of the time of writing, the water jet cutter will be repaired by 4/16/2019. This will allow us to cut our parts with only a slight delay to our original plans. The presentation is embedded below. Most of the changes made to the designs were either refining for maneuverability (resizing holes to inches rather than metric, for example). Other than these, there were some dimensions which had finally been provided to us from other teams to mount their systems to the bogies. As general updates, the motor team has found that their motors can move in reverse, meaning there will be more space on the slave bogie for other teams' components.

Manufacturing and a Slight Change to Superway

This week consisted mostly of playing the waiting game. Our designs are finished and now include the sizing of the last components we needed from other teams. Myself and my teammate, Brandon Tarter, will be going to SJSU Makers' Space on Tuesday April 9th to get trained and cleared to use the waterjet and make our parts. Hopefully, we will be able to make our cuts on the same day. It was recently discovered that the motors purchased by the Motor Team are unidirectional, meaning the current design for Maker Faire will not be able to operate and return to it's starting position autonomously. To rectify this, Motor Team, with our help, will be reinstalling the old motor to the slave bogie for reverse drive only. This complicates the project for everyone involved, but we feel this the least disruptive way to solve the issue.

Preparation for Full Assembly and Production

Image
Following our presentation, there were a few issues that needed to be addressed. The drawings needed small alterations based on the materials we will be using. Spacing was changed slightly due to the sheet metal being in customary units rather than the metric we designed for (0.25 in vs 3 mm). Another change was moving the lower passive wheels down slightly as to accommodate the change in track sizing. With these changes, the designs are ready for other teams to incorporate their parts into the bogey. The files have been available for the last few weeks but now the track CAD is complete as well and ready for assembly.

Last Minute Details and Modifications

Image
After producing our shop drawings for the sheet metal components of the drive bogie, we were notified by the motor team that there was a clearance issue with the new track width. The in-hub motors would be overhanging by about 5 mm on each side. To rectify this, I have been planning out an adjustment to our CAD models to remove 10-12 mm of width on the drive bogie. Due to this being only a slight adjustment that doesn't affect all of our components, we are still moving forward on sourcing materials and preparing for production. We will be utilizing the central shop of the engineering department as well as the Makers' Space for fabrication. Below is one of the shop drawing that remains unchanged by our adjustments: