A Curious Mechanical Engineering Student

This week was a very busy week for the half scale team. Working together, Joey, Ryan and myself were able to manufacture through rapid prototyping a small test bed system for the tilting mechanism. We were also able to finalize a mock suspension system for the half scale bogie system on Solidworks. This utilized a chain driving mechanism as well as a strut system to act as an anti-roll mechanism. Although this is only on Solidworks, it can be implemented for future teams to use or even improve upon. We then finally got parts from the machinist and have started to partly re-assemble both bogies.

This week was mostly getting a CAD model together of the tilting and anti-roll mechanism. I also had a CAD of the brakes that would be used, but due to the lack of the ability to get brakes, a prototype model is to be created once we get access to bicycle brakes. After coming up with a solid idea for a tilting model, Joey was able to CAD a model of it. I then decided to work on the anti-roll mechanism, which involved finding a strut that would match the dimensions. A CAD model is still in progress and is to be completed by next week. I then looked at ideas to have a small test bed for tilting, and that involved 3D printing small miter gears and have a small test bed with a gyroscope to demonstrate the tilting mechanism. The CAD would represent what our system would look like if implemented on the half-scale system. The parts to fix the bogie are to stated to be finished by next week, depending on how fast the machinist works.

In this week, I worked with Joey on the half scale team getting a test rig to work. Our test rig was the basic overall mechatronics side of things. This included a stepper motor for the steering, and two DC motors for the propulsion. We also got some parts machined for the half scale bogie. Roger, the technician at the ENGR 123 machine shop helped machine some spacers and jackets for the steering shaft. The modified steering shaft and the modified gear were sent to the Central Shop, but the return time around 2+ weeks from the beginning of this week, so assembly of the bogie is going to take a significantly longer amount of time than expected.

This week we recieved our McMaster order for parts to fix the half-scale bogie. This included new sets of fasteners, rods for the steering shaft and for spacers, and other miscellaneous components. Since access to machines to make our components is very limited, we have to ask the shop technicians to get our parts made for us. A couple things we are now working on are getting the parts back to re-assemble the bogie and look into the braking and regenerative braking system.

In this intro week, my team and myself were thrust into the previous bogie design from the 2016 - 2017 year. After a brief introduction of what we are to work on, there were somethings that went wrong with the previous year's bogie that needed to be fixed, which includes the bent steering rod at the top of the priority list. Figure 1 Twisted Steering shaft Even though we have taken the majority of the bogie apart the steering shaft remains lodged in the bogie due to several defined constraints that can't be removed. Figure 2 Constrained gearbox The gearbox is held in by a welded plate and press fitted bearings which prevent the gearbox from moving about, but thus creates it extremely difficult to remove.

This blog is an introduction to myself and the work that I do.  My name is Nathan Srinivasan, which can sometimes be a mouthful. I am currently a sophomore at the wonderful San Jose State University obtaining my degree in Mechanical Engineering, where I will be able to use this experience and go out into the engineering field and create things that will affect the world in some way.