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FEB 13: Visitor

FEB 13: Visitor

Today, Gene visited us. He has vast experience in the railway transportation and presented his ideas on how the Spartan Superway can excel at becoming the new mode of transportation. Gene talked to the small-scale team and shared some of his thoughts. Some of his input seemed too advanced or too extravagant to include into this years project with the remaining time left. However, his idea on track system seemed plausible. He did not have much to say on the current state of the bogie.

The chassis design is going a few changes to fit the new motor set up. By using direct drive for the bogie the chassis frame will be widened to allow adequate space for the drive components.

FEB. 6th: Motor Arrived

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FEB. 6th: Motor Arrived

The controls team bought a gimbal motor and are currently spending time on researching how it can run. Upon receiving the motor, the size was similar to the CAD drawings luckily. There was on aspect that wasn't predicted, however, which was that there is a metal shaft that holds the rotor to the stater. A new design was created to reduce the overall profile of the drive train as shown below. I will aim towards developing the chassis to mount the motor and continue to progress towards producing a prototype.

Jan. 30th: First Day Back

JAN 30th: First Day Back

Today we were introduced to the new building for this semester. Luckily the bogie components were stored together securely and most of the components were able to be found and located to the new small scale area.

Organization and cleaning up took up class time but the move towards producing prototypes is in need.

Week 15: Presentation

DECEMBER 5th: SMALL SCALE BOGIE IMPROVEMENT TEAM. The beginning of class period the remaining presentations were conducted including the small scale teams. A link for my presentation is available below. In my presentation it was addressed that a decision for moving forward with either differential or conical wheel design is needed to be made. To do so a comparison was made as shown below. 
Conical Wheels Pros: Used in the majority of bogies today. Easy to incorporate and produce. Reduces wear through passive ("natural") turning. Cheaper No need for independent axles
Cons: Hard to control. Does not account for inconsistencies in track. Making costs material and time.
Differential      Pros:      Off the shelf part.
     Precisely made.      Minimal assembly.  Not as dependent on track quality.      Cons: Price
Made for lego axles
Relatively hard to integrate. Gets benefits from tighter turning radius. Prevents natural turning motion.  Requires independent axles.
As shown the conical wheels have …

Week 14: Presentations

In class presentations were given to which none of the small scale was able to present due to time constraint.

From the Gantt Chart, this week marks the beginning of the FEA analysis for the bogie design. The main areas of concern will be the articulating joint and servo arm for track switching. Last years arm model was able to achieve a safety factor of 8.5 which should be similar to this years model as it is similar. However the linkage system will also have to go FEA to ensure that there is not failure at the joint where the parts are expected to have the least material. The articulating joint will go under similar analysis.

Week 12: Design

NOV 14th - Small Scale Bogie Improvements Team

Continuing from last weeks flanged wheel design, after increasing the angle to 25 degrees I was able to achieve passive turning. However, the dramatic increase of angle lead to excessive rocking back and fourth of the wheels. While not perfect the concept is proving feasible with more angles to be tested. Some concerns is that inconsistencies in the track may cause results to vary in some areas but with the small scale track team's efforts in improving the bending process the function of the wheels will most likely succeed. A comparison of pros and cons of using the wheels and differential is required for further development towards a final design.

I received information from professor Furman and his guest that bricklink.com has a wide selection of Lego parts that will aid in gear selection to ensure functional gear trains for using bevel gears with the differential. Additionally, the small scale track team and I visited Daniel Bolin …

Week 11: Small Scale Bogie

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NOV 7th - Small Scale Bogie Improvements Team

Within this week I tested the use of flanged conical wheels to assess the feasibility of using them for passive turning on the track. The initial design was referenced to an existing design that had a slight angle to the wheel of about 3 degrees. Two wheels were attached to an axle and by gravity was allowed to roll down a curved track. The wheels unfortunately did not move as desired and rather continued in a straight line. A new set of wheels will be tested with a greater angle. The updated design is shown below which has a 25 degree angle.

Updated Conical Wheels