Week 17: Details Required

Happy holidays!

The team is still waiting on details from the other small scale teams with regards to build requests and material information. Kevin is still out of town, but the main reason that building would have halted for the moment would be to allow time for the other teams to solidify their requirements. These requirements, such as material to be used and dimensions of parts requested, would guide the build process moving forward in any case. Without solid requirements to work towards, there would be no meaning in working towards creating new parts.

Week 16: Archive Update

Work this week focused on gathering and preparing materials to add them to the main project archive. This included things such as the presentations made throughout the semester, bill of materials for parts and services purchased thus far and to be required later, and Solidworks CAD models of parts made.

As mentioned in previous posts, Kevin will not be in town to work on the build for the majority of the winter break. As a side note, other teams are still working to solidify the details on what they would like the track fabrication team to make next semester. The break provides time for those teams to finalize their plans, and allows the build team (Kevin) to take some time off from working on the project.

There is expected to be ample time next semester to build what is required, as Kevin will have more time available to dedicate to the project as necessary.

Week 15: Winter Break, Finals Week

Regularly scheduled classes have ended and finals have begun. No work has been performed on the bender due to focus on finals and rearranging machines and tools in the garage. Additionally, uncertainties pertaining to requirements from other teams has the potential to greatly affect the work that the team would need to do, so the request for specifics and solid details has been made to the teams that require work from us. The winter break is a good time to allow those teams to solidify their plans and for materials to arrive before construction on the bender resumes. See Kevin's blog post of the week for more specific information.

The tank desk mentioned throughout the past few weeks has been acquired for 0$ from Craigslist, and currently sits underneath a pile of other things, as the garage is being rearranged. It is estimated that the desk has the requisite size, robustness, and weight to allow the bender to be mounted to it and used as-is. The final verdict on this will come at a later time, however.

Week 14: Final Presentation, Next Semester

Work this past week focused on the final report, third writing assignment, and revising the third and final presentation for the semester. A tank desk was acquired as a potential surface for mounting the bender upon, and will look to be tested early next year. For the remainder of this semester and this year, minimal effort will be put towards the build of the bender itself. This is due to the requisite capability required of the team (bending of flat stock to specifications) having been met, and the potential of a change in the material to be used for the track a real possibility. The material tested on thus far has provided promising results, which will lead the way for what will need to be performed next. The current forecast is that any track the team will be required to build can be achieved in a timely manner in the coming semester.

Third presentation:

Week 13: Documentation & Reports

Work this week focused on completion of the third presentation and the final report for the semester. The presentation includes information for what has been done so far and what remains to be done next semester. The final report will provide an overview of what has been learned through work done this semester and what will be done next semester for our portion of the project. It will also include more specific detail about what the Spartan Superway project is, how automated transportation networks (ATNs) can have large beneficial impacts on cities and public transportation, with a focus on San Jose and the Bay Area. The final report will also include more specific details about what has been built for the project, with special mentions going out to people, groups, or companies that have had an outstanding or extraordinary impact on what we have done.

The creation of dies according to calculated values and the corresponding outputs according to specifications meant that we could have confidence in the work we have done thus far, and that we are proceeding in the correct direction for what is required of us. Being the track fabrication team, we expect that other teams will eventually have work they will ask of us, so we are aiming to have extra time set aside next semester to accommodate the yet unknown work that may be expected of us.

Week 12: Where We're At, What's Working

The first die created to produce bends exactly worked exceptionally well. Careful manufacture of the die and all other parts concerned meant that the end result was as expected, with close build tolerances lending themselves to the perfect outcome that was achieved. The next step is to create a die for the larger material and corner bend, and confirm that the numbers work for that as well.

Information from the track improvement team last week pointed towards potentially not needing to fabricate station pieces, so further details will be gathered towards that end as things progress.

Other teams have requested manufacturing services of us, mainly in the form of bending material or drilling through-holes. Additional details were requested from said teams, but no information has come back yet.

The new die, new bend block, and bent material are

shown above. The radius was as expected, and the arc

angle was also as expected.

Week 11: Setback And Solution, Bender Test Results

Work done this past weekend on the bender showed generally positive progress. However, with the radii of the dies calculated to be much smaller than originally thought, shear stresses and resulting moments applied to the bolt holding the wheel increased far beyond expectations. This resulted in both bolts planned for use being deformed due to the force applied, so a quick fix with 3/4" aluminum bar stock and spare 2" aluminum bar stock served as a useful roller. The most prominent outstanding issues that remain are ensuring that 90* bends are repeatable and to glean additional information about the station section of the track, so the remaining details are being gathered from the track improvement team towards those ends.

While the bender is being manufactured, thoughts about having a adjustable die is being put in. After researches, expandable die requires high precision and design which is going to take another semester. The most suitable solution is to have a quick die-switching mechanism that allow us or the future users to switch dies quickly for testing and manufacturing. This also means that position of the caster on the arm has to be adjustable.

Further build details and images are available on Kevin's week 11 post.

Bent screw due to shear force on the roller.

Table legs, to be used for Spartan Superway workbench.

Week 10: Outlook For The Semester, Progress

The details on the Gantt chart are to be revised in light of progress made on the bender and die thus far. Forming metal around a sample die by hand has produced promising results, so work will focus on making use of the current bender in combination with specific dies.  With the current progress, it appears that minimal additional materials will be required to complete the working bender. It remains to be determined if the precision necessary can be achieved with our bender, but results from this coming weekend should aid in decisions for the track improvement team and work being done in-house or contracted out.

From previous week's measurement, inner radius of 20" is confirmed and 1:1 scaled of wanted curve drawing is printed out. It will be used to precise the die radius by comparing each bend to the plot.

Below is an example of some work done this past weekend:

The current die being worked on with the holding block.

Work to be done on arm with roller (not shown).

Aluminum block to hold material (see above).

Hole has been drilled, and to be reamed out.

Week 9: Back To The Drawing Board?

Work over the weekend showed that the 1:1 die for the bender did not work, matching the results of the calculations shown in last week's presentation. Using the calculated die radius of approximately 10.4" for a 20" bend for our material will be attempted this coming weekend. If the bends cannot be created as intended, other analyses will have to be made to determine the necessary path forward.

The corners of the track from previous year was measured and had an average of 20.63" radius. The radii was considered consistent except one of the aluminum had a reading of 22.6" which is higher than 10% error. This error is big enough to have the bogie get stuck of fall off the track. The data showed that previous team probably did the bending by hand and did not have a consistent bending machine that serve their purpose.

data:

Each curve was measured 3 times at different locations and averaged.

Week 8: Second Presentation, Progress

The second set of presentations began this week, with the 1/12 scale teams presenting their new information from the past two weeks that was not already presented in the first round of presentations.

The work on our bender is going well, matching with the Gantt chart schedule as expected. Testing of actual bending of material is expected to take time, in conjunction with trial-and-error shaping of dies to achieve the bends required by the track improvement team.

Week 7: Gathering numbers

This week we focused on gathering information and numbers from previous year's design and compared with the actual product they produced. The main point of doing this was to see what challenges they met and why the track did not work properly.

The design for the rapid prototype has been reverted to the original design shown in the first presentation, contrary to what was verbally stated during the presentation. This choice was made due to material availability as well as available support options. 

Measurements:

Materials:

Week 6 - Finalize Initial Design & Models

Initial design nears completion. The idea for the original bender appeared to be more work than creating a copy of a Hossfeld, so a change in direction was made. Additional time required to accommodate the design is acceptable, as the plan between this week and the next is to finalize a design to begin construction of.

Access to the on-campus machine shop is yet forthcoming. Investigation into why the process is taking as long as it is will be made this week, as fabrication is to start soon.

Die sizing will be determined by the final numbers from the track team. A 1:1 die will not be used, due to the curvature required being fairly large. Odds are that revisions to die size will be the most time-consuming portion of the project, if bender arms can be fabricated without much difficulty.

See individual blogs' weekly post for more information.




Presentation 1:

Week 5 - Presentation 1, Impacts On Prototyping

The first round of presentations continues this week. Plans for our bender are currently in flux, with requirements necessitated by other teams not yet fully defined. The most significant dimensional requirements stem from the track improvement team, which detail the requirements of the new track. 

Intercommunication continues with all other small-scale teams, as weekly meetings and the Slack group aid in information sharing. 

An updated Gantt chart outlines the goals we aim to achieve and the timeline in which we plan to do so, but the impact of delayed access to the on-campus fabrication shop and special requirements by other teams have yet to be accounted for. However, we believe that there is still ample time to complete a prototype on time, and that we are still on track even with a slightly compressed schedule.

Week 4 - Fab Lab Access, Presentation 1

Only a few updates this week:

The process for gaining access to the fabrication lab on campus has been slow, so we intend to perform fabrication with our tools at home if access to the lab requires more time than we can afford to or plan to wait for.

The team is presenting on current design work and progress today. To manipulate a small number of pieces, especially where adjustments may be necessary, we have found that manual benders are a good starting point. Current plans are to build something similar to a Hossfeld^TM bender, the main point being the utilization of a die to form the track around.

Week 3 - Research and Background

Currently, effort is being put towards researching means of material manipulation, specifically for bending our bar stock. Basic research so far shows low-cost methods are all manual, utilizing either torque/leverage by hand or applying pressure via hydraulic ram with a die.

Effort is also being put towards gaining access to on-campus machine shops. Seeing as iteration and design are our focus for the coming weeks, this is not yet an issue. We have some time to get things worked out on this front before it becomes an issue. Kevin has some tools at home, so work may proceed there if necessary.

With regards to last week's post, there are several updates that can be made:
1) One loop of the track is currently usable, and restoration of the track takes precedence over fabricating a new one at this time. Some material is available from last year to expand, if possible.
2) Some fabrication tools are non-operational. See images below.
3) Communication with other teams has been set up, namely in the form of Slack and Google Drive.

 Issues:
The band saw shaft broke, so the entire bottom assembly with the motor has been removed.

 

The grind disc on the grinder is down to bare metal. Would have to look to replace it to use it.

The mill is missing the drive mechanism to allow for vertical movement of the head.

 

The lathe appears to be alright, but it is dusty and there's no oil nearby to use to lubricate it. Did not turn it on to run it for fear of running with no oil in the gears.

       

      

Updated gantt chart: 

Week 2 - What's Now, What's Next

The current goals laid out for us on the Small Scale Track Fabrication team are:

1) to create a method or means by which aluminum bar stock can be reliably bent to shape, and

2) to develop a means to measure track length,

with the goal to ensuring that everything has been or will be fabricated to the required dimensions.

A more immediate goal that could be pursued would be to return the track to the usable state it was in at the end of the spring semester, to aid the bogie team and track improvement in understanding the previous issues that had occurred. 

Another immediate item that could be pursued is to determine the usability of available fabrication tools. In the shop where the project is currently being housed, several tools do not appear to be in working order, so work with Eric Hagstrom and the professors must be done to determine fixes or workarounds for what or how we may need to fabricate.

Communication with past or current individuals or organizations that are or were involved in the project may be key in increasing visibility to the community or sponsorship for the team. No details about this point yet.

Investigation of the previous work that has led to the current track design is important to understanding how decisions were made. Calling upon the general archive or individuals that have worked on the project will be helpful towards this end.

Communication with all other teams will be crucial to ensuring that a cohesive final product is achieved. One issue that plagued the previous year's team was the inability to integrate all systems well.

Common build materials for the track, such as aluminum bar stock and machined metal, appear to be in good supply. No action appears to be needed on this front at this time.

Research shall be done to look into past or current designs of similar real-world systems for inspiration and insight, which will also highlight benefits and detractors of using such a system. This is currently beyond the scope of our model design, but will aid in decision-making in the future, especially if there is intent to directly scale the model to full-size.

We will look to add pictures within the coming days to highlight several outstanding issues mentioned here.

Week 1 - Team information and objectives

Shengsong Cho

Kevin Yoshihara

Skills:

Experience with machine shop tools (lathe, drill press, mill, band saw, etc)

Contact information:

Shengsong Cho

ryryco1234@hotmail.com

925-321-7817

Kevin Yoshihara

kevyoshi0@gmail.com

916-897-0376

Proposal:

Design necessary processes and methods of fabrication to create small scale track for the Spartan Superway project. Additionally, fabricate the track in-house as time and availability permits.

Sketches:

Gantt chart:

Budget: $2000