Design is an Iterative Process

[Chris Fultz]

Hi Everyone,
I've got a challenge for all those mentors out there interested in a design process...

Above is the first part of a post from JVN encouraging teams to document their design proces steps for 2011. We will be documenting our process steps as we progress through the season. Thanks to John for posting and encouraging all of us to do this.

I am actually going to start the documentation here. As JVN and others have stated, “design is an iterative process”. For Cyber Blue, our design process for the 2011 FRC season started last April, in Atlanta (in reality, the process never really ends or starts).

Listed below are some of the highlights of our design process to get us to January 8, 2011, for the FRC Kick-Off event. In many process flow charts, these would be classified as "review / reflect" activities.

Evaluate the Competition –
At 2010 competitions, especially the CHP event, we looked at other robots, and looked closely. We asked questions. Students were encouraged to look at five other robots and see how other teams accomplished the game challenge. We looked at drives, kickers, hangers, chassis systems, etc. We wanted to know who did what we did, what ideas worked well, what ideas didn’t work well, and what were some of the designs that we never considered. We documented these details.

Season Review –
In May, before we “lost” our Senior class, we held a season review. We discussed what we did well and where we need to improve. We talked about what to keep doing, what to stop doing, and what we didn’t do that we should have done. This discussion was focused on the robot and the design and strategy we incorporated, but we also addressed other areas of the operation of the team. We talked about our decisions and if we would make different ones after seeing how the game played out.

This "look back" right at the end of the season is important. Details are still fresh. You need to be open and candid and identify where improvement is needed. Don’t attack others, but try to be honest.

This review is a good time to identify areas where the team may need to focus or some skills that need to be developed (CAD skills, welding, wiring, etc.).

Fall Projects –
This year we completed 4 fall projects to help us be more effective in 2011. Only two were directly robot related, and the others are team functionality focused.

1. We completed a test program to compare the pushing / pulling power of 4”, 6” and 8” wheels, in 1” and 2” widths. The intent was to give us (and other FRC teams) some data to support the decisions on which size of wheel to use. This testing is done. We are still analyzing the data and will publish the results when we have some conclusions. As sometimes happens in testing programs, the results are really different from what we expected and we are trying to understand what we have seen.

2. We wrote assembly instructions for one of the 221 Robotic Systems chassis systems. This was beneficial to 221 Robotic Systems and also to us. We learned about this chassis system, students wrote the instructions and then learned while others tried to use them to build the chassis. Many new students got hands-on experience with tools, parts and instructions.

3. We built part of a field. We were able to clear enough space in our lab area to build about 1/3 of a field. We have a driver’s station and side walls and carpet. Once the game is announced, we will know what “field elements” are needed. Having this partial field will help us with one of the big steps in the design process – prototyping.

4. We cleaned out our store-room. We got rid of a lot of excess materials. We have nuts and bolts and bearings and other items organized and in labeled containers. This will save us time during the build season by making it easier to find parts, and to know quickly if we need to go buy something. (An added bonus – we made almost $170 by recycling aluminum and steel materials that were no longer needed. )

Mock Kick-Off
We complete a mock kick-off event for our new members and invite other new teams or new members from our surrounding schools. We use an old FRC game and show the animation and use the rules that are archived on the FIRST website. This activity prepares new students for what will happen on January 8 and helps them be more prepared and be able to quickly contribute to the team discussions as we begin week 1.


All of the activities above get the team members working together and familiar with each other. This can help with communication once the build season begins.

As you document your design process and design steps, consider including activities after the 2011 "season" ends and before the 2012 "season" begins to help you be more prepared for January 2012.

[czeke]

Chris, Team 1091, will also, do a day-to-day log, of their analysis and activities, which we will happily share, here on CD. We feel that openly sharing, of all ideas, is a major part of gracious professionalism.

[Aren_Hill]

Originally Posted by Chris Fultz

1. We completed a test program to compare the pushing / pulling power of 4”, 6” and 8” wheels, in 1” and 2” widths. The intent was to give us (and other FRC teams) some data to support the decisions on which size of wheel to use. This testing is done. We are still analyzing the data and will publish the results when we have some conclusions. As sometimes happens in testing programs, the results are really different from what we expected and we are trying to understand what we have seen.

I am really curious to see this paper, we're currently in process on comparing a variety of wheels for static friction levels, all 3" due to what we had on hand,
gum rubber roughtop
nitrile roughtop
SBR roughtop
Colsons
Colsons with a tread pattern applied
all similar size 3" diameter around 7/8ths wide

It'd be nice to have some more data to look at, I like data

[Chris is me]

The wheel width data could settle the endless debate on traction versus surface area once and for all. It would be very interesting to hear the results on traction in addition to tread wear.

[Gregor]

Were these results ever posted anywhere?

[Chris Fultz]

Originally Posted by Gregor

Were these results ever posted anywhere?

No they were not. We never made any logical conclusions from the information and we did not post it. The plan is to repeat some of the testing and re-evaluate. Due to some mentor changes and other projects that came up, we were not able to repeat any of the work during 2012.

[cadandcookies]

I will be very excited to see the results! My team has also been considering doing some research on different wheel types during the offseason. It would be interesting to compare results, provided both studies happen, and are similar enough to be directly comparable.