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The SRS helps sponsor a FIRST Team

Kevin Ross, kevinro@nwlink.com

robot.jpg (12063 bytes) Rainmaker One

Rainier Roboteers FIRST Team #360

Seattle Robotics Society

University of Washington

Bellarmine Prep

30"Wx36"Lx28"H  Weight: 120 pounds

NASA Ames San Jose Regional Team #360 finished 3rd out of 45 robots

Honored for the 'Best Offensive Round'

Disney EPCOT National Contest Team #360 finished 27th out of 275 robots.

Introduction:

I have to be honest: I am having a difficult time writing this article. There is so much I want to say, so much personal excitement for this project, so much learned from this experience, I find this article a little daunting to even organize! I thought I was going to be able to write this last month, but had a real problem getting past my initial writers block. I am going to do my best to organize my thoughts into something you can read. It isn't easy, but I think it is important to get the word out about FIRST. This was one of the most thrilling experiences of my life.

Let me backup and take a running start at it. Several years ago, I decided to change my life's goals. I have been quite successful financially, so I decided to focus my efforts on three main areas: 1) Getting physically healthy 2) Building a new house 3) Change the world by doing something about the lack of qualified engineers coming out of public schools. Seemed like some good goals. The first two are in my direct control. I drastically underestimated the amount of effort on that third goal. It seemed like a great idea at first, but it turns out there is exactly one of me, and about 10 million kids. Hmmm....

I have been looking for the appropriate vehicle that would allow me to help share the excitement of engineering to young students. I have been going around to local area schools in an effort to expose kids of all ages to robotics and engineering. I usually do at least a dozen talks at elementary and high schools during the school year. Students appreciated the hour long talk, but I never really had the sense that I had accomplished much more than a show and tell. There is little that can be accomplished in a single hour presentation.

Two years ago, teacher John Currie from Mt. Tahoma high school asked for my help with a select group of students who wanted to build a small robot. John is an extremely dedicated teacher who spent many of his own weekends coming to SRS meetings, learning about the technologies we used, and asking some really great questions. I had a great time going down for a few days where the kids managed to build small photovore robots based on a BotBoard. The students had spent about 2 weeks learning to solder, modify servos, and when I arrived, we spent a few days getting these little robots rolling about on the floor. The sense of accomplishment was evident with the kids, and I really appreciated the opportunity to help. This was a lot of work for Mr Currie, who I respect greatly for his efforts to go the extra mile. Having the opportunity to spend more than a few hours is the key to this project. It was also a lot of work for him. What is needed was something that had more structure, a support team, and an interesting goal that the students could work towards.

This year, I helped participate with a high school/college based FIRST team. I am quite happy with the results. This FIRST experience is a well organized, long duration project that allowed my fellow engineers and I to work through some tough problems with a great group of students. This was just the ticket needed to expose students to a full design, build, debug, and test cycle. I am quite happy with the outcome from the FIRST experience, and believe strongly that it is a great program that every student in the world needs an opportunity to participate in.

What is FIRST? Read on....

Our FIRST Big Surprise

About a year ago, a student from Bellarmine Prep, which is a high school in Tacoma, Washington came to an SRS meeting with a request. The student, named Ashlee Snodgrass, wanted to get a high school team involved in the FIRST competition.

At the time, most of us at the meeting had never heard of FIRST, and were somewhat intrigued at the idea. Ashlee explained to us that FIRST involved students and engineering mentors working on a robot project to compete against other schools across the country. The competitions had been going on for several years on the east coast of the USA, but not much was happening here in the west. This seemed like a pretty good idea in theory, but there was quite a bit hesitation in our group about actually getting involved. It is one of those big unknowns and sounded like a huge time commitment. Everyone was interested in seeing what was going to happen, but nobody was really jumping in with both feet to get involved. 

Turns out that Ashlee is a sub-five foot force to be reckoned with! After she convinced her school that this was a good idea, she applied for a grant to help fund the project. The school was thinking this would be a great thing to do next year. Ashlee surprised everyone and managed to get a NASA grant to help fund the project for THIS year. Somewhere around mid December, she surprised all of us with a quick little announcement that the project had funding and we were supposed to fly to New Hampshire for the kickoff event in two weeks, and was eagerly looking for SRS volunteers to mentor the Bellarmine students.

Gulp!

SRS members Larry Barello, Ryan Wistort, and me (Kevin Ross) stepped forward to take on the challenge. In addition, we lucked out as the University of Washington Electrical Engineering Department organized a student team, giving us extra student help. Professor Alex Mamishev, who is relatively new to the UW engineering department, put out a notice to students looking for engineering experience. The turn out was tremendous. We also called on several other resources, one of the most important being Paul Roush, who is a Bellarmine alumni and a mechanical engineer for the Tally corporation (and now a member of the SRS!).

The FIRST Experience

The goal of the FIRST program is to introduce high school students to the wonders of Engineering. FIRST is an acronym for "For Inspiration and Recognition of Science and Technology". The goal is pretty straight forward: Give students the opportunity to be exposed to an engineering experience. By doing so, they will start to learn what engineering is all about, first hand. FIRST encourages teams to bring together students, teachers, and professional engineers. The engineers are there to provide guidance, act as team leaders, and to push the project along through thick and thin. This exposure and involvment by the students is the key to the success of the program.

All good engineering experiences involve the solving of some problem. The FIRST Robotics Competition involves building a robot that can perform a task under the direct control of some student drivers. There are design constraints, time limits, documentation requirements, lack of resources, lacks of time, and of course stiff competition. Just like a real world engineering experience!

The contest starts with the unveiling of the contest. On January 6th, 2000, Larry Barello and I took a (very long) flight back to Manchester, New Hampshire to attend the big kickoff event. At this event, scheduled for the 7th, 8th, and 9th, we learned about the many facets of the FIRST experience. We attended engineering oriented classes about the control systems, pnuematic systems, and other technical courses. We spent a great deal of time learning from the more experienced teams. As rookies, we were treated to a wealth of information freely shared by these other teams. There were 470 teams world wide this year.

The Game

On January 9th, the details of the actual contest were revealed. To be fair, the contest is a closely guarded secret. There are just a handful of people who know the contest details before this kickoff event. In a large convention hall, packed with over 1600 attending team representatives, the contest details are revealed by dropping a large curtain that surrounded the playing field. All across the country, teams were up and watching to see what the contest involved.

field.gif (14594 bytes)

Diagram taken from the FIRST Robotics Competition manual.
www.usfirst.org

When the contest was finally devulged, it turned out to be quite a bit bigger than I had imagined. The field itself was 24 feet wide and 48 feet long. As you can see from the picture above, there are 4 robots on the field at each time, forming 2 alliances. The two robots for each alliance are working together to attempt to win the match. Mid-field, there are two goals. One for each alliance. In the middle of the field is an 8' wide, 15' high ramp with a horizontal bar at 5' above the top of the ramp. The goal of this contest is to pickup playground balls and stuff them into the appropriate goal for your alliance. There are two colors of balls. A yellow ball is worth 1 point, a black ball is worth 5 points.

goals.gif (13397 bytes)

Diagram taken from the FIRST Robotics Competition manual.
www.usfirst.org

As you can see, the goal is fairly tall. The goal is actually 6 feet tall, about 8 feet wide, and about 2 feet across. In this section, you can see that the ramp makes a nice little problem that needs to be considered. One other great feature was a hanging bar.

hanging.gif (8897 bytes)

Diagram taken from the FIRST Robotics Competition manual.
www.usfirst.org

Between the two goal structures, and 5 feet above the ramp, is a horizontal bar that is capable of supporting robots. If your robot was entirely on the ramp at the end of the 2 minute round, then your robot scored an additional 5 points. If your robot is hanging from the horizontal bar, you score 10 points. This made getting on the ramp and hanging an extremely important feature. Your score is a combination of points in your alliances goal plus whatever bonus points are scored from being on or above the ramp.

The Robot Parts and Rules

I must admit, after the contest is over, I was shocked, amazed, and completely thrilled to see the different designs that showed up at the regional and national competitions. The innovation level demonstrated by these teams caught me way off gaurd.

Each team returned from the initial kickoff meeting with two large plastic boxes, weighing, in theory, 70 pounds each. After nearly having a heart attack trying to carry my box through the parking lot at the airport, I managed to get it back to Tacoma where my FIRST team, the Rainier Roboteers, tore through the contents to see what toys awaited.

crates.jpg (33490 bytes)

The national FIRST organization provided these parts to each team. At the kickoff, there were 470 sets of boxes. Each set of 2 boxes contained identical kits of parts. The kit contained 'hard to find' items, and items that were complex. Every team was allowed to build their robots from a fairly generous list of parts and materials, but most complex parts had to be in this box. The idea was to insure that everyone had access to the same supplies. FIRST provided all motors, for example. Teams could supply things like extruded aluminium, 1/4 steel plating, plywood, etc. You were NOT allowed to reach into any other sources of goodies and pull out some sort of complex device that nobody else had access to.

FIRST provided all of the electronics, including a really nice radio and computer based control system specifically designed for the contest. They provided batteries, motors, motor controllers, and a host of other interesting parts. We were also allowed to purchase up to $425 of materials from Small Parts, Inc who is a major sponsor of the FIRST competition.

Everything else must be made by the team from a short but generous list of allowed materials. If it wasn't on the list, then you were not allowed to use it. This kept the contest fair by allowing everyone access to the same basic materials.

There were also strict design constraints on the robot. Actually, there were 17 pages of design points and limitations that had to be adhered to. Most were safety related. If you are interested, check out http://www.usfirst.org/2000comp/Docs/ for a complete set of documentation for the 2000 contest. The rules and regulations are quite extensive and very well thought out.

The major restraints were size and weight. The robots had to start out fitting into a 30" wide by 36" long by 60" high box. The robot also had to weigh less than 130 pounds. These are big and heavy machines!

The Design Process

The Raineer Roboteers jumped right into action as soon as they knew what the contest was. Design meetings between the high school and college students yielded a number of outstanding designs. Working in subteams of 4-6, many competing designs were proposed and discussed. This was a very lively group of students who all did an extremely respectable job of working through the rules of the game, constraints on the robot, and came up with our final design. I was extremely impressed at the level of participation and the amount of food consumed!

designmeeting.jpg (24527 bytes)

Design meetings with the various sub-groups

After working through some potential designs, our team started to create some prototype subsystems to see how the scale of the design worked, and to determine if their designs looked like they would work. This took the better part of two weeks, but was a very worthwhile time for the students. We tried to insure that everyone had an opportunity to contribute something to the design process.

collectorprototype.jpg (22459 bytes)

An early collector prototype

prototype.jpg (33266 bytes)

The final, working, collector/basket prototype, complete with motors!

The Building Process

After we worked on the design process for a week or so, we started on the building of the robot. We only had 6 weeks to build, test, revise, and test again our robot design. For a project this large, that is a pretty short time period.

The first, and most important component to get finalized was the base for the robot. Through our discussions, we decided to go with a 6 wheel drive differential steering design. We used a hint from members of the Seattle Robotics Society and dropped the center wheel of the drive system by about 1/4". This allowed for a little bit of tilt so that during a turn, the robot wasn't dragging the outboard 4 wheels as badly. This worked extremely well for us.

base.jpg (31702 bytes)

Scott Campbell of the University of Washington worked on the base.

The University of Washington Electrical Engineering department provided us with Scott Campbell as our full time technician. Scott was new to the department, and in fact this was his first assignment. He worked hard over the next 6 weeks getting our robot ready to go and did quite a bit of the machining for the base.

working1.jpg (25181 bytes)

Larry Barello helps David with the pop rivet gun.

Larry and I felt it was important to have the students deeply involved in the construction of the robot. That made an interesting set of problems in itself. For most of them, this was their first experience building ANYTHING. We spent a fair amount of time teaching them everything such as how to use a philips screw driver, drilling holes, and riveting. We also had a problem of not enough lineal feet of robot.

working2.jpg (23619 bytes)

Space was often pretty tight!

The size of the robot really limited us to how many team members could work at one time. This caused a bit of a problem since we had over 20 active students who really wanted to work on the mechanics, but only space for 6!

working3.jpg (25344 bytes)

Testing our vertical lift mechanism

Our robot has a vertical lift mechanism to lift the playground balls up 6 feet where the basket can be dumped into the goal structure. To implement this, we used an extruded aluminium product from Bosch. Similar to the 80-20 concept, this material is mostly used to create manufacturing workstations. Paul Roush, who is an engineer from the Tally corporation, came up with this design. He uses this material at work. Here, we created a linear slide mechanism. The lift motor being tested is from a Fisher Price 'Barbie' car. Its one of those riding electric cars that young children use. The motors were standard in everyones kit.

collector.jpg (24939 bytes)

The ball collector

Working from the prototype, Ryan Wistort implemented the ball collector. It uses two rollers as pinch rollers to scoop up balls and spit them into the waiting basket.

inaction.jpg (21337 bytes)

In Action

Here you can see the collector has loaded balls into the basket. The basket was then raised up using the  linear slide/Barbie motor lift, and the robot is ready to dump the balls into our practice goal. The four major components are the collector, the lift, the basket, and the control system.

The FIRST Summary

This is probably the first of 5 articles I am going to write about FIRST. I hope this gave you at least a glimmer of insight into what we did over those 6 weeks from January 9th to Feb 21st. I have a lot more to say on this subject. I appreciate your making it to the bottom of this article, I know it was kind of long. Please check in again for the next issue.

In the next article, I will try to show you as much of our design as I can. Our robot did quite well in the contests, and I think we had a great design going. I will show you our drive train, control system, materials, and some of the unique solutions that the students came up with. Just as important, I will show you what didn't work very well, and what we plan to change for our next robot design.

In future articles, I will add more details about how our contest went, the technologies that we learned about, how you can help your local school compete in a FIRST competition, and how we should all strive to establish a Northwest Regional competition.

In the mean time, please check out our picture gallery and also have a look at some of the videos that Larry Barello took on his website, http://www.barello.net/FIRST2000.htm