We used the tools discussed in Part 1 – Game Theory to determine our strategy in Part 2 – Strategy and Research which allowed us to defined our Robot Requirements in Part 3 – Robot Requirements for this season’s game (and game manual). Now we are ready to build a robot.
To keep this conceptual Robot in Three Days as approachable as possible, we are going to start with the AM14U4, KoP Chassis (am-14u4) from AndyMark. We will build our kit in the 28.3″ wide and 28.3″ square configuration.
Next we will setup our drive to be able to handle the HAB mid height. We will optimize our robot with the simple AM14U4 Upgrade Kit 8in. SD Pneumatic Wheels from AndyMark. This will allow us to drive on and off of the mid level of the HAB.
Next we will build a simple HATCH collection system. Since the LOADING STATION and CARGO BAY are at the same height, all we need to do is build a static mechanism to collect the HATCH at the LOADING STATION then release it at the CARGO BAY.
We will build a simple pillar in the middle of our robot that is 1’7″ off of the ground. At the top, we will put a a circle that is slightly smaller than the center of the HATCH (a 6″ circle) with four small spring loaded slats, like the spindle of a compact disc player (image below).
Next we need to be able to remove the HATCH from the spindle. On both sides of the spindle, we will mount a pneumatic cylinder with a short stroke to push the HATCH off of the spindle and press it to the CARGO BAY, securing the velcro and in turn the HATCH.
Another way to brainstorm mechanisms is to look at existing technologies. Our favorite way to do this is to look at industry through one of the best shows ever: How It’s Made! Below are a few videos on how disc-like objects are made:
Next because the CARGO will fall out of the LOADING STATION at 3’1″ and the bottom of the CARGO BAY opening is 2’7″ with the top at 4′ we can collect and deposit CARGO from the same location on our robot. We will add a basket, approximately the size of the ball, at 3″ from the ground on our robot. The box will have an open top and sloped front, will be mounted on a hinge at the front, and will sit on top of a pneumatic cylinder that will activate and provide a dump truck like motion when we are close to the CARGO BAY that will push it forward to dump.
These two mechanisms are described very simply because we don’t want to give you the answers… we simply want to help spur ideas by describing a simple solution that should not be overly difficult to build.
This robot can Cross the HAB Line (6 points), collect a HATCH from the LOADING STATION and place it on the CARGO BAY (2 points), and collect a CARGO from the LOADING STATION and place it in the CARGO BAY (3 points).
Applying our game theory tool to this conceptual robot, we should be able to achieve the following:
- cRi3D SANDSTORM Mode: 16 pts
- cRi3D Teleoperation Mode: 50 pts
- cRi3D End Game: 6 pts
The “cRi3D” would be capable of achieving 72 pts by itself in a match.
One thing to keep in mind when using an approach like this is to never close your mind off to eccentric and novel ideas. At first glance a crazy idea like one our students had, which we dubbed the “Japanese Parking Garage” seems unrealistic and out of scope. The idea was to build a robot that opened up and allowed robots to drive into it, onto the high level of the HAB, allowing all three robots to fit on the top level of the HAB.
Ideas like this are what make FIRST worth doing. A novel concept like this allows you to view the technical challenges in a whole new light, and when contemplating ways to accomplish something so outlandish, you might just stumble across real practical solutions for problems you are having with your current design.
Just remember our motto, and the second letter in FIRST:
Hopefully these articles can help new teams, teams in transition, or teams that are just looking for a new and improved way to approach robot design to learn and apply an analytical requirements based approach this season. If you want to learn more about this process, check out our presentation from the 2017 Purdue FIRST Forums on Robot Requirements! If you have any questions, feel free to reach out to us on Facebook or e-mail us at denkbots(at)gmail(dot)com!