OK everybody, Kiryu (pronounced key-eww), our 2005 bot from Team 1132, RAPTAR Robotics, is finally complete and has shipped away!
Luckily, I grabbed a few snapshots of Kiryu a few hours before we shipped, so I thought I’d share them with you! Please post comments.
For those of you who saw us at the DC Scrimmage, much progress has developed since!
More on this after some pictures!!!
Kiryu in its starting pose:
Kiryu with its new manipulator locked into position (more details on this in a minute!)
Kiryu blocking a standard goal:
Kiryu with arm fully extended:
Kiryu’s Controls (You cant quite see how clean they are)
“The Piston” (Note the reed switches…)
And finally, a closeup of Kiryu’s manipulator:
So, here’s the “story of our manipulator”.
After DC, it was evident that a bar would not be efficent enough for the task we were trying to complete. We needed something that would align the tetra with itself, give us more distance from the goal, and maintain the tetra alot better. Within One Day, we fabricated our “tri-rocket launcher” manipulator out of PVC, Lexan, McMaster tread, and three plastic baseballs. FIRST is probably the only cause for WalMart to have customers buying platic baseball bats and balls at 11 at night for building a robot! Anyway, we tested the system today and it worked great!
With that said, I thought I’d give a nice thourough explination of our robot, our strategy, design, controls, etc.
After we went through the phases of analyzing the game and formulating our strategy, we came to the conclusion that we needed a bot that was fast and accurate, worked with one tetra at a time, and could cap on all goals. We also wanted the design to be able to function defensively without any change in hardware or mechanisms.
Once we had our strategy, it was obvious that we were going to need a good lift. We analyzed several different types of lifts, but we liked the 4-bar style lift the most. Both for its simplicity, and for its easy integration with pneumatics.
Enter CAD. For our First year, we’ve finally been able to fully utilize CAD to design all our assemblies and the final result after construction was amazing. it proved to be one of our most powerful tools this year.
So, here’s some info about how Kiryu’s lift works. Kiryu’s lift functions on a multi-positional piston that extends the manipulator from around 25" for ground level tetras to about 10’ 2". We used a 24x2" piston running at about 40 Psi. After evaluating our multi position setup, we came up with a solution that would both double our air supply, and increase our positioning accuracy. The solution is to “single power” the arm. In other words, the piston extends by adding pressure into the end of the piston, and exausts by venting that pressure. the forces of the arm on the piston are more than enough to retract it.
Now if that positioning setup wasn’t enough, it gets even better. All 6 of the reed switches from the 3 pistons we ordered are positioned along Kiryu’s main piston at preset heights. Basically, they’re setup so that (for example) “switch 2 will trigger when the arm is at loading zone height”, or, “switch 3 will trigger when were at standard goal height”. This allows our drivers to simply tap a button for the position they are seeking and the piston will align the arm accordingly. One more nice thing about the positioning system is this: Our manipulator has been lined with sensors to detect when it has a tetra within its “grasp”. This tells the positioning system to seek a different reed switch for proper positioning. For example, if the robot does not detect a tetra on it, and the human presses “standard goal height”, it will seek to switch 3, which will put the manipulator at a height just above the standard goal. However, if it sees that it has a tetra, it will seek to switch 4 instead, which will put the arm at a height such that the base of the tetra hangs just above the goal.
(I hope the controls awards guys get a good look at what we’re doing! Has anyone done anything this level with pneumatics before? I’ve heard of other teams using multipositioning, but none with such a setup…)
Kiryu also has a series of autonomous modes (some still in progress :yikes: )
But they include:
-Capping a vision tetra (our camera code is working )
-Working with the hanging tetras…in some way…
-Capping the starting tetra quickly onto a goal
Well, I dont have time to explain much more, but please, post comments and questions.
Thanks all, and good luck!
See you at VCU! (and hopefully Champ! )