In autonomous mode, Pathfinder is often positioned in front on the Cheval de Frise to smoothly cross the defense in autonomous. They can also cross any other static defense (and Portcullis) in autonomous if need be.
In Tele-Op, our drive team is skilled at directing Pathfinder through cycles of shooting in the high goal, retrieving a ball in the neutral zone, and continuing to breach by going over an undamaged defense. We can reliably do four of these cycles per match. If our robot is solely shooting and being fed boulders, it can make seven high goal shots. Our catapult has an 85% accuracy, and shoots from the batter. Pathfinder can easily cross the Portcullis, Cheval de Frise, Ramparts, Moat, Rock Wall, Rough Terrain, and Low Bar. With assistance, the robot can damage the Drawbridge and Sally Port and likewise assist other robots to damage these two defenses.
At the end of the match, Pathfinder has a reliable and awe-inspiring climbing arm that can scale the tower in under 10 seconds. We are very proud of our robot and we will be competing in St. Louis, MO at the FIRST World Championship Competition.
-The SOTAbots, FIRST FRC Team 2557!
This week took an unexpected turn when one of the bearings inside our mill broke, so we had to do without one for a few days, but now we have a better one! One of our mentors had a Bridgeport that they didn't need anymore, so they gave it to us, which is we are sooooo thankful for!!!!! Despite this incident, the build team has moved from the prototype bot to the practice bot.
The pillow blocks for the drivetrain have been welded on, as well as the uprights, catapult mount and arm mounts. Chain tensioners for the drivetrain are about halfway finished, but it's undecided whether or not we will use them on the final bot, and the linear actuators should be done today or tomorrow. Soon we will completely finish our practice bot and we hope to have time at the end of build season to start using our final bot!
Build Team has been rigorously working to finish our prototype robot, and has re-designed multiple mechanisms to better complete the game tasks. Because of complications regarding the size of the flywheel shooter, we are now using a catapult method. For the catapult, we were originally using surgical tubing as a tensioner, but are now testing springs which seem to be more efficient and reliable. The boulder intake system has also been drastically modified. A 32 inch long piece of box tubing, on both sides of the robot, connects to a platform near the ground. This platform is currently made of polycarbonate, but may change to a thin sheet aluminum for durability. A PVC pipe wrapped in polycord is adhered 9 1/2 inches above the platform to grip balls and hold them against the bumpers so we can cross defenses with them. Our climbing method has not undergone any major adjustments, however the linear actuators' we have been making for the intake arms have been shortened in length.
To mount electronics, we have collectively decided to place triangular polycarbonate structures over the drivetrain to utilize available space. The plates are mounted at an 130 degree angle on either side of the wheels and so far, we're able to place 7 talons on one side, and the bridge and power switch on the other. For the roboRIO, PDB/PDP, and voltage regulator, there is a plate underneath the catapult for easy access and protection. Lastly, we've been working closely with CAD team to finalize our electrical and mechanical drawings in Autodesk Inventor, and to help us catch flaws and conflicts before we cut material. Next week, we plan on having a welded frame with the drive train working, and the linear actuators complete. All in all, this week has been very productive, and we can't wait to continue with build season!!!!
Over the past week, the Build Team has been prototyping and testing multiple intake and shooting mechanisms for our 2016 bot. Our current strategy includes the ability to go under the low bar, shoot in the high goal, scale the wall, open the portcullis, and drive over defense categories B and D. To accomplish these tasks, our final design must be within 14 in. tall, 3 1/2 ft. long, and 2 ft. wide. This requires that all mechanisms must be simple and low-profile.
For shooting in the high goal, we plan on having a polycord belt intake in the back of the bot connected to a flywheel system in the front. However, if the modified prototype does not perform correctly, we have other design ideas including a catapult and kicker (both have been prototyped and work effectively). To acquire boulders, we'll either drive up to them and start the belt intake, or have a retractable cube that folds down from the top of the bot, grabs the boulders, and then dumps them into the shooting mechanism.
To get under the low bar, the top of our robot will either have an aluminum bar or polycarbonate sheet for the flap to slide over. We haven't constructed a final design to hang on the pull-up bar but do have a few ideas. Most likely, the bot will have an extendable arm powered by a linear actuator, which will also have the ability to open the portcullis. Our second idea is to have a piece of thin, lightweight material meant to get a hook (connected to a winch with a rope-like cord) on the pull-up bar. Once the cord is hooked, the winch will be tightened to pull our robot up.
Finally, to drive over defense categories B and D, we'll have a 6 wheel pneumatic drive train. The total length on each side will be around 34 inches, and a total of 5 inches thick including the gearboxes. This design has been prototyped with high traction wheels, but not pneumatic wheels due to a backorder. Regardless, build season is off to a fantastic start!
The first week of miniterm has been very productive for the build team! We have been working on reorganizing our shop and nesting after the move from Stewart Middle School this summer. The shop looks more like home now and everything is in its proper place. In addition to moving, students have been working on fixing all of the tools that were damaged during the move and building our Mary Bridge robots for Mary Bridge Children's Hospital! The robots are coming along nicely and are built so the patients at Mary Bridge can play soccer with each other. Overall we have accomplished a lot this week and we cannot wait to find out the game tomorrow and start building our robot!!!
Powered by SOTAbots students