I’d like to take some time to discuss some of the tricks we’ve utilized in the design of this robot.
First, let’s talk about the wings.
We found that the best compression for the ball in a wheeled shooter is 2″ (Thanks 868 and 2383). So during match play, the insides of the shooter and indexer wheels are 22″ apart. Unfortunately, this means the arms don’t fit within the frame perimeter at the start of the match. So, we created a system in which the arms will rest inside the FP at the beginning of the match.
To get the spacing right, we put spacers over a 1/4-20 bolt and wrapped electrical tape around. This puts the arms just so they rest against the tape, but can expand out. We can also easily alter this during the event if things get too loose or too tight.
In our starting position, the ball will rest on top of the outstretched arms.
At the start of Autonomous mode, we will drive the shooter wheels inward, pulling the ball in and spreading out the arms.
At this point, the arms will flex out to our preferred 22″ wheel-to-wheel distance. The arms will come to rest against another set of 1/4-20 bolts with spacers in place.
The shooter wheels will continue to draw the ball into the robot, and the indexing wheels (AndyMark Stealth Wheels, designed by CyberCard engineer Danny Blau) will pull the ball all the way in.
At this point, the arm turrets will aim for the shot, the shooter wheels will spin outward, and once they reach speed, the indexer wheels will push the ball up and propelled out by the shooter wheels.
We will put in a limit switch inside the yellow beak so the driver/operator can get feedback that the ball is securely in the robot.