In addition to running around the track or herding, does your team plan on hurdling the ball? How?
We went with a quick pivot arm that grabs the ball from the ground, holds it on our bot, runs around the track, then lifts and hurdles the ball. Next, repeat steps all over again.
We also have the ability to knock balls off the overpass and place them at the end of matches also.
I have seen a lot of shooters/catapults which seem more effective. However, I am curious as to how they will place or remove balls from the overpass.
We’re planning on lifting the trackball over the trellis, about halfway, and then dropping it over. We can also place it back on the trellis at the end of the match. Ours is a forklift device with a saucer shaped vacuum.
We have a catapult shooter type robot, with a patent pending gizmo that knocks the ball off, and we’ve accidentally placed the ball on the overpass several times while testing the shooter.
Our machine will definitely have an arm capable of placing the ball and hurdling. Depending on weight and time there will be a shooter added to that arm.
Our team is using a pneumatic-operated catapult. However, to get the lever arm long enough we had to make our robot extend to twice it’s starting size at the beginning of the match. The catapult arm will start raised at an angle, then drop down once the match starts.
We’re using a catapult and a seperate knocker device mounted on the top of the catapult frame (so far) that will knock the ball off during hybrid mode. But other than really really accurate shooting we won’t be able to place the ball back without help, hopefully we’ll be able to hurdle fast enough to make up for it though.
Our robot is using a spring/piston method to fire the ball over. It will sit 3 inches beind the ball on our composite arm:D and be raised by the window motor.
I’m not sure just what the difference between a ‘catapult’ and a ‘shooter’ is meant to be, but we are shooting the ball with a catapult-like mechanism powered by pneumatics.
We have managed to land the ball on the rack a few times during testing, although now that we have increased our shooter’s power it would actually be quite a challenge to get the extra four points you get for putting it up on the overpass. We are more than willing to sacrifice four points (12 for leaving it on the rack - 8 for just shooting it over) for the speed and overall efficiency (fun!) of shooting.
As for knocking it off at the start of the match… a 2"x24" cylinder at 20 psi will only use as much air as a 2"x8" cylinder at 60 (about 5-10 seconds of compressor time). You can also set the cylinder up to be single-acting (note that this is different from using a single-acting cylinder, which is a no-no), so you don’t need to waste air pushing the rod back down. It is still a lot of air, but not so much that we won’t be able to recharge in time to shoot.
We figure that if the compressor recharge rate (approx one shot every 20 seconds) is the limiting factor to our ability to score points that we’re probably having a fairly successful match.
despite my madman ranting and crazy talk about a awesome shooter, we have built what is looking out to be a pretty functional lift arm claw … thing…
we just have to get he chassis painted with racing stripes first…
I am curious to see how dependent catapult/shooter robots will be where someone on their alliance needs to bring the balls down from the beginning of the match either during autonomous or tele-op play. If they cant do it and teammates cant, then what?
So far, a lot more lifting arm type mechanisms than anything else.
WC
