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Originally Posted by TheHolyHades1
That's certainly one thing we were considering. However, the problem is that if an opposing team's ball was to get into our system then we wouldn't be able to release it without shooting it, which would be a penalty on us. How were you able to avoid this problem?
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With our entire robot, our intake arms could raise or lower and allow the ball to be captured, or not captured. Our easy floor pass was raising our arms all the way a short burst backwards driving and the forward and the ball would fall on the floor where it was. In competition we wound up playing forward and generally shooting the ball, or playing defense and shooting over truss and didn't need the pass often. In my own opinion, the chance of an accidental "catch" was so slight we didn't worry about it. We would have to actively try and pick up an opposition ball.
Quote:
Originally Posted by TheHolyHades1
Interesting design, congrats on going to nationals and on making the news. ?
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Ha - we aren't - you can chalk that up to news reporter misunderstanding. We are in NY and went to the Troy, NY and Richmond, VA regional competitions. We did make it to semifinals and got to compete against the winning alliance though, and that was great fun. We live in a small area though, and were trying to drum up some interest in the program. I posted that video because it was the final configuration, and had some decent shots of the geometry.
Quote:
Originally Posted by TheHolyHades1
The problem that I'd think we'd have with implementing something like that is that you've got the pistons pointed horizontally (roughly), instead of roughly vertically as we do.
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It's all a trade off and I think either could work. We are more horizontal, and in fact I was trying to have the whole arm go beyond the pivot point as azcalg mentioned, effectively cam-locking it so we wouldn't need any latch. In the end, we were concerned that we would accidentally fire without a real latch if we got bumped too hard. with your specific robot and mounting points, you probably need to adjust some geometry until you find something that works.
Quote:
Originally Posted by TheHolyHades1
Could you perhaps post a bit more information about your gate latch system, and what you're using to latch/unlatch it?
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http://www.tractorsupply.com/en/stor...ate-latch-zinc
Fairly standard style gate latch. We actually used a small pneumatic piston to retract the gate latch. 1.5 in stroke or so, and 1/2 diameter? It was tough to get it working right though. We ended up angling the latch mount so the whole latch was mounted on an incline so the opening followed the arc of the launch arm. We also mounted a u-bolt to a back cross vrace across teh launcher arm as the piece that was latched.
DONT DO THAT.
Because it's curved it had a tendency to let the sides of the launch arms rock back and forth awkwardly. Instead - use a straight bar stock somehow- or we assume that would have been better. I can try and get a picture tomorrow to show what I mean.
Quote:
Originally Posted by TheHolyHades1
We will make sure we do that, thanks. Did you find that the solenoids were limiting you after you did this optimization?
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The force and sudden stop on this was able to rip through a number of plastic bearings. Don'd underestimate how much reinforcement you need. We were fine for a practice and had to strengthen it at competition because it was slowly dismantling itself.
Also - be safe. Don't stick your head over it. Our was certainly strong enough to seriously injure someone. We used a nylon safety strap around the whole launcher for carrying on and off field.
Yes, it appears solenoids were limiting us. We wound up using a storage tank on the typical low side behind the solenoid, and another on the front side of the solenoid on the launch tubing. That was plumbed straight in to the bottom of the piston and we did did not use any exhaust side fittings on one of the pistons. This was also pre-charged, and allowed a quicker transfer of air in to the piston. Our launcher would stay upright, so to retract we only plumbed one of the retract side cylinder ports to the solenoid.
We have a few post season ideas to play with and see if some other arrangement would have made for quicker cycling times on the pneumatics.