A while back, I was brainstorming different ways to intake balls and gears with the same system. My team needed the ability to pick up both but only had space for one subsystem in the front of our robot.
The simplest solution would have been to have a classic floor gear intake which flips down to intake, then flips up and back down to outtake. Then, I could have simply had the shaft about which it flipped have rollers to intake balls. However, due to the positioning of our climber right above the intake, there wasn’t ample space for this kind of a system.
When intaking gears, it functions similarly to 1678’s intake from this year. The red roller drags the gear in, and the black 0.375" hex shaft (coated in a surgical tubing sleeve) pulls the gear up and into the intake. Then, it flips up, aligns with the peg, and flips back down to outtake.
Then, in order to intake balls, the red rollers in front actually flip up to ±4" from the ground, offering optimal compression to intake fuel. The back set of rollers spins inward, pushing the balls up into our hopper.
Prototyping showed that both the “gear mode” geometry and the “ball mode” geometry worked out on their own, but my team didn’t have time/resources to actually finish this project. It would be really fun to see this thing made, though, so if anyone wants the CAD let me know!
Really good design man. When narrowing down ideas for our offseason robot, I was having difficulty with determining what exactly if we wanted to both shoot and score gears. However, we chose gears only.
That’s a nice bit of cad and design. I think you’ll find what we did about the gears and a roller on top. The rollers will exert a downward force on the gear that will prevent it from going up and over the hex roller shaft. If you decrease the downward force on the gear, then the rollers won’t be able to pull it in against the hex shaft hard enough. It’s a very fine balancing act and is tough to pull off.
Our problem was slightly different - our initial prototypes put so much downward force on the gear that it would go over the lip on a piece of polycarb, even once it was ground down a bit.
We did something very similar, but instead we just lifted then entire gear mech up and then on the pivoting shaft there were rollers to intake balls. If we had used a motor to pivot up instead of pneumatics it would have worked much better, our specific setup made our pistons bend every match.
1058 encountered the same predicament. Three days before bag we wanted to switch to picking up gears from the floor while needing to integrate it as a ball intake.
The hardest challenge we had was that the intake needed to lift the balls vertically in the robot and our cyclone feeding system was directly behind this space. This meant we couldn’t start a match with a gear because we only had the depth the size of Fuel and it would need to pivot through a vertical feed roller. It also meant we couldn’t intake balls while holding a gear since the gear intake roller was doubling as a vertical roller as well. We felt it was a decent compromise to intake balls 50% of the time since it was such a late addition, our shooters weren’t operational, and gears were the primary function of our robot.
We worked to design a one way door on the back of our gear tray so it would start sticking out of the robot. Funny part was we entered our week 1 district with no ability to start or collect gears since this mechanism wasn’t completed and during load in night we worked in our pits to get it completed. Hit a peak of 7 gears in one of our qual matches.
This picture shows the intake in the ball position (all three rollers in line with each other).
This picture shows us at the start of a match with a gear sticking through the one way door.
The video gives you a glimpse into what happens during autonomous. This routine wasn’t repeatable without sensors on the roller so we instead rotated to the floor, spit the gear out slowly for a second, and then drove forward to recollect the gear before each routine. After this was taken at around 8pm on load in night at GSD, we swapped all of those red 3D printed spacers for two stacked plates of aluminum to make that tray/hinge section more rigid.
Your system looks very clean. I really admire the use of the round stock as the floor for the gear. After St. Louis we have since struggled with keeping the edge on our gear tray functional. At our first off season we hit the semis and kept failing to pickup gears since the lexan edge had worn down and had chunks missing.
I think the design choice for air was a good one with that setup. The only drawback I can see from that picture is that it appears as though the pistons are mounted so that they over-center.(meaning the end of the actuator rod pivot crosses below the axis of rotation for the device on that hex shaft) I am sure raising the tail end of the piston would have helped with that behavior. I see one side had a motor in the way of doing that but that could be moved in another iteration in the future.