Intake systems

[z_beeblebrox]

I found 842's intake to be very effective:

http://www.youtube.com/watch?v=P-2vE...0&feature=plcp

[Travis Hoffman]

48's intake wasn't wide at all (alas, it definitely held us back), but the double-sided intake conveyor was plenty fast enough. It was driven by a single RS-550 / 26:1 Banebots P60 combo. I'm still amazed that single motor/gearbox could drive that many polycord belts/rollers so efficiently (upper arm conveyor, figure 8 to lower arm conveyor, lower arm conveyor, and vertical conveyor down into the robot base).

For those not familiar, our 2012 robot's ball intake cage and shooter were part of a pivoting arm. Please see the attached picture.

Our original ball loading position was the arm tilted back to the vertical hard stop (aluminum angle piece with the black velcro rectangle in the pic). After collecting, we would then lower the arm to shooting position. We felt we could do better. We intended to find a solution to let us collect balls in teleop while leaving the arm in the usual front key shot angle, 48 degrees above horizontal (we planned the angle command to work out that way...surrrre).

The challenge to achieving this functionality was that whenever the arm was lowered to shooting positions, a significant air gap appeared between the upper ball conveyor and the motorized intake roller mounted in the robot base. This intake roller was mounted just underneath the hard stop and was necessarily independent from the conveyor belting system due to the changing angle of the arm. Without any improvements, balls being collected inward and upward by the intake roller and the vertical polycord belting could not reach the arm cage when the arm was in a shooting position. So how to bridge this gap?

Originally, we envisioned adding some kind of sliding curved lexan piece between the hard stop (fixed end) and the arm's upper conveyor frame (sliding end) to help divert the balls into the arm's conveyor cage. Ultimately, we found something much lighter and simpler worked great - a quarter-slice of blue (must be blue!) pool noodle velcroed to the vertical hard stop. You can see the strip of blue noodle peeking out on the far side of the stop.

As balls were pushed upward, the pool noodle deflected the path of each ball forward enough to get it to pop into the conveyor cage at any shooting angle we typically used. A simple, lightweight solution that provided a very important piece of additional functionality.

tl;dr - the addition of blue pool noodle backed by Velcro transforms any old fixed-length polycord conveyor system into a "virtual" variable-length system.

[M. Lillis]

Here is a video of team 177 at Beantown Blitz. Skip to 3:00 for the action, it is video from a helmet camera on the robot. There are a few points where it's effectiveness are shown, such as getting balls that are dangerously close to the opposite alliance bridge and in corners.

http://www.youtube.com/watch?v=Ce46-ydnY80

[TheMadCADer]

Originally Posted by BJC

While I think that this is the general tone I don’t think anyone has actually come out and said it:

Golden Rules of Collecting:
1. The faster the better. (Overkill after you get past 2x robot top speed.)
2. The wider/more tolerance the better. (Less driver precision = faster ball collecting)

By the way, those rules apply to every game – even when you can only pick up one piece at a time. Always keep in mind you have to pick it up before you can score it.

Regards, Bryan

I'd say one of the most important parts of collector design is making it simple and easy for the driver. In Rebound Rumble, the ideal collector allows the driver to touch a ball with that part of the robot, and then next thing they know, the ball is in the robot ready to shoot.

Ideally, the collector opening should be large, so the driver has a nice big, easy target. Also, when designing the intake there should be some consideration for the range of angles the driver can take to pick up a ball. For example, a 973/177/1477/2415 intake (118 had one too that I got to see, but they had to scrap it for weight) has a large angle that balls can be picked up from, since it can intake from the sides. This way the driver doesn't have to drive head on to pick up a ball, just basically touch it with a roller on any side.

It is interesting to use 1477 as an example here, because they didn't have their final intake for their first two regionals. For Alamo and Bayou, they used what was basically a large funnel with belts/rollers going up it. They had problems with this intake having a small angle of entry for balls, or else they would jam against the sides of the intake. The driver had to drive head on at balls, and line them up close to the center of the funnel. You could see that they were shooting much more rapidly and collecting many more balls by Championships and could even see a decent improvement at Lone Star, though they didn't win there.

Another trend among the more successful teams this year was an over-the-bumper intake. This had the largest impact for long robots, as they were no longer limited to the small gap allowed by the bumper rules, but instead close to the entire short side of the robot. Something that many designers didn't foresee, but I'm sure most drivers noticed, is that balls tend to get stuck against the walls, and they're hard to get when your bumpers are in the way. A through-the-bumper intake can't get the "edge" of the intake roller as close to a ball on the side of the field as an over-the-bumper can. This problem was also very apparent in 2010.

[DampRobot]

Originally Posted by TheMadCADer

I'd say one of the most important parts of collector design is making it simple and easy for the driver. In Rebound Rumble, the ideal collector allows the driver to touch a ball with that part of the robot, and then next thing they know, the ball is in the robot ready to shoot.

Ideally, the collector opening should be large, so the driver has a nice big, easy target. Also, when designing the intake there should be some consideration for the range of angles the driver can take to pick up a ball. For example, a 973/177/1477/2415 intake (118 had one too that I got to see, but they had to scrap it for weight) has a large angle that balls can be picked up from, since it can intake from the sides. This way the driver doesn't have to drive head on to pick up a ball, just basically touch it with a roller on any side.

While area is important, it counts in some places more than others. Many teams recognized that it is important to have as much area available as possible for picking up balls, but for some reason didn't think up an over the bumper intake. Some of those teams (like mine) chose a two sided through-the bumper intake (see 256).

What we all found is that when it came time to play at regionals, some area is worth more than others. Big movements, like turning the robot 180 degrees to pick up a ball, are far less difficult than the fine positioning needed to get a ball into a through-the-bumper intake. Although teams like 256 had more perimeter dedicated to picking up compared to, say, 254, but not as much contiguous area. That's what count's for drivers.