Re: [FTC]: Picking up balls
 

Not sure why its "completely illegal" in fact it doesn't look like it would ever hold 15 balls anyway.

- Andrew

Re: [FTC]: Picking up balls
 

It fits 21, therefore illegal. We got it fixed though!

Re: [FTC]: Picking up balls
 

These are all good ideas for picking up many balls.

Does anyone have any very simple ideas for how to pick up just one ball at a time, or much less? We were thinking a smaller conveyor belt, but there has to be a simpler way. From what I've seen, claws or shovels are too complicated or take up too many resources.

Re: [FTC]: Picking up balls
 

We used 2-1/2" PVC pipe with a chain and paddle system to elevate balls and make them turn a 90' elbow at the top. We used a second similar system to index/advance non-magnet balls after we sorted them, to move them to our crate-feeding mechanism.

1 servo for each. Not inexpensive, because the sprockets are either expensive to buy from Tetrix, or expensive to mill (very high failure rate in production), and requires a lot of robot structure to take up slack in chain. Also, engineering the mounting system for the paddles to the chain is a pain and requires grinding sprockets, plus cutting relief holes for the paddles in the pipe. Took us a while, and I think we'll go for open transport systems next year if one's involved.

Re: [FTC]: Picking up balls
 

Nice, but obviously very complicated.

I keep thinking there has to be a simpler way to elevate balls, but I'm not sure if there actually is one.

Re: [FTC]: Picking up balls
 

The biggest issue with claws and shovels is not their complexity, but rather how forgiving they are. With a conveyor, you drive over it and you pick it up. with a claw, you have to get the claw in exactly the right position. The result will likely give the drivers a migraine from the frustration of trying to coordinate arm and robot position while other robots are moving around. The best claws preform pickup operations directly in front of the robot like a conveyor belt, but with round objects there is the additional complication that if the driver hesitates upon contact with the ball, it will roll away from the claw. Luckily, The ease of use of the conveyor and the selective collection of the claw can be found in the roller/conveyor claw.

that being said, the only thing less complex than a typical conveyor is the degenerate case, a big wheel. It has only one moving part, but this is paid for by its large size.