Dissadvantages of Suction?

[Dumper FTW 435]

Originally Posted by liam.larkin

I would speak to the eSTOP people first ofcourse. I believe they use this exact function on their own robot so they would be able to tell you in more detail.

Thanks, I'll look into it

[Jon Stratis]

For what it's worth, we looked at suction pretty hard in 2007, and ended up abandoning the idea. We could never get a system together that could reliably pick up the tubes without requiring extreme precision, and the battery requirements for it are pretty intense. We've steered away from suction ever since.

[camaro 20]

my team tryed out a suction system where we used a shop vac and a mask used in cpr. the suction held when we shook the tubes back and forth but only would drop when we turned off the power. one of the proubles we had was going in with a suction method you had to grab the opposite end of the tube.

[thefro526]

The disadvantage of Venturi Driven suction is that it requires a Pneumatic System to function which means you're adding a minimum of an extra 10lbs or so if you have the compressor on board and a reasonable amount of air tanks.

There are other options available to create a reliable vacuum driven mechanism, perhaps the most common is to take a commercially available vacuum impeller and retrofit one of the KOP motors to it. The motor only has to run while you need the vacuum, which should draw less power over the course of a match than a compressor. This method has been used by teams in the past to hold Soccer Balls, Track balls, and Tubes so it's proven as long as you can get your implementation right.

One of the downfalls of suction is that the surface of the object has to be relatively uniform which makes positioning key. You may or may not be better off pursuing another option.

[Dumper FTW 435]

Originally Posted by thefro526

take a commercially available vacuum impeller and retrofit one of the KOP motors to it.

We have considered that idea. What would you suggest we try? I know a lot of teams have used shop vacs in the past

[thefro526]

Originally Posted by Dumper FTW 435

We have considered that idea. What would you suggest we try? I know a lot of teams have used shop vacs in the past

To be completely honest, I don't really know. Most of the systems I've seen have used a shop-vac or other heavy duty vacuum.

[Chris is me]

Buy a shop vac from Home Depot and take it apart and you should be good. I don't have a specific model, but I heard that the model 228 used basically came ready for an FP motor retrofit out of the box.

That said, I would make sure you put a lot of thought into your cup design to make sure you're getting the best possible hold on the tube.

[IndySam]

last year we just ordered the impeller from the manufactures replacement parts website.

[Sunshine]

Ryan:

We used a vacuum system last year by making our own impeller. We took apart an 18volt hand-held vacuum and re-engineered their impeller for our purposes. It was created in our 3D printer at school. It worked great. I have enclosed a few picts of the system. If you can use the CAD files, I would be happy to pass them along.

[Vikesrock]

It should be noted that there will be significant differences between an impeller based system and a venturi based system as described here. You may not be able to get the same strong hold with an impeller based system.

[smileydude560]

We also used a vacuum system last year, but all we did was rip the impeller out of a shop vac and hook it up to a geared up cim. It worked pretty well, but we gained a reputation for our incredibly loud robot. You would also need a way to turn off suction. Last year, we used our kicker to get it off of the tubes, but I don't think using a kicker will be as good of an idea this year XD

[eStop Robotics]

Greetings from eStop Robotics!!!

Thanks to Liam for suggesting our Custom Controls Interface (CCI)!

Last year, a team we sponsor, Royal Assault Team 357, was able to use the impeller and tubing from a vacuum cleaner for a suction device. They were able to control it using custom controls.

This year we've introduced a new product, the CCI, for just this purpose. It is a simple, effective way to add custom controls to your robot.

The CCI has 12 digital inputs and 4 analog inputs. No special SW or drivers to install. It works with your Driver Station PC out of the box. Your cRio programming is also no different than using a joystick, the same functions are used for the CCI as a regular joystick.

The CCI can be used to wire up switches for your controls. Using the CCI and a switch, you could turn on or off your suction device when you want to during a match.

http://www.estoprobotics.com/estore/...d&productId=33

Good Luck to all the teams!!!