Multi-Tetra Grabber - free to a good home!

[Mr. Lim]

The rumour (http://www.chiefdelphi.com/forums/showthread.php?p=367036#post367036) is true!

Team 188 will not be attending championships for the first time since its creation in 1998. Despite this, we feel it's been one of the most enjoyable, and successful years we've ever had! We've had a chance to see first hand the kind generosity shared by FIRST teams, eg 22 who took us into their homes so that we could compete at the SoCal regional.

We know our season is over, but it's not over for 340 teams waiting to compete in Atlanta! So now it's time to give back to the FIRST community...

We're hoping to help any Atlanta-bound team who may need a tetra-grabber. We have a spare tetra grabber, that can hold two tetras, and drop them independantly. A picture is attached to this post.

If your team needs it, or wants to try it to help your robot - the tetra grabber is yours!

Here are a few details about the offer:

- grabber will be delivered to Atlanta by a Canadian team attending the championships
- we will include, with the grabber, all BOM and cost accounting for materials and labour on CD and hardcopy
- we will certify that it was constructed within the legal time frame parameters
- the grabber will be completely assembled and should "work out of the box"
- there is no obligation to even use the grabber (if you try it, and it doesn't work well, or the way you want it to, put it aside and forget about it! We want to help, not give you more headaches :D )
- no kind of recognition is necessary or is expected
- this offer is open to any team attending Atlanta
- we only have one grabber to give away, so if more than one team is interested, we will try and give it to the team that "needs" it the most

If you have any questions about the grabber or the offer, please post in this thread, or PM me!

If you have comments/questions about rules and the legality, please post in this thread. (http://www.chiefdelphi.com/forums/showthread.php?p=367036#post367036) I would like to keep this thread dedicated to anyone who might be interested in taking the grabber.

-SlimBoJones...

[Kevin Sevcik]

Slim,

Teams will need a bit more info on the grabber before they consider if they can use it, I think. Specifically, how much does the grabber weigh? Roughly how does it work? What motors or pneumatics are used to actuate it?

[Mr. Lim]

Slim,

Teams will need a bit more info on the grabber before they consider if they can use it, I think. Specifically, how much does the grabber weigh? Roughly how does it work? What motors or pneumatics are used to actuate it?

Kevin,

Thanks for the post =).

I didn't want to clutter the initial one with technical details.

How does it work: Three teeth hold each tetra under the top apex in the grabber. The teeth are mounted like "carabiners," which means tetras can be shoved into the gripper from the bottom, the teeth fold upwards during tetra load, then automatically fall and lock into place. This happens even while the robot is disabled - the "carabiner" action is totally mechanical. To release tetras, the teeth are pneumatically released downwards, allowing the tetra to fall through. There are two independant sets of teeth, allowing two tetras to be loaded, and independantly dropped. Hopefully I can post some movies to demo the loading and dropping process.

What motors or pneumatics are used to actuate it: The grabber is actuated by pneumatic cylinders, all of which are included and integrated into the top of the gripper. There is one cylinder for each set of teeth - one cylinder releases the bottom tetra, one cylinder releases the top tetra. In order to get it running, you will need to wire two solenoids, and run the four hoses into the top of the gripper. We can also supply our RC user code that controls the gripper cylinders.

Weight: Pending an exact measurement :o

-SlimBoJones...

[J Flex 188]

Just some qualitative data to go along with what's been posted already.

I drove the base of the robot for three regionals and at our best performance in Waterloo. While there, this grabber was capping 5-6 tetras a game and loading 3-4 times. Combined with a turreting base this could prove very useful. We finished 7th in Pittsburgh and reached the Quarterfinals, 6th in Waterloo and reached the Semi Finals and somewhere in the 20's in So. Cal but still reached the Semi Finals (must have been the weather)

There are a couple of other nuances to the grabber that could probably be mentioned but perhaps I will wait until we know who is willing to give this design a shot.

[Mr. Lim]

Here's the grabber performing a "split."

www.team188.com/videos/Split.avi

It's a 14 meg AVI, so you may want to right click and save.

-SlimBoJones...