Nice!!! but the real question did it work well? Because We had a similar idea to it.
For concrete jersey barriers?
I would be carful with that getting ripped off your robot during collection.
When building a ground-picker-upper ask yourself would this break if a robot hit it square on going 10fps?
at this point the grabber is not completed. it needs more bands and they will be tighter. nevertheless, it grabs, and almost turns the tubes. fine tuning will be done. Effective? Yes i think so.
Is that some type of urethane tubing you are using? If so, how did you weld/join yours together, they look nice and neat.
The orange cord is called polycord you can order it from Mcmaster-carr, it is joined by heating the material up, joining it, then letting it mold together and cool. Works really good for a variety of FRC and other applications.
This looks really HEAVY. Whats it weigh in at?
I agree with sean it looks really heavy ,but if you are able to lighten it i think it will be very useful for manipulating the tube.
I agree also, It seems that straight roller supports mounted nearer to the axles of the inboard pulleys would make it much lighter.
If you mounted the larger pulleys concentrically with the pivot for the corresponding ‘finger’ the belts would maintain tension as the grabber opens and closes.
It weighs in less than 5 lbs and the reason for the offset of the drive pulleys is so we can tension it. The arms wont move during the game.
You’ll find it on mcmaster-carr under urethane belting. Its very useful for not only conveyors but also it is a lightweight way to power something. I have seen teams use it for their drivetrain. I wouldnt recommend that though because a lot of issues can prop up with that.
The way we mold it, not the team whose photo this is, together is we took a piece of aluminum block. drilled through the center of it with a bit as big as the diameter of the polycord. then we sliced the block in half at the point where it was drilled through. then we melt the polycord and put it in between the 2 pieces you have left and you get a nice and strong connection.
Do you have a picture of this? I would love to see it!
We had great success with the Art Dutra Method.
We didn’t wait half an hour (maybe 5 minutes) and never had one break. Also 10% shorter than the run is too short, they run just fine (and it doesn’t require super human strength to get them on) at 3-5% shorter than the run.
This entire thread is very helpful when it comes to polycord.
I think the concept is good but it could be cleaned up a bit…
is this just a prototype?
HINT: the tube surface is very different than in 07 and I believe that wheels work better than belts. Also in a collision belts may come loose easier than wheels…
wait the gripper opens and closes? or is stationary??
I’ll have to give your method a try. Trying to force to ends together by hand with a heat gun or soldering iron is a pretty poor way to join polycord, as it is apparently called.
We set both ends on fire and then put it in the assembly. We did it this way in 2009 and had like 20 long strands of polycord and not one has broken yet but they are starting to stretch a bit. We also threw some extra strands on there in case one broke we could replace it without having to take the whole conveyor system apart.
Looks great Guys! who did your welding?:yikes: