Tethers

[Mouldy]

Does a bungie cord in a single acting system count as a teather? I pressume it will, but better safe then sorry!

regards
Dave moulds
Team Turbine/PLF

[jamesb]

dont know, but hearing the latest discussion at fra meeting, I think it maybe not.

Id not worry too much for now though, if you enter the robot early and explain the mechanism to the evnt orgainiser they can advise you what they will need for that event.

[killercarrot]

Is there any more information on tethers particularly with the FRA event coming up.

[jeremy_cuss]

Rob,

My understanding is that you cant have a new rule without specifying what is required. It hasnt been done yet. If you volunteered to produce a draft rule, Im sure that the executive committee would bite your arm off.

The current suggestion, as I understand it, is that individuals are urged to come up with their own solutions to the problem. From that a rule change will emerge.

There would need to be some time to fit a tether before the rule became operational. In my opinion I dont think that we will have a new mandatory rule for tethers on flippers in 2004 - but I may be wrong!

Jeremy

[blazerbotics]

i believe there is testing being carried out on different materials, including seatbelts. I havent seen any robot with them in yet.

[grant_ploughbot]

oh am i correct in thinking, that if seatbelts are to be used as tethers, then natrually people will go and buy them cheaply from a scrapyard? In which case they may have been in a crash and now unsafe to use? Just raising a possible saftey issue as i saw on a program the other day that seatbelts are unsafe to use in a car crash more than once.
Grant

[julian]

Most cars in scrap yards have not been in crashes. In fact, in the case of most Rover Metros, they went from factory to scrapyard with suprisingly little in between.

[kronic]

Weve got a seatbelt as a tether in the new Kronic. Havent tested it yet though.

Dave

[arfamortis]

I have been tasked by the committee to attempt to find a solution to this problem, now there have been several tests done, the results of which are inconclusive. I can catergorically state that steel cables are not acceptable unless they are in a relatively straight run and are correctly terminated with a thimble of the correct radius for the size of cable and the cable is of certified lifting quality. Ubolt type clamps are not acceptable due to the stress levels generated by them in a point contact.

Seat belt webbing may be acceptable, again consideration should be given to the terminations, I would reccomend using the web adjuster buckles that tighten on impact to form a loop, the ends should be stitched, not heat sealed.

Aramid rope (Kevlar) is acceptable, again providing it is correctly terminated. I have a lot of experience with Kevlar cables and the only way that you can guarantee that the end will not let go is by using a cone or wedge anchor fixing. Knots would not be acceptable as they will loosen no matter how tight you make them.

Our official stance at the moment is that tethers will remain advisory only. This may change in the future.

Personally I am not even sure that they are needed at all, as all arenas should be able to contain failed weapon missiles, otherwise that weapon should not be permitted to run in an arena of insufficient strength.

Arthur Chilcott
FRA Chief Judge.

[arfamortis]

PS
A thimble is the tear drop shaped eye that you see in spliced steel cables in case you ask.