FBS braking + link system????

**grant_ploughbot** · 27th April 2004, 19:40

Im currently making a new 6kg full body spinner, i was wondering obout where i should locate the link, and so ive read through the thread about typhoons link and decided i will try and take that approach when i realised my centre axle is not at all big enough to have a centre flag.
So....
I have come up with an idea but i have large doubts to wether it will be accepted.
so here goes..
I am thinking of having my lingk, inside the spinner, but there are four 60mm holes in the top of the disc where ther link will be attached,
To stop your fingers from being disected from my hand i will have a servo--type mechanism that when activated with touch the underneath surface of the disc and then locate in a slot so that the disc is unable to move, and then the link is safe to remove!
With this mechanism inplace when the link is taken out, it will still be in place when the link is put in, altho there will be a locking pin in also.
I will also have a link on the underneath of the robot so that if it is flipped the link is still accesable.
Is this atall legal? i dont think it will be but its my only hope so far
Any ideas?
Thanks Grant

27th April 2004, 20:43

Hi Grant,
I dont have any personal experience of FBS but one potential problem i can see would be if the servo mechanism was damaged during a fight and did not engage properly it could be very serious if you stick your fingers inside to remove the link and the locking pin fails before power is removed.

Im sure someone better placed than me to talk about event safety will put a better answer up here at some point but i could not see many events allowing you to pass a tech check with this system in place.

**grant_ploughbot** · 27th April 2004, 20:52

yer that was my tought, even tho my lockin pin will be hand removed, i can locate it in aslong as the disc is not goin very fast, but the servo mech is a possible hazard!
Grant

**typhoon_driver** · 27th April 2004, 21:01

Grant we have to use large bearings on all our robots to allow us to get a link in.

The feather weight alone uses two 500g bearings which are completely oversized but we need that to fit a flag down. These are the same bearings used in the middleweight.

It is a real pain in the **** but I cant see anyone being happy about a servo mechanism working before the link can be pulled. Sorry to be so bleak!

Would u be able to fit a few wires capable of holding the current down ur shaft? That way, u could perhaps have the link on the very top of the robot and attempt to connect it in such a way that it doesnt spin, crazy idea but one of the only that i think you could use to get around the link problem.

**grant_ploughbot** · 27th April 2004, 21:20

Yer i think i will have to re make all the centre axle then, its only (dont laff untill u herd the rest) 10m axle, BUT..... it doesnt even need that centre axle. it has 7 outer bearingsalong the outer rim to cause minimal movement, and a further 3 around the top so there is no movement, the disc can be safely run withough the centre axle.
I have thought about having a link that is able to rotate, but it seems VERY complex for what im capable with the facilities at school, I am realy impressed with how it has turned out, up until i realised i had to put in a link :sad:
Oh and gary, where do you get those bearings from, and what are the dimentions and prices as i think this may be my only way around it.
If possible could you please email me at coop_bmx@msn.com on how you flag/link works with bearin stats?
Thanks very much for your help!
Grant

**typhoon_driver** · 27th April 2004, 21:37

so there is no movement

Im not sure that that is a wise idea, it is best to allow some degree of movement in ur disc even if jst a few mm so that not all the of the shock is taken by the bearings around the edge, so perhaps some shock absorbers?

We had the same idea as urself in extreme 1 with the middleweight however the small wheels that we had around the chassis were to absorb the impact and keep the disc spinning correctly so to speak. After 1 five minute battle, all of the wheels were bent or buckled out of position. True they were only an afterthought and werent very strong but still u might want to a have a slight bit of give somewhere.

Ill find out about the bearings and get back to you, although im not sure when that will be.

**grant_ploughbot** · 27th April 2004, 21:43

Okie thanks, well i have an idea for soft small wheels around the outer rim, but i fized with the idea of bearings, but if thats the problem you had then i will change my ideas bakck to smaller shock obsourbing wheels.
Thanks for your help
Grant

**julian** · 27th April 2004, 22:12

Perhaps for FBS the rules could be relaxed. The link is needed for the certainty of it being dead outside of the arena and for being retrieved whilst being nominally dead in the arena.

However, who in their right mind is going to go within a mile of a rogue FBS, let alone try and reach over it to pull out the link? You let the batteries run flat. Anything else is dangerous.