Power/failsafe LED

[roger_plant]

Power/failsafe LED

Elisabeth,
WBCs ram is hydraulically tested to 150 bar, more than twice its working pressure.

[stu]

Power/failsafe LED

My God -

The only rule I have suggested changing is that the safety links are altered so they are removable, in an emergency, using a 10 foot long pole with a hook on the end, and the gas turned off by the same action.
I will not insist on that this year but will next.

Any robot that deliberately attacks the link would be disqualified,

Do hope your having a laugh.

The safety requirements Roobts have at the moment are good enough. The LED light addition is to help the roobteer and others know if the robot is alive or not when doing anything. A standard lighting rule should be made for the LED lights. A certain light for when the roobt is alive, or just RX on or in failsafe mode.

You start making and deactivating robots using a 10foot pole - then the hobby turns into who has the best balance skills to pull their link out.

Tis getting a bit silly now. How about we make RC ejection links. Press a button and your link auto pops out? Anyone for this rule?

Mr Stu

[kaideejee]

Power/failsafe LED

Sounds good to me now Ive ordered my brand spanking new 6 channel system

Ahem. Sorry.

-- Kev

[jim]

Power/failsafe LED

I was just thinking about that Stu. Ive got some small cylinders which could do the job - just have to be careful they cant fire when youre inserting or removing the link manually.

[mute]

Power/failsafe LED

Roger, get over what??? And please dont pretend that you know me because you dont.

Exactly what are you going on about with regards to bomb disposal? I thought we were talking about Robots, safety issues and 10ft poles...

[stu]

Power/failsafe LED

The 10 foot polls will need sharp edge protection.

Mr Stu

[fwsorg]

Power/failsafe LED

I thought it might help to clairy were the conversation has come so far so that people dont have to trawl through the archives:

Power LED- The majority of people accept this is a good idea, on the proviso that:

a) An LED on means there is power in the robot.

b) An LED off is not sufficient to claim that there is no power in the robot- untill the link is quite clearly out (and even then previous posts have suggested that some wiring is sufficiently appalling that there may still be power to the robot) the robot must still be treated as dangerous.

Boats hooks and links- the idea seems to have been thoroughly poo-pood on the grounds that:

a)The plates can get mangled and bent so that they become stuck in the robot.

b)The idea of enforcing a no link attacks rule is very difficult to enforce, and will open up a whole avenue of possible technicalities and appeals to fight outcomes.

Lets not let this get personal, afterall were simply trying to make the sport safer and more enjoyable!

[Guest]

Power/failsafe LED

If the failsafe LED only is advisory, then the only thing we need to discuss here is hints about how to fit them. It doesn€™t matter what colour they are, as long as the builder knows what they mean!

But the problem concerning the main power LED is something that we preferably would solve here and now. The way that makes the most sence to me is the following. You connect a normal changeover relay in parallel with the main power circuit, a small LED to the normally open connection, and then feed the LED from a separate battery (possibly the once powering the reciever).

This means that the robot is only safe when the LED is active (which only can happen when the removable link is out). No matter how much you argue about it, if the LED is active, the robot is safe.

Feel free to critisize any of this...

[jim]

Power/failsafe LED

Did you mean the normally closed connection, so the LED is active unless main power is on?

Even so a failure of the relay or a broken wire could cause the light to come on...

[ewan]

Power/failsafe LED

Ok, before this LED topic came about, we didnt have too many concerns about robot shut-off safety. Most robots are fine as they are. As long as you can disable a bot in practice, you wont need 10 foot long poles... The LED is a good idea, but wont account for all safety problems. I think we should just keep with the good old fasioned removable link and maybe LED for now.
(Has this topic been resolved yet?)

[Guest]

Power/failsafe LED

Jim, youre absolutely correct. The LED should only be active when the main power is off.

[blazerbotics]

Power/failsafe LED

hmm not a good idea. we have about 7 LEDs that come on inside the robot when the link is in. If the robot was on, and somebody saw a light from inside the robot they could assume its safe. What would the LED be powered by when the robot is off? as we disconnect our batteries to charge them.

[geoff]

Power/failsafe LED

The only problem I see with this is the moment you introduce another component I.E. a relay into the equation you have one more point of potential failure. Let us assume for a moment that this relay is damaged in combat, or just fails, there is the real possibility of you having the situation where you have a robot with an LED that is on (safe in your eyes) but in reality you have a fully powered up robot on your hands!!! As for relying in a separate supply for said LED...yet again, something else to fail.
Ever heard of K.I.S.S. ?...Keep It Simple Stupid!(no offence intended) All that is required is an LED wired across the side of your removable link that is isolated when the link is removed and 0V. As a back up we use 2 LEDs in parallel, just in case one does fail.
Link in.. circuit closed..LED on, robot live! Link out.. circuit open..LED off, robot dead!
I know this is not the perfect solution and there is still the remote possibility that an incorrect indication could occur but there is a lot less of a chance than by using your idea!
We use this principle on both our heavy and featherweight machines and we have NEVER had a problem in the arena or when submitting the machines for tech. checks either at RW or live events.
In conclusion, the whole point of a visible indication of a powered up machine is exactly that...an INDICATION ONLY! There is no substitute for safe working practice and proper observation of ALL safety procedures when arming / disarming your machine. I wouldnt trust my own, or any of my teams safety solely to an LED, on or off!
Just my two pennies worth!
Geoff,
Team Scorpion,

[ukrobotics]

Power/failsafe LED

I have to agree with John Frizell & Roger Plant about the power LED - it€™s not a good idea. Despite its intended use, the simple fact of the matter is that over time people WILL become complacent and rely on the LED as a safety indicator. One of the main reasons for having a removable link (apart from being more difficult to damage) was so that people would have a visible indicator of if a robot has power or not and this cannot go wrong like an LED can. If the heat of the moment is enough to cause someone to forget a link they put in only a few minutes ago, I find it difficult to contemplate that theyd even notice the LED was illuminated, and on a bright summer day nobody would be able to see it anyway - not even an ultra bright one.

Although in theory the link plate thing is a good idea, in practice I feel it will be very difficult to implement, especially for beginners and people with odd shaped robots.

Here€™s another option ..........

How about instead of using an LED power indicator, make sure links are placed in an easily visible location, and then protected with clear polycarb so at a glance it will be much easier to see if a robot is powered up or not. This method is also very reliable as the indicator is the link itself and as it does not need to be illuminated to work, it can be seen just as easily on a sunny day as it would indoors or when it€™s cloudy.

As for deactivating robots which have died in the middle of the arena, what Jonno said is exactly what the power LED should NOT be used for, After a fight when robots are immobilised, and a member of my crew has to go in to make them safe, a quick visual check, tells the person which ones are definitely live and which ones are (visually) dead. And so which ones to go for first.

I don€™t know if this has occurred to anyone already but surely for events such as Roaming Robots which are held on a regular basis wouldn€™t it be a good idea to build a large heavy robot with a big scoop/shovel, specifically designed for moving dead robots? Im thinking of something very much like the thing Derek Foxwell built which was used at the Robotwars S7 Qualifiers for the same purpose.

Using an ROV to make robots safe would be far better than sending people in to do it, and much easier than fiddling around with pulling links out with long hooks. It would also be entertaining for the audience to watch. Any dead or out of control robots could simply be driven to the side of the arena and pinned against the wall while the link is pulled out.

I know this would not be suitable for every single event, but I€™m sure it would be feasible for the regular event holders such as RR. As for events without this system in place, there are usually other robots that would be able to do the same task (albeit not so effectively) and of course if that doesn€™t work there is still the option to wait for the robots batteries to run out.


Dominic

http://www.ukrobotics.comhttp://www.ukrobotics.com

[Guest]

Power/failsafe LED

Alan, I said that the LED could possibly be fed from the same battery powering the reciever.

Geoff, when a relay fails the odds are that it will spring back to its unengaged position. But the problem with your way is that if the LED should fail, then you dont know wether the robot is safe or if the LED has burned out.

Anyhow, I cant see how my way could increase the risk of an incorrect indication.