YBW Featured kill chord alarm

jrudge

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There is a kill chord alarm featured in this issue.

YBW are involved in the development and have dedicated several pages to it.

The idea seems OK - alarm the chord so it goes off if not used.

The innovation seems to be magnets that pull together when the chord is under strain .... around your leg...... No connection ... not being used and alarm goes off.

Has anyone ever put a kill chord round their leg? I haven't - I just clip it to the top of my shorts( indeed the Williams ones are not long enough to do anything else) and the ladies usually clip it onto their bikini where the two cups join.

The idea of alarming the cable seems a good one - but the suggesting you attach the thing to your leg ( and this is the only way the thing seems to do its job) seems totally flawed.

Maybe I and all Williams users (chord length) are the exception?

I can see that something that detects if the the chord is extended in some way and hence likely in use could work well - but this seem too specific for a method of attachment I have never seen.



Jeremy
 
There is a kill chord alarm featured in this issue.

YBW are involved in the development and have dedicated several pages to it.

The idea seems OK - alarm the chord so it goes off if not used.

The innovation seems to be magnets that pull together when the chord is under strain .... around your leg...... No connection ... not being used and alarm goes off.

Has anyone ever put a kill chord round their leg? I haven't - I just clip it to the top of my shorts( indeed the Williams ones are not long enough to do anything else) and the ladies usually clip it onto their bikini where the two cups join.

The idea of alarming the cable seems a good one - but the suggesting you attach the thing to your leg ( and this is the only way the thing seems to do its job) seems totally flawed.

Maybe I and all Williams users (chord length) are the exception?

I can see that something that detects if the the chord is extended in some way and hence likely in use could work well - but this seem too specific for a method of attachment I have never seen.



Jeremy

We have thought about this too. The finished production version of Lifecord comes with a second 'lifejacket' key. This has a shorter neck to it so that it shuts off the alarm as soon as its attached even without any tension on the line.

This 'lifejacket' key can be fitted to a split ring or carabiner style clip so you can attach it easily to a lifejacket, belt loop or even a bikini (if you must!).

Full details of this and other details of the production ready Lifecord as well as the final cost and how and where to buy it will be published in the next (March) issue of MBY. The story in this issue (Feb) was to introduce the concept and explain how it came about .

Hugo
 
Hugo

I cant see this working as you describe it. My understanding is it senses if it is clipped onto the carabiner .... but surely this is the same as a current kill cord - the carabiner will be attached to the line and just dangle there but as it is attached will not sound the alarm.

Surely the way to do this is does the line have a decent tension on it from any source - shorts, leg and so on ( not that i have ever seen a leg used).

So this seems warm ( keep the original idea of a chord) but cold in that the main use case that works ( leg) would not seem widely used and carabiner sensing just gets you back to square one as it will just be left plugged in.

Also please bear in mind that in the med cords are nearly always clipped to swimwear not lifejackets - which are not in habitual use for short flat sea trips. The "if you must" comment suggests you consider this the exception, but in my experience it is the norm.

If this works I will be the first to buy one .. I think the idea is sound .. it just seems to be sensing the "wrong" thing. Chord extension would be moderately fool proof unless someone attached it a long way away to shut it up ... but then you would probably trip over it!
 
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I have not read the article.
If the alarm was triggered by lack of sense of ,a or a group of biometrics - then the cord has to be attached to a person ( presume helm )
Biometrics could be a simple pulse oximetry- a strap / Velcro that’s detects blood gasses saturation .
Or muscle electro activity. Skin temp , skin perspiration resistance or others ?
Or all or any of the above .Just has to recognise it’s a human .

This Velcro strap is attached to the kill cord , so if it’s not sensing a person - - it alarms .

With a clip n tension ( lack of biometrics) it could be attached to a life jacket ,but the jacket not actually worn , just chucked on the floor etc .
Hope this helps
 
No, it only switches off the alarm when the lifejacket key is inserted into the Lifecord clasp.

You leave this lifejacket key permanently attached to your lifejacket, shorts etc using the carabiner then slide the key in and out of the Lifecord clasp when you join or leave the helm.

The reason for having this special lifejacket key is because in tests it was impossible to keep sufficient tension on the line when it's simply hanging off a lifejacket or belt loop.

The 'normal' key, which stays permanently attached to the Lifecord, does have to have tension on the line in order for it to switch off the alarm. This tension is produced as soon as you wrap it round something reasonably substantial like a leg, arm, wrist, waist etc.

Hopefully this will become clear when you read next month's article and see the production ready Lifecord and the two different types of key.
 
So other than wrapping it round the mystery leg you need to have a special key plugged in to silence the alarm. You of course know what will happen ... people will just plug in the Key. Just as now. Not plugged in Boat won’t start. So people plug in and dangle.

This is so close to solving the problem but so far.

Detecting tension ( extension beyond the fully coiled resting state should not be that tricky. You are in effect saying is the end of the wire ( it is now electric wire ) close to the start of the wire. ( proximity sensor ). If yes it is probably not in use. If no they are sufficiently spectated that it probably is in use. No special catches, no magnets no nothing. Simply is one end far enough away from the other.

Just my 2 cents. Never expect a user to do something. They won’t ...
 
I always wrap the cord round my leg when using my Arrowflyte. Most people I know do so also.

I think it's quite standard in 'Speedboats' as the driver sits in a bucket seat with their legs out straight and the control down low next to the leg. I have to replace my cord every few years as it gets stretched from being wrapped round various legs.

RIBs, centre console etc. may be different but I have little experience of them.
 
Actually, the kill cord switch on the Novurania 4.3 is located next to your right leg so it is dead easy to clip round the leg.
The great thing with this is that your arms are free to operate the throttle and wheel.
Installations like this mean the the kill cord is much more likely to be used.
 
Why don’t engine manufacturers just use the same proximity sensor that we all have in our cars, set so engine needs sender to be within, say, 3m of receiver?

Keep the ‘key’ in your pocket. Get flung out; engine stops. OK, you’ve just lost £300 worth of key. Small price to pay, if the real problem is persuading people who naturally believe it won’t happen to them to make a positive decision to fit a cord to themselves.

Would need a manual override to get the engine going again when the key had gone glug, glug. But that’s easy enough.
 
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In the tender, I usually clip it to my shorts, rather than wrapping it around anything.
Sensing any tension in the cord must be possible.
 
Why don’t engine manufacturers just use the same proximity sensor that we all have in our cars, set so engine needs sender to be within, say, 3m of receiver?

Keep the ‘key’ in your pocket. Get flung out; engine stops. OK, you’ve just lost £300 worth of key. Small price to pay, if the real problem is persuading people who naturally believe it won’t happen to them to make a positive decision to fit a cord to themselves.

Would need a manual override to get the engine going again when the key had gone glug, glug. But that’s easy enough.

I guess the kind of person who doesn't habitually use a kill cord is probably the kind of person who will get on, fling the fob thing into a cup holder or where ever and set off. Or they'll leave it in their jeans pocket when they put their shorts or trunks on. And what about the previously discussed bikini wearer? Plus, as you say, if you go in with it and wreck it, or accidentally drop or lose it, you've got an immobile boat. Yes, you could keep a spare on board (for, as you mention, an extra £300) but if it's anywhere near the helm (unavoidable on a small boat - you mention a 3m range, so on a six metre boat or less it will be in range) then won't that just keep the engine running as the receiver will sense its proximity?
 
I guess the kind of person who doesn't habitually use a kill cord is probably the kind of person who will get on, fling the fob thing into a cup holder or where ever and set off. Or they'll leave it in their jeans pocket when they put their shorts or trunks on. And what about the previously discussed bikini wearer? Plus, as you say, if you go in with it and wreck it, or accidentally drop or lose it, you've got an immobile boat. Yes, you could keep a spare on board (for, as you mention, an extra £300) but if it's anywhere near the helm (unavoidable on a small boat - you mention a 3m range, so on a six metre boat or less it will be in range) then won't that just keep the engine running as the receiver will sense its proximity?
Yup, reckon the cup holder thing is the insurmountable bit. Even in the car I tend to sling the sender in a cubby, rather than keep it in my pocket. Back to the drawing board...
 
Can I just say bravo to MBY and partner for working on a better solution to this problem! I read the article and look forward to buying a couple. Having previously clipped cords onto shorts and life jackets I am happy to change if it means that I or my kids always remember to put on this life-saving device. I am certain that with time the. Lifecord will evolve as all products do into something increasingly refined and it is great to hear that you are alsready solving the lifejacket conundrum. Thanks guys!
 
Yup, reckon the cup holder thing is the insurmountable bit. Even in the car I tend to sling the sender in a cubby, rather than keep it in my pocket. Back to the drawing board...

My previous boat was a 6.5m RIB with jockey seats (tended to be standing when at helm). I made every attempt to be a good helm and always wear the kill cord wrapped around my leg, but once whilst heading out single-handed I noticed i had forgotten to re-attach the cord after casting off. I noticed pretty quickly (a couple of hundred metres out) based on a sense that something wasn't quite right (i'm fairly OCD at having everything in the same place so tend to get a feeling that something is missing).

A device that would give some kind of audible warning would have been great as an assistance device for those trying to do the right thing.

My worry is that if we try to make it too sophisticated it might become less reliable and become more of an annoyance to those who are trying to do the right thing (i'm wearing the cord but it's still bleeping at me, arrgh), and might end up nudging the "good guys" into bad habits to shut things up.

Having said that, one of my other hobbies is railways. On the railways they didn't so much have a problem of the driver being thrown from the cab, but do have theoretical problems of the driver being incapacitated so they tend to have a "dead mans switch" (commonly a foot pedal) that would apply the brakes (in boating world cut the engine) if no longer depressed. For boating (single-handed where you might have to leave the helm to deal with lines, or you might get bounced about in chop and hard to keep foot on it) you could perhaps give a grace period of Xseconds before the engine is cut (it could also perhaps be something gripped by the hand e.g. on the steering wheel or throttle if you're worried about keeping foot on a pedal in the chop)

In the train world i think they had problems with some lazy drivers just sticking something heavy on it to keep it depressed at all times, i'm not sure you'll be able to save everyone without it getting too complicated (full AI image processing looking for someone on board)
 
My previous boat was a 6.5m RIB with jockey seats (tended to be standing when at helm). I made every attempt to be a good helm and always wear the kill cord wrapped around my leg, but once whilst heading out single-handed I noticed i had forgotten to re-attach the cord after casting off. I noticed pretty quickly (a couple of hundred metres out) based on a sense that something wasn't quite right (i'm fairly OCD at having everything in the same place so tend to get a feeling that something is missing).

A device that would give some kind of audible warning would have been great as an assistance device for those trying to do the right thing.

My worry is that if we try to make it too sophisticated it might become less reliable and become more of an annoyance to those who are trying to do the right thing (i'm wearing the cord but it's still bleeping at me, arrgh), and might end up nudging the "good guys" into bad habits to shut things up.

Having said that, one of my other hobbies is railways. On the railways they didn't so much have a problem of the driver being thrown from the cab, but do have theoretical problems of the driver being incapacitated so they tend to have a "dead mans switch" (commonly a foot pedal) that would apply the brakes (in boating world cut the engine) if no longer depressed. For boating (single-handed where you might have to leave the helm to deal with lines, or you might get bounced about in chop and hard to keep foot on it) you could perhaps give a grace period of Xseconds before the engine is cut (it could also perhaps be something gripped by the hand e.g. on the steering wheel or throttle if you're worried about keeping foot on a pedal in the chop)

In the train world i think they had problems with some lazy drivers just sticking something heavy on it to keep it depressed at all times, i'm not sure you'll be able to save everyone without it getting too complicated (full AI image processing looking for someone on board)

sorry for replying to myself: a guess a simpler solution rather than sticking something extra to pull on the throttle is just to have the throttles spring-loaded to return to neutral unless active pressure is applied.
 
Surely the answer (for the forgetful, not the ones who don't care) is get into the habit of having the kill cord attached to you first and never ever to the engine first. I tend to attach the kill cord to my wrist well before even getting into the rib and it's still attached when I get out. So as an extension of me, the engine just won't start unless I attach it - which has happened more than once.
 
Surely the answer (for the forgetful, not the ones who don't care) is get into the habit of having the kill cord attached to you first and never ever to the engine first. I tend to attach the kill cord to my wrist well before even getting into the rib and it's still attached when I get out. So as an extension of me, the engine just won't start unless I attach it - which has happened more than once.

that's brilliant and so simple...! especially if you tend to clip to belt loop/lifejacket/wrist/bikini rather than round your leg. I will be employing that method from now on. Thanks!
 
Surely the answer (for the forgetful, not the ones who don't care) is get into the habit of having the kill cord attached to you first and never ever to the engine first. I tend to attach the kill cord to my wrist well before even getting into the rib and it's still attached when I get out. So as an extension of me, the engine just won't start unless I attach it - which has happened more than once.

Fantastic idea! Make the cord part of your clothing, rather than part of the boat.
 
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