anchor chain/rope measure

[skipperearly]

I am aware of the usual method to make marks on the anchor chain or -rope to indicate the length let out. Various color codes have been suggested - however they all require someone going to the bow and check the marks.
Have also seen the e-winch counters with cables led to the cockpit to show readings.

However, what I was looking for is a way, to mount a sort of sensor or tag to the anchor and then measure the distance by e.g sonar signal which then can be shown in some app on the Raspi or handphone.

Has anyone played around this ideas or any experiences/comments?

[ranger58sb]

Our rode counter works by way of a single magnet mounted on the drum so it can "sensed" at each full rotation. Essentially the same way our tachometers work...


Perhaps there's a way to sense that, wirelessly?


-Chris

[Hydra]

skipperearly,
I think your idea consists of measuring the distance between the anchor and the boat, not the length of rode. In the first steps of anchoring, before setting the anchor, the chain is often not straight at all: the rode is much longer than the distance to the anchor.

Alain

[RaymondR]

Interesting idea. Oil drillers used to use pingers on the bottom to position their drilling rigs. When they no longer needed them a signal was sent to the pinger which caused it to release from the anchor weight and float to the surface to be recovered.


If you had forward looking sonar and a pinger on the anchor it might show a bright return, but since the signal path is halved you would have to double the distance shown.


I never bother with chain out measurements, I just go hard astern until I either run out of chain or the anchor holds properly then put out five more metres.