Solution to measure mining drill hole depth with some water slurry at bottom of hole

No chance with GPS in a drill hole, and even less chance  if it is partially filled with water. And equally low chance with radio or laser under those conditions. Your best bet is measuring the length of the drilling shaft mechanically.

Hi Trux thanks for this. We can get the GPS from the Drill and correspond that to the actual drill hole if need be. What we really need asap is to be able to measure the drilled hole depth. Yes we already know the dril bit length etc and the depth the drill bit drilled to. However, the reason why we need the hole depth measured after the drill bit has pulled out is because there are a lot of drill hole cave-ins where by, either the soil type just caves in at some sections of the drill hole due to that soil type or caves-in mainly down the lower part of the drill hole due to the drill bit pulling out. This causes soil cave-in and we need to know how much it has caved-in, so we can make an informed on the spot decision to either re-drill the hole because it has caved in more than the desired amount or move to next hole to drill. Let me know if anyone has any ideas on the best way to achieve this even if it requires one, two or three or more technologies to measure to the bottom of hole and through water and if we can measure the water level as well that would be an additional bonus but not critical. just hole depth measured from top of hole to bottom of hole soil level and should be able to accurately measure through water that has seeped in as well. thank you

7752338 said:

We can get the GPS from the Drill and correspond that to the actual drill hole if need be.

You can perhaps get the GPS coordinates at the top of the drill hole, but there is no chance to get any usable GPS signal from a drill hole several meters deep, and the EM waves do not propagate through water, so EM waves cannot be used to measure the depth under the water surface. Besides that, the vertical accuracy of GPS is miserable even under excellent GPS signal conditions.

The only common technology (apart from a mechanical tool) that could "perhaps" work, is ultrasound, though it would be challenging anyway. 

Anyway, this is not something that could be developed with the Connect IQ technology on a Garmin watch. I rather recommend contacting manufacturers specialized in mining and geoindustry equipment.

The only way you could measure the depth of the drill hole using a Garmin watch, would be by using one of the Garmin Descent (MK1, MK2, MK3 or G1) diving models, suspended on a rope together with a weight, and slowly sunk to the bottom of the hole. The watch would then record the depth till the surface with the barometric altimeter, and then the depth of the water column with the depthmeter. However, it is questionable whether the accuracy and the reliability of the barometric altimeter would be sufficient for your purpose. 

7752338 said:

Hi I am looking for initial technology advise and potentially developers/engineers to design and manufacture a prototype etc.

This is way out of scope for this subforum (or any other subforum here).

This subforum is about writing software for devices.

(In any case. you aren't going to get any sort of GPS reception in a deep hole.)

trux said:

The only way you could measure the depth of the drill hole using a Garmin watch, would be by using one of the Garmin Descent (MK1, MK2, MK3 or G1) diving models, suspended on a rope together with a weight, and slowly sunk to the bottom of the hole.

You don't need the watch. Just measure how much "rope" is let out. 

dpawlyk said:

You don't need the watch. Just measure how much "rope" is let out

That's what I suggested in my first post - measuring the depth by measuring the length of the drilling shaft  And as well in my second post, telling that measuring it mechanically is the simplest solution. For some strange reason 7752338 insisted on using Garmin for measuring the depth, hence the proposal. If it really has to be done with Garmin (with our without Connect IQ), then the solution I proposed is the only one I can imagine.

ok understood thank you. Yes they are currently measured by hand with a special built tape measure but only after the fact once the drill has left the immediate area and its safe for workers to enter the area and start to measure all of the holes by hand. We really need to measure from the top of the hole without any human intervention manually getting out of the drill cabin due to safety and operational issues. Also, by measuring automatically and digitally after the drill has pulled out of hole but drill still in position, then the drill operator can make a decision to either re-drill the hole due to soil cave in when the drill bit was retracted or move to next new hole to drill. We need almost instant ( hopefully within 5 +/- mins) drill hole depth information so the operator can make quick informed decisions. thank you for your input to date its muchly appreciated. Do you think that any other section of Garmin could help with this requirement using another of their technologies available?

I suspect this application is not within anything Garmin is doing. Garmin does have depth finders but the may need to be submerged and in an open area.

I doubt anybody in these forums would be able to do much for you.

Seems like you want magic.

If there was no water you could use a barometric sensor.  I use this in one of my watchface apps to measure the height of a building for example.  It sounds like you need something like a magnetometer which works by measuring the force of gravity.  See https://scintrexltd.com/  ( I don't work for this company nor do I have any interest in it other than knowing of it)