How to measure ice thickness/growth

Hi everyone,

I'd like to bounce some ideas I had for measuring ice thickness or growth with my Arduino mega. I'm already using the mega for temperature measurements with 5 analog pins, and data logging with an sd module and an RTC.

I'd like to monitor ice thickness/growth in clear plastic cylinders with a sensor and I found the Adafruit VL53L0X Time of Flight Distance Sensor and was wondering if this is a good option or if there is something more suitable.
With this sensor I was thinking of measuring from the bottom of my cylinder, they are 7mm thick. The sensor would have to measure through a saline water column of about 40cm until reaching the bottom of the ice. I'm not sure this sensor is able to do this. I also have to keep in mind that as the ice grows thicker, it will expand in both directions so this approach might not be possible.

I'd also like to add that the water column will change color too due to microalgae in it.

The other idea I had was using a different sensor to measure from the top, like the ones used for measuring paint coat thickness, but I haven't found a good sensor yet.

Another idea was to use something like a light barrier to measure the growth but I again, haven't been able to find a fitting sensor.

I'd very much appreciate any comments or suggestions. Please be kind, I'm a biologist by training and learning as I go.

Thank you!

padmoo:
Hi everyone,

I'd like to bounce some ideas I had for measuring ice thickness or growth with my Arduino mega. I'm already using the mega for temperature measurements with 5 analog pins, and data logging with an sd module and an RTC.

I'd like to monitor ice thickness/growth in clear plastic cylinders with a sensor and I found the Adafruit VL53L0X Time of Flight Distance Sensor and was wondering if this is a good option or if there is something more suitable.
With this sensor I was thinking of measuring from the bottom of my cylinder, they are 7mm thick. The sensor would have to measure through a saline water column of about 40cm until reaching the bottom of the ice. I'm not sure this sensor is able to do this. I also have to keep in mind that as the ice grows thicker, it will expand in both directions so this approach might not be possible.

I'd also like to add that the water column will change color too due to microalgae in it.

The other idea I had was using a different sensor to measure from the top, like the ones used for measuring paint coat thickness, but I haven't found a good sensor yet.

Another idea was to use something like a light barrier to measure the growth but I again, haven't been able to find a fitting sensor.

I'd very much appreciate any comments or suggestions. Please be kind, I'm a biologist by training and learning as I go.

Thank you!

I think possibly measuring light transmission would do what you need. A light sensor and an RGB led. Imagine the led at the bottom of the cylinder and the sensor on top.

Simply measuring light transmission might tell you how much is ice and how much is water. It probably won't be linear, but you can certainly develop a calibration curve for it.

By measuring CHANGES in transmission of red, green and blue you could deduce the color changes and/or calibrate the liquid to solid ratio by adding the color change as a correction factor.

A plain LED as opposed to a collimated beam (i.e. laser) is probably better because liquid water will mostly pass the light while solid (ice) will scatter it. A laser would probably give you an "ice/no ice" indication, but no information as to HOW MUCH of each.

Not knowing enough details of your experiment, this is the best I can come up with.

The DS1603L ultrasound sensor may work.
It reads through the wall of your container; it's designed to bounce the waves off the water/air surface of the water so measures the water level from below. I expect the sound waves will also bounce off the water/ice surface, giving you the distance to the bottom of the ice.
Your container wall at 7 mm may be too thick for it; the 40 cm water is no problem.