Perhaps there are non-contact ranging sensors you can use to try to determine the depth of the water by mounting them immediately before each tire. You could set up one sensor to determine the distance between the chassis of the automobile and the ground. The second sensor can be used to determine the distance between the chassis and the surface of the water. This, of course, would be dependent on whether or not such sensors exist, and if so, whether or not it could be calibrated to detect the surface of the water accurately.
Continuing on with my brainstorming, perhaps you could develop a sensor that will float or skip across the surface of the water immediately before the tire. The sensor could be mounted on a trailing-arm type apparatus, and can move
up and down as the height of the surface of the water changes with respect to the chassis (like a waterski on the surface of the water). But you'll likely need to also measure the distance to the ground so that you can remove variation of the suspension height to get the actual depth of the water, especially as you go over bumps or irregularity in the road (assuming non-ideal conditions). Perhaps you could also get that data by measuring the location of the axles relative to the chassis, which could also provide information on how far the chassis is from the ground.
You could also contact an NI alliance partner to see if they have application ideas on measuring the depth of the water. http://www.ni.com/alliance
Hope this gives you some ideas!
Regards,
Wilbur Shen
Applications Engineer
National Instruments
P.S. The Measure category is for the software product called Measure from NI, so your post would actually be more accurately posted in the "Sensors" category.
