I have had some reall good advice on similar questions here and I have one more.
I am looking for a device that can measure tapers. In other words suppose I have a 2 ft long board that has a 1/2" thickness taper and a 1/4" width taper. Does a device exist that I could simply slide down the board in one motion and it would record and print out incremental width and thickness readings?This question relates to an archery bow testing station we are trying to put together. The success of the testing station is largely dependent on its ability to gather data quickly and accurately. Many of these tests would be performed at some of the larger archery gatherings where we would be testing the bows of the particapants.
You can get calipers with serial data outputs. You would still need to take discrete readings, although you could automate the process if you wanted to spend enough money.
I am becomming more and more open minded as I get into this profect about investing more into it. It is a not for profit bow test station but the more folks I talk to about this the more it seems to be taking on a life of its own. I feel pretty confident that several archery shops and manufacturers would partner up on this once I establish a firm blue print and how it will operate.
We are talking now about creating an online data base that the station would feed into that could be referenced by either anyone or whoever was allowed to reference it. Speed of testing and measuring is the whole key. A complete an analysis in about 5 min is the goal.
To do this would require an automated testing station.
You could build one with a single-axis drive, a data-logging caliper, and some software.
You might be able to do this optically, too (use a video camera to measure the width, as the camera pans down the length of the bow).
I don’t think you will find anything that will do exactly what you want off-the-shelf, but there are lots of companies that can help you make this device.
For example.
Couldn’t you do this with just a good optical scanner?
ETA: And some software
They would be the ones to know, I sent them an email
I really don’t know much about precision high tec measuring but a few others have suggested optical as well.
freaking laser beams
I don’t remember if this was mentioned in any prior thread, but you might want to look into some of the mechanical modeling software. I’ve never used it and it’s been a few years, but I recall one engineering department that modeled high-strength robotic components and applied Fourier analysis and other tests to determine weak points. There may well be a low-cost or even free tool with those capabilities now, and you could model various bow shapes and sections with arbitarily-defined material specs, and at least whittle down the number of full-scale prototypes needed.
Knowing things like this are out there now are exciting. I will look into it as well.
We all know what you’re really doing. 
There are laser measuring programs that provide input into CAD programs. They can generate very precise drawings of a 3d space.
ETemplate is one example. heres a 2 part demo. I’m sure there are other similar products.
This technology can be modified for various purposes. Countertops are measured with a simplified version of this tech. They can measure multiple points along the way and custom cut a countertop. Lowes and Home Depot measure custom countertops this way.
Couldn’t you just have two measuring sticks on the fixed surface that are 2 ’ (or your standard) apart…
So then the test subject is placed down on that, and the measurement of the change in width (or thickness ) is measured. You could have a table (a sheet of paper) that converts that change to angle or ratio or inches per foot or mm per metre or other unit for taper,
A portable CMM w/ sapphire stylus would do exactly what you want. More accurate than laser scanning, too. We have one at work, and it’s pretty awesome.
Not cheap, though.
For a low-cost solution, how about a spring loaded outside thickness gage, like this?
Some luthiers use something called the Mag-ic Probe to measure the thickness of wood. I think it’s based on the Hall Effect principle.
One manufacturer of a commercial Hall Effect thickness gage claims to be able to measure the thickness of wood up to 1 inch thick.
Those were some very interesting solutions, well within the budget also. Good suggestion.
That really is awesome, out of curiosity I am going to check out the price tag.