How can I measure dimensions of square, pentagonal or hexagonal blank w/Arduino?

Hello. I’m new on this forum and I would like to use Arduino for a project and I need some advice on whether this is a possible application and what sensors, etc I could use for this.
I would like to measure tapered bamboo blanks made for flyfishing rods, using a measuring sensor system.
I need to check the blank dimensions along its lenght and centesimal precision (metrical) is required. For square (quad) and exagonal rods I use a caliper or a micrometer to check dimensions between the opposite sides of the bamboo blank. I can’t do the same for a pentagonal rod blank, taking the measure between one side and the opposite vertex of the regular pentagon section. This is the reason why I’m thinking about a laser sensor system or something like that.
The dimensions may vary from 15.0mm to 1.0mm and usually the taper is checked every 12.7mm (5"inches) on the blank lenght.
I attached a couple of photos of the blanks as samples.

Thank you in advance.

11.jpg

I can't do the same for a pentagonal rod blank, taking the measure between one side and the opposite vertex of the regular pentagon section.

Why not? It will give you a measurement and assuming a regular pentagon you can calculate any other dimension from the one measurement.

This is the reason why I'm thinking about a laser sensor system or something like that.

A laser measuring system only measures distance to not distance through or across. It looks like you will still have to use some sort of caliper system to measure your rods at any point other than at the ends.

Maybe some sort of roller system that moves an arm attached to a caliper will enable you to get a profile graph of the whole rod. I think your problem is going to be mainly mechanical.

look at https://hackaday.io/project/511-digital-dial-indicator-cnc-surface-probe

regards

Allan

Thanks for your answers. It isn't easy to take the height of a regular pentagon between a side and the opposite vertex, especially when this size is a little more than 1 millimeter and centesimal precision is required. I've seen that Keyence makes measurament sensors, optical and laser micrometers for industrial applications, and I would like to know if someone has already done something similar using Arduino. You can check the Keyence products at http://www.keyence.com/products/measure/index.jsp