Depends. If line tracking is an option, there are several simple and reliable options.

When regarding track-free operation, you may consider camera-based triangulation plus 3D-modelling of the environment.

Regarding wireless triangulation, it will be difficult to achieve the precision targeted: everything depends on the accuracy of the measurement of angles or signals - both difficult to implement with respect to a position accuracy of 10 cm.

Regards

NFC is your solution. Tags are cheap... many new phones come with NFC readers....you just need an app to link the particular tag with the position.

You can check the article :

Zhenghua Chen," Smartphone Inertial Sensor Based Indoor Localization and Tracking with iBeacon Corrections", IEEE Transactions on Industrial Informatics (Volume:PP , Issue: 99 ), DOI: 10.1109/TII.2016.2579265, 09 June 2016

You can take the concept for prototyping.

Thank you, Best wishes.

WiFi & Bluetooth-low-energy (BLE) beacons fingerprinting and/or image feature tracking plus low-grade IMU, I guess. For the first I should refer you to Navigine guys (navigine.com) and their publications, for the second - to Prof. Trommer's (KIT) UAV guidance reseach. He has many studies in the field with his team, but the one I've seen recently was on ICINS 2016 this May in Saint-Petersburg, Russia. As far as I know those two are among leaders in indoor positioning.

Hello Pierre,

You can look for some optical (Visible / IR / Laser) based industrial photoelectric proximity sensors that come in variety of output options and power supplies and a wide range of sensing range from few mm to several meters. You can look for industrial suppliers such as RS or Farnell in your country to meet your specifications and price range.

Best Luck!

-Prasanna Waichal