Distance Measurement - between 6 points, individually moving in (almost) any direction within 1m I'm trying to find a solution for a given task in a problem I want to solve.
Assume I have 6 individual Points in a 3D environment of about 1m³. Each point will be able to change position (almost) freely.
Is there a way I can get the information of which distance each point is to any of the remaining 5 points?
Background Idea for understanding: Say its 2 wooden triangles (one of those points on each angle) and I need to calculate how far and in which direction one is moving from or towards the other. 
By comparing all those distances, direction and step-width may be easily calculated.
Are there like "coded" distance-sensors so they don't mix their signals?
Any thoughts highly appreciated.
You may try to implement some kind of ultrasonic transponders. The
emitter sends a code addressing a specific receiver. Upon recognizing
its address, the receiver replies after a short, fixed delay. The
emitter measures the time it took the response to reach it, and from
there computes the distance.

You may need some kind of omnidirectional transducers (e.g. this
models) if you want the measurement to work in any
direction. And also a protocol to avoid several emitters talking at the
same time.

This seems to me like a very complex project though.