I'd like to see a non-contact version of arm with a sorta stylus that reads the tracing with the accuracy of a disc drive
Hard drives like those found in personal computers do indeed have a read-write head that flies aerodynamically above the disk surface, kept there by the airflow as the disk spins. Would need to replace the magnetic field sensor with two distance sensors. I feel an R & D grant application coming on.
As an aside, in counries like Australia venture capital is like unobtanium so governments step in to fill the financing void!