This has potential. I'm thinking that what's required is a set of probes actuated by a common pneumatic system, each driving a spring of calibrated constant so that when pneumatic pressure is removed, they'd clear the human tissue. There are a few "issues" however. First of all, with a pneumatic system, the pressure would be the same at the driven end of the probe. However, the restoring spring has to be capable of pushing the probe to a position at which it clears the human tissue. That means there's to be an offset nulling procedure that has to be performed on each probe before the process proceeds, and it has to be very reliable, as it could cause physical damage if the process breaks down. Further, if the pressure is the same at each probe's driven end, how does one take deflection measurements, which are required to determine relative tissue resistance?

There's still conceptual work to be done on this, but I do like the equal pressure aspect of a pneumatic system. I like the spring-driven probe, too, as that provides some isolation and mitigates the risk of tissue damage.

RE