© 1999 Robert A. Freitas Jr. All Rights Reserved.

Robert A. Freitas Jr., Nanomedicine, Volume I: Basic Capabilities, Landes Bioscience, Georgetown, TX, 1999

4.9.2 Proprioceptive Macrosensing

4.9.2.1 Kinesthetic Macrosensing

Using a navigational transponder network (Section 8.3.3), a population of ~10¹¹ nanodevices each spaced an average ~100 microns apart throughout the body tissues can determine relative location to a positional accuracy of ~3 microns and an angular accuracy of ~2 milliradian, with the data updatable once every millisecond. Thus dispersed, the network can continuously monitor and record the relative positions of all limbs with worst-case (cumulative error) ~0.8 mm accuracy over a 2-meter span (Section 8.3.3). These devices can prepare high-resolution dynamic maps of body position, velocity, acceleration and rotation, allowing precise real-time digital kinesthesia during sports or artistic activities such as gymnastics, pole vaulting, or ballet; during transportative activities such as driving cars around hairpin turns, roller-coaster rides, military aircraft maneuvers and space launches; during precision tool-using such as needle-threading, antique watch repair, or while using the fingers as measurement calipers; during self-defense activities requiring complex motions such as karate or judo; and during emergency situations such as automobile crashes and tumbling motions during falls from great heights. All such sensory data is readily outmessaged to the patient or user in real time (Section 7.4).

Nanorobots could assist in path integration or the reconstruction of experienced limb trajectories.¹⁰⁴⁰ Given the ability to determine rotation rates and to measure applied forces and torques, the network should also be able to forecast the anticipated future positions of limbs. By comparing these projections to actual results, the network can then infer the viscosity of the medium in which the activity is taking place (e.g., air or water), whether the environment is stable or is translating or rotating in some direction, and whether the human user is physically supported or in free-fall. Internal nanodevices can directly measure if a body is sitting, standing, laying prone, inverted, falling, floating or diving, and then communicate that information directly to the human user (Section 7.4). Detection of patient activity states -- e.g., the patient is sitting, standing, or walking -- can be used to control nanorobot behaviors (Chapter 12), activate or deactivate outmessaging displays (Section 7.4.6), and so forth. A simple macroscale wearable tactile "compass belt" that would convey desired geographical directions has already been proposed.²⁹⁹⁴

Last updated on 17 February 2003