A system for guiding a piece of apparatus into relationship with another piece of apparatus, comprising:
- robotic means for guiding a device into position relative to an object;
- means for controlling said robotic means;
- a device attached to said robotic means and including at least one capaciflector type proximity sensor affixed thereto for sensing an object coming into relatively close proximity therewith;
- said capaciflector type proximity sensor including,
- at least one outer electrical conductor on a surface of said device and forming one electrode of a sensor capacitor, the other electrode of said sensor capacitor comprising said object,
- an intermediate electrical conductor located between said at least one outer conductor and said surface and being of a size larger than said at least one outer conductor to act as a shield for reducing the parasitic capacitance between said outer conductor and said surface,
- said intermediate conductor and said outer conductor mutually overlaying each other,
- said at least one outer conductor and said intermediate conductor further being located on said surface with no air gap therebetween and no air gap between said intermediate conductor and said surface, and wherein said surface acts as a surface of reference potential or a ground plane;
- an AC voltage source;
- and
- circuit means coupled between said AC voltage source and said at least one outer and intermediate conductors for coupling a same voltage from said voltage source to said outer electrical conductor and said intermediate electrical conductor, said circuit means being responsive to the change in capacitance of said sensor for generating an output signal, said output signal being coupled to said means for controlling said robotic means, and
- wherein said means for controlling generates control signals for controlling said robotic means to move said device in an operational mode whereby said robotic means guides said device to a predetermined location on said object and moves said device in a predetermined scan pattern over said location, whereby since electrical charge slides along the surface of a conductor the charge thereat induces an equal but opposite charge on an opposing member these charges collect at the point nearest each other, thereby referencing each other without any offset, and by a process of signal minimization of said output signals which are generated in response to a capacitance verses distance characteristic of said sensor, said device is moved in ever decreasing translational increments by said robotic means into position for making contact with said object without any prior undesired contact or collision therewith.