Position responsive apparatus, system and method having electrographic application

In a system wherein a position responsive surface is selectively accessed to develop electrical signals which are treated to provide outputs corresponding with the accessed position and wherein said surface is configured having an insulative support, a first array of elongate, thin parallel mutually spaced grid elements located from first to last upon said support a second array of elongate, thin parallel mutually spaced grid elements located from first to last upon said support spaced from said first array of grid elements and angularly oriented with respect thereto, first resistor means coupled at node positions with adjacently disposed grid elements of said first array for providing discrete resistances between said node positions, and second resistor means coupled at node positions with adjacently disposed grid elements of said second array for providing discrete resistances therebetween, the method of correcting the value of given said outputs, comprising:

• providing a memory for retaining computed physical domain coordinate values derived from values corresponding with select outputs of a signal domain established for each said node position of said first and second resistor means, adjusted in correspondence with a regularly incremented sequence of address values within said signal domain;
• deriving a said address value from a said given output;
• accessing said memory at said address value to provide a computed physical domain coordinate value by interpolative weighting thereof in correspondence with said given output to derive a corrected said given output;
• and
• outputting said corrected given output to provide coordinate information representing said accessed position at said surface.

The method for generating a memory retained look-up table for use in interpolatively correcting the position outputs in a signal domain corresponding to accessed locations within the signal domain of a position responsive surface of a type including an insulative support, a first array of elongate, thin parallel mutually spaced grid elements located from first to last upon said support a second array of elongate, thin parallel mutually spaced grid elements located from first to last upon said support spaced from said first array of grid elements and angularly oriented with respect thereto, first resistor means coupled at node positionswith adjacently disposed grid elements of said first array for providing discrete resistances therebetween, and second resistor means coupled at node positions with adjacently disposed grid elements of said second array for providing discrete resistances therebetween, comprising the steps of:

• collecting an input data set from said surface as signal domain outputs established by said discrete resisitances at the said physical domain node positions for said first and second resistor means;
• determining the bounds of said input data set as maximum and minimum signal domain values for first and second coordinate directions corresponding, respectively, with said first and second resistor means;
• deriving first and second sets of regularly incremented address locatable values extending between said maximum and minimum signal domain values corresponding, respectively, with said first and second coordinate directions;
• deriving by linear interpolation the physical domain coordinate location value on said surface corresponding with said address locatable values for each said first and second coordinate directions;
• and
• positioning said interpolated physical domain coordinate location values in said memory in combination with corresponding said signal domain address locatable values.

Position responsive apparatus, comprising:

• an insulative support;
• an x-coordinate array of elongate, transparent grid elements extending between first and second borders and located in mutually spaced parallel relationship from first to last upon said support means;
• a y-coordinate array of elongate, transparent grid elements extending between third and fourth borders spaced from said x-coordinate array of grid elements and located in mutually spaced parallel relationship from first to last upon said support means;
• first x-coordinate resistor means coupled at said first border with adjacently disposed grid elements of said x-coordinate array for providing discrete resistance therebetween;
• second x-coordinate resistor means coupled at said second border with adjacently disposed grid elements of said x-coordinte grid array for providing discrete resistances therebetween;
• x-coordinate terminal means coupled with said first and second x-coordinate resistor means adjacent said first and last grid elements for conveying excitation signals thereto;
• first y-coordinate resistor means coupled at said third border with adjacently disposed grid elements of said y-coordinate array for providing discrete resistances therebetween;
• second y-coordinate resistor means coupled at said fourth border with adjacently disposed grid elements of said y-coordinate grid array for providing discrete resistances therebetween;
• y-coordinate terminal means coupled with said first and second y-coordinate resistor means adjacent said first and last grid elements for conveying said excitation signals thereto;
• a time varying excitation source of select frequency;
• switching means controllable for selectively applying an excitation signal corresponding to said source to said x-coordinate terminal means during a first operational mode and for selectively applying said excitation signal to said y-coordinate terminal means during a second operational mode;
• locator means movable in adjacency about said support for select interaction with said x-coordinate and y-coordinate arrays of said grid elements during said first and second modes to effect the derivation of position signals;
• detector circuit means responsive to said position signals for deriving digital position signals;
• and
• control means for controlling said switching means and treating said digital position signals to derive coordinate pair output signals with respect thereto.

Position responsive apparatus comprising:

• a first array of parallel, spaced grid elements arranged in a sequence from first to last and located for nearest operational adjacency with a locator accessible working surface for developing first coordinate position information;
• a second array of parallel, spaced grid elements arranged in a sequence from first to last for developing second coordinate position information, spaced a predetermined distance from said first array and angularly disposed with respect thereto to establish cross-over locations of mutually spaced elements respectively within said first and second arrays;
• insulative means intermediate said first and second arrays for effecting said spacing therebetween;
• said grid elements within said first array having a first width within said cross-over locations and a second width outwardly thereof greater than said first width;
• said grid elements within said second array having a third width within said cross-over locations and a fourth width outwardly thereof greater than said third width;
• first resistor means coupled with adjacently disposed grid elements of said first array for providing discrete resistances therebetween;
• second resistor means coupled with adjacently disposed grid elements of said second array for providing discrete resistances therebetween;
• first terminal means coupled with said first resistor means in the vicinity of said first and last grid elements thereof;
• second terminal means coupled with said second resistor means in the vicinity of said first and last grid elements thereof;
• a time varying excitation source of select frequency;
• switching means controllable for selectively applying an excitation signal corresponding to said source to said first terminal means during a first operational mode to establish a potential gradient along said first resistor means, and for selectively applying an excitation signal corresponding to said source to said second terminal means during a second operational mode;
• and
• control means for controlling said switching means to derive said first and second operational modes.

Position responsive apparatus comprising:

• a first array of parallel, spaced grid elements arranged in a sequence from first to last and located for nearest operational adjacency with a locator accessible working surface for developing first coordinate position information;
• a second array of parallel, spaced grid elements arranged in a sequence from first to last for developing second coordinate position information, spaced a predetermined distance from said first array and angularly disposed with respect thereto to establish cross-over locations of mutually spaced elements respectively within said first and second arrays;
• insulative means intermediate said first and second arrays for effecting said spacing therebetween;
• said grid elements within said first array having a first width in the vicinity of said cross-over locations and a second width outwardly thereof greater than said first width;
• said grid elements within said second array having a third width in the vicinity of said cross-over locations and a fourth width outwardly thereof greater than said third width;
• first resistor means coupled with adjacently disposed grid elements of said first array for providing discrete resistances therebetween;
• second resistor means coupled with adjacently disposed grid elements of said second array for providing discrete resistances therebetween;
• first terminal means coupled with said first resistor means in the vicinity of said first and last grid elements thereof;
• second terminal means coupled with said second resistor means in the vicinity of said first and last grid elements thereof;
• third terminal means coupled with said first resistor means at at least one position intermediate said first terminal means;
• a time varying excitation source of select frequency;
• switching means controllable for selectively applying an excitation signal corresponding to said source to said first terminal means during a first operational mode to establish a potential gradient along said first resistor means, and for selectively applying an excitation signal corresponding to said source to said second terminal means simultaneously connecting said first terminal means and said third terminal means with effective ground during a second operational mode;
• and
• control means for controlling said switching means to derive said first and second operational modes.

Position responsive apparatus comprising:

• a first array of parallel spaced grid elements arranged in a sequence from first to last and located for nearest operational adjacency with a locator accessible working surface for developing first coordinate position information;
• a second array of parallel, spaced grid elements arranged in a sequence from first to last for developing second coordinate position information, spaced a predetermined distance from said first array and angularly disposed with respect thereto to establish cross-over locations of mutually spaced elements respectively within said first and second arrays;
• insulative means intermediate said first and second arrays for effecting said spacing therebetween;
• first resistor means coupled with adjacently disposed grid elements of said first array for providing discrete resistances therebetween;
• second resistor means coupled with said adjacently disposed grid elements of said second array for providing discrete resistances therebetween;
• first terminal means coupled with said first resistor means adjacent said first and last grid elements thereof;
• second terminal means coupled with said second resistor means adjacent said first and last grid elements thereof;
• third terminal means coupled with said first resistor means at at least one position intermediate said first terminal means;
• fourth terminal means coupled with said second resistor means at at least one position intermediate said second terminal means;
• a time varying excitation source of select frequency;
• switching means controllable for selectively applying an excitation signal corresponding to said source across said first terminal means and for simultaneously coupling said second and fourth terminal means with ground during a first operational mode, and for applying an excitation signal corresponding to said source across said second terminal means and for simultaneously coupling said first and third terminal means with ground during a second operational mode;
• and
• control means for controlling said switching means to derive said first and second operational modes.

Position responsive apparatus comprising:

• a first array of parallel, spaced grid elements arranged in a sequence from first to last and located for nearest operational adjacency with a locator accessible working surface for developing first coordinate position information;
• a second array of parallel, spaced grid elements arranged in a sequence from first to last for developing second coordinate position information, spaced a predetermined distance from said first array and angularly disposed with respect thereto to establish cross-over locations of mutually spaced elements respectively within said first and second arrays;
• insulative means intermediate said first and second arrays for effecting said spacing therebetween;
• first resistor means coupled with adjacently disposed grid elements of said first array for providing discrete resistances therebetween;
• second resistor means coupled with adjacently disposed grid elements of said second array for providing discrete resistances therebetween;
• first terminal means coupled with said first resistor means adjacent said first and last grid elements thereof;
• second terminal means coupled with said second resistor means adjacent said first and last grid elements thereof;
• third terminal means coupled with said first resistor means at a predetermined position intermediate said first terminal means;
• fourth terminal means coupled with said second resistor means at a predetermined position intermediate said second terminal means;
• a time varying excitation source of select frequency;
• switching means controllable for selectively applying an excitation signal corresponding to said source to said first terminal means to establish a first potential gradient along said first resistor means and simultaneously applying an excitation signal to said third terminal means corresponding to said source and attenuated substantially proportionately with respect to a select value of said first potential gradient for said predetermined position during a first operational mode, and for appying an excitation signal corresponding to said source to said second terminal means to establish a second potential gradient along said second resistor means and simultaneously applying an excitation signal to said fourth terminal means corresponding to said source and attenuated substantially proportionately with respect to a select value of said second potential gradient for said predetermined position during a second operational mode;
• and
• control means for controlling said switching means to derive said first and second operational modes.

In a system wherein a position responsive surface is selectively accessed to develop electrical signals which are treated to provide outputs corresponding with the accessed position and wherein said surface is configured having an insulative support, a first array of elongate, thin parallel mutually spaced grid elements located from first to last upon said support, a second aray of elongate, thin parallel mutually spaced grid elements located from first to last upon said support spaced from said first array of grid elements and angularly oriented with respect thereto to establish a plurality of grid element cross-over regions, first resistor means coupled at node positions from first to last with adjacently disposed grid elements of said first array for providing discrete resistances between said node positions, and second resistor means coupled at node positions from first to last with adjacently disposed grid elements of said second array for providing discrete resistances therebetween, the method of deriving given said outputs, comprising:

• providing a time varying source of select frequency and an effective ground;
• exciting said first array during a first operational mode by applying said source to said first resistor means adjacent said first node while simultaneously applying said ground to said first resistor means adjacent said last node and subsequently alternating said application of source and ground;
• electrically coupling said second array to ground during said first operational mode by applying ground to said second resistor means adjacent said first and last nodes thereof and at at least one select location therebetween;
• exciting said second array during a second operational mode by applying said source to said second resistor means adjacent said first node while simultaneously applying said ground to said second resistor means adjacent said last node and subsequently alternating said application of source and ground;
• electrically coupling said first array to ground during said second operational mode by applying ground to said first resistor means adjacent said first and last nodes thereof and at at least one select location therebetween;
• accessing said surface with a signal responsive locator during said first and second operational modes to develop said electrical signals;
• and
• treating said electrical signals to provide coordinate information representing said accessed position at said surface.