Method and apparatus for determining centroid coordinates and angular orientation of a surface

Claim 2

Apparatus for determining the co-ordinates of the centroid of an area including: a. first means for electronically scanning said area in a substantially rectangular raster pattern with each line scan of said raster being at a predetermined respective frame voltage; b. second means for generating a line scan voltage which varies uniformly from a first fixed value at one end of each line scan to a second fixed value at the other end of each line scan; c. third means summing a voltage value proportional to each predetermined respective frame voltage for the duration of time the corresponding line is incident on the area to obtain a first final voltage representative of the average value of the frame voltage in the said area times the area itself;

Claim 3

d. fourth means for summing a voltage value for the respective portions of the line scan voltage for the duration of time the corresponding line scan is incident on said area to obtain a second final voltage representative of the line scan voltage in the said area times the area itself; e. fifth means for summing a voltage value proportional to the time durations of the incidence of the respective line scans on the area; f. sixth means for determining the particular time taken for said summed voltage quantities in accordance with (e) to decrease at a predetermined rate to a predetermined value; and, g. seventh means for causing said first and second final voltages to decrease at the same said predetermined rate for said particular time whereby the resultant voltage corresponding to said first final voltage is representative of one rectangular co-ordinate of said centroid in the plane containing said area and the resultant voltage corresponding to said second final voltage is representative of the second rectangular co-ordinate in said plane.

Claim 4

d. fourth means for summing a voltage value for the respective portions of the line scan voltage for the duration of time the corresponding line scan is incident on said area to obtain a second final voltage representative of the line scan voltage in the said area times the area itself; e. fifth means for summing a voltage value proportional to the time durations of the incidence of the respective line scans on the area; f. sixth means for determining the particular time taken for said summed voltage quantities in accordance with (e) to decrease at a predetermined rate to a predetermined value; and, g. seventh means for causing said first and second final voltages to decrease at the same said predetermined rate for said particular time whereby the resultant voltage corresponding to said first final voltage is representative of one rectangular co-ordinate of said centroid in the plane containing said area and the resultant voltage corresponding to said second final voltage is representative of the second rectangular co-ordinate in said plane.

Claim 5

Apparatus according to claim 1 wherein said means for scanning said area is a television camera having an electrostatic camera tube forming a part of the scanning system.

Claim 6

Apparatus according to claim 1 wherein said third, fourth, fifth, sixth and seventh means each includes means for converting the various voltages to digital equivalents, said digital equivalents being then summated to produce digital equivalents to the first and second summed voltage and thereafter processed in a digital manner.

Claim 7

Apparatus according to claim 1 wherein: a. said third means is a first storage means for accumulating each predetermined respective frame voltage for the duration of time the corresponding line scan is incident on said area; b. said fourth means provides a further storage for accumulating the voltage produced for the line scan to said area; c. said fifth means is a third storage means for accumulating a constant voltage through a fixed resistor for the duration of time each line scan is incident on said area so as to assume a final voltage representative of the area scanned; d. said sixth and seventh means providing an accumulative voltage in each storage means to leak away through resistors of equal resistive value until the voltage on said storage means of (c) reaches a specific said voltage value to terminate the process; e. first discharge means for discharging said first accumulating means through said first resistive means; f. second discharge means for discharging said second accumulating means through said third resistive means; g. third discharge means for discharging said third accumulating means through said third resistive means; and h. control means for controlling the discharge tine of said first and second storage means so as to be equal to the discharge time required by said first storage means to discharge through said third resistive means from said final voltage to a predetermined voltage whereby the resultant voltage on said first storage means is representative of one rectangular co-ordinate of said centroid in the plane containing said area and the resultant voltage on said second storage means is representative of the second rectangular co-ordinate of said centroid in said plane.

Claim 8

Apparatus according to claim 4 wherein each of said first, second and third storage means is a capacitive storage means.

Claim 9

Apparatus according to claim 5 wherein said first, second and third storage means comprise first, second and third capacitors respectively and said first, second and third resistive means comprise first, second and third resistors each of a resistance value which is inversely proportional to the value of the respective capacitor.

Claim 10

Apparatus in accordance with claim 6 in which all of said capacitors have equal capacitance value and all of said resistors have equal resistance value.

Claim 11

Apparatus for determining the position and orientation of an object for providing pick-up signals to a work member, said object always presenting the same surface area in one direction including: a. a scanning device adapted to be directed at said object from said one direction; b. first means for causing said scanning device to scan said object in a substantially rectangular raster pattern to locate the centroid of said area and to provide first signals indicative of the location of said centroid; c. second means for causing said scanning device to scan said object in a substantially spiral pattern towards the located centroid; d. third means responsive to the first incidence of said spiral scan pattern with the object to provide a second signal corresponding thereto; e. fourth means responsive to said second signal and said first signals to calculate the position of a predetermined pick-up part of said object; and f. fifth means in combination with said third and fourth means for providing further resultant signals indicative of the position and relative orientation of said pick-up part to said work member.

Claim 12

Apparatus for determining the position and orientation of an object for providing pick-up signals to a work member, said object always presenting the same surface area in one direction including: a. a scanning device adapted to be directed at said object from said one direction; b. first means for causing said scanning device to scan said object in a substantially rectangular raster pattern to locate the centroid of said area and to provide first signals indicative of the location of said centroid; c. second means for causing said scanning device to scan said object in a substantially spiral pattern towards the located centroid; d. third means responsive to the first incidence of said spiral scan pattern with the object to provide a second signal corresponding thereto; e. fourth means responsive to said second signal and said first signals to calculate the position of a predetermined pick-up part of said object; and f. fifth means in combination with said third and fourth means for providing further resultant signals indicative of the position and relative orientation of said pick-up part to said work member.

Claim 13

Apparatus according to claim 8 wherein said scanning device is a television camera having an electrostatic camera tube forming a part of the scanning system.

Claim 14

Apparatus according to claim 8 wherein said first means includes: a. sixth means for causing said scanning device to electronically scan said area in a substantially rectangular raster pattern, each line scan of said raster being at a predetermined respective voltage; b. seventh means for generating a line scan voltage having a first fixed value at one end of the line scan and a second fixed value at the other end of the line scan, said first and second fixed voltages being the same and the rate of variation therebetween being the same for each line scan; c. eighth means for obtaining a first summated final voltage by summing a quantity proportional to each predetermined respective voltage for the duration of time the corresponding line scan is incident on the area; d. ninth means for obtaining a second summated final voltage by summing the respective portions of the line scan voltage for the duration of time the corresponding line scan is incident on said area; e. tenth means for producing a summated voltage proportional to the time durations of the incidence of the respective line scans on the area; f. eleventh means for determining the particular time taken for said summated quantity to decrease at a constant rate to a predetermined value; and g. twelfth means for causing said first summated final voltage and said second summated final voltage to decrease at said constant rate for said particular time whereby the resultant voltage corresponding to said first summated voltage is representative of one rectangular co-ordinate of said centroid in the plane containing said area and the resultant voltage corresponding to said second summated voltage is representative of the second rectangular co-ordinate in said plane.

Claim 15

Apparatus according to claim 10 wherein: a. said eighth means is a first storage means for storing each predetermined respective voltage for the duration of time the corresponding line scan is incident on said area; b. said ninth means is second storage means for storing the respective portion of the line scan voltage for the duration of time the corresponding line scan is incident on said area; c. said tenth means is third storage means for storing a constant voltage for the duration of time each line scan is incident on said area so as to assume a final voltage representative of the area scanned; d. said eleventh and twelfth means including first, second and third resistive means, each of the same resistance value; e. first discharge means for discharging said first storage means through said first resistive means; f. second discharge means for discharging said second storage means through said second resistive means; g. third discharge means for discharging said third storage means through said third resistive means; and, h. control means for controlling the discharge time of said first and second storage means so as to be equal to the discharge time required by said first storage means to discharge through said third resistive means from said final voltage to a predetermined voltage whereby the resultant voltage on said first storage means is representative of one rectangular co-ordinate of said centroid in the plane containing said area and the resultant voltage on said second storage means is representative of the second rectangular co-ordinate of said centroid in said plane.

Claim 16

Apparatus according to claim 11 wherein each of said first, second and third storage means is a capacitive storage means.

Claim 17

Apparatus according to claim 10 wherein said eighth, ninth, tenth, eleventh and twelfth means each comprise digital means.

Claim 18

Apparatus according to claim 13 including pre-set potentiometers to control the movement of said work member over said pick-up part whereby said object can be picked up by said work member.

Claim 19

Apparatus according to claim 10 wherein: a. said third means initiates a predetermined voltage waveform at the commencement of said spiral scan pattern from a predetermined point and said second signal is a pulse having the magnitude of said voltage waveform at said first incidence; b. gating means for gating said pulse with a relatively wide pulse to provide a gate output which is representative, in time, of the angular position of said first incidence; c. delay means is provided to delay said gate output pulse by a time corresponding to the angle O between the point on said object corresponding to said first incidence and said pick-up part of said object; and, d. the delayed gate output pulse from said delay means being thus indicative of the position of said pick-up part whereby said further resultant signals can be provided.

Claim 20

Apparatus according to claim 15 wherein said predetermined voltage waveform is the vertical scan voltage waveform.

Claim 23

The method in accordance with claim 17 which includes charging from a constant voltage during the period of incidence of each line on said surface during the scanning of a complete raster pattern thereby to obtain a sum having a value of which is representative of the area of said surface.

Claim 24

The method in accordance with claim 18 which includes supplying constant voltage signals to a capacitor whereby the built up voltage on the capacitor at the end of the scanning of a complete raster pattern has a value representative of the area of said surface.

Claim 25

The method in accordance with claim 17 which includes supplying said voltage signals to a capacitor whereby the built up voltage on the capacitor at the end of the scanning of a complete raster pattern represents said sum.

Claim 26

The method in accordance with claim 20 which includes reducing said built up voltage at a predetermined rate for a predetermined length of time to effect said dividing.

Claim 27

The method in accordance with claim 20 which includes supplying said constant voltage signals to a capacitor whereby the built up voltage on the capacitor at the end of the scanning of a complete raster pattern has a value representative of the area of said surface, determining the period of time required to reduce the built up voltage on the last mentioned said capacitor at the end of the scanning of a complete raster pattern down to a predetermined value at a predetermined rate, and reducing the built up voltage on the first mentioned capacitor at the same rate and for the same period of time to effect said dividing.

Claim 28

The method in accordance with claim 17 which includes individually summing voltage signals representative of each of said X and Y frame voltages of each line during the period of incidence of the respective line on the surface during the scanning of a complete raster pattern, and dividing each thus obtained sums by a value representative of the area of said surface thereby to obtain the values of the X and Y frame voltages which correspond to said centroid.

Claim 29

The method in accordance with claim 23 which includes supplying the respective voltage signals to respective capacitors whereby the built up voltages on said capacitors at the end of the scanning of a complete raster pattern represent said sums.

Claim 30

The method in accordance with claim 24 which includes reducing said built up voltages at the same predetermined rate for the same predetermined length of time to effect said dividing.

Claim 31

The method in accordance with claim 24 which includes supplying said constant voltage signals to a capacitor whereby the built up voltage on the capacitor at the end of the scanning of a complete raster pattern has a value representative of the area of said surface, determining the period of time required to reduce the built up voltage on the last mentioned said capacitor at the end of the scanning of a complete raster pattern down to a predetermined value at a predetermined rate, and reducing the volages on the first mentioned capacitors at the same rate and for the same period of time to effect said dividing

Claim 32

The method in accordance with claim 23 which includes charging from a constant voltage during the period of incidence of each line on said surface during the scanning of a complete raster pattern thereby to obtain a sum having a value of which is representative of the area of said surface.

Claim 33

The method in accordance with claim 27 which includes supplying constant voltage signals to a capacitor whereby the built up voltage on the capacitor at the end of the scanning of a complete raster pattern has a value representative of the area of said surface.

Claim 36

The method in accordance with claim 29 which includes supporting said surface inside the limits of said raster pattern with a contrasting background surrounding said surface and extending therefrom at least to the limits of said raster pattern.

Claim 37

The method in accordance with claim 29 which includes selecting each said resistor such that it has a resistive value inversely proportional to the value of the respective capacitor.

Claim 38

The method in accordance with claim 31 which includes selecting all of said capacitors so as to be of equal capacitive value whereby all of said resistors are of equal resistive value.