Numerical control system

Claim 2

Apparatus for moving a controlled device along a path, said path comprising a number of segmental portions, each between a first point and a second point, wherein the apparatus successively receives coordinate input information for directing a corresponding movement of said controlled device, said apparatus comprising: input register means for receiving said input information and providing a digital positional error indication in at least two axes between input information and the actual position of said controlled device, rate command means responsive to said digital error indication as well as a feedrate command for generating pulse outputs in two axes having output rates proportional to said feedrate command and ratioed according to the positional error in said two axes, said rate command means comprising a digital differential analyzer for each axis, each being provided with a register to which the initial error between said first point and said second point is repeatedly added in response to the feedrate command, the pulse output of each digital differential analyzer comprising the overflow of said last mentioned register, digital servomechanism means, and positioning motors operated thereby, responsive to said pulse outputs to provide movement of said controlled device, feedback means actuated by said movement of said controlled device to provide feedback pulse information in response thereto, and means for coupling said feedback pulse information to said input register means for updating and reducing said error indication.

Claim 3

The apparatus according to claim 1 further including means responsive to a predetermined small error indication by said input register means for disabling operation of said rate command means and causing said digital servomechanism means to retain an attained position.

Claim 4

The apparatus according to claim 1 wherein said feedback means comprises a mechanical transducer providing a pulse output in response to movement of said controlled device at the rate of movement of said controlled device.

Claim 5

The apparatus according to claim 1 wherein said feedrate command is digitally controlled and variable in response to controlled acceleration or deceleration.

Claim 6

The apparatus according to claim 1 including digital means for generating a varying feedrate command dependent upon a desired acceleration.

Claim 7

Apparatus for moving a controlled device along a path, said path comprising a number of segmental portions, wherein the apparatus successively receives coordinate input information for directing a corresponding movement of said controlled device, said apparatus comprising: input register means for receiving said input information and providing a digital positional error indication in at least two axes between input information and the actual position of said controlled device, rate command means repsonsive to said digital error indication as well as a feedrate command for generating pulse outputs in two axes having output rates proportional to said feedrate command and ratioed according to the positional error in said two axes, said rate command means comprisiNg a digital differential analyzer for each axis, each being provided with a register to which said error indication is repeatedly added in response to the said feedrate command, the pulse output of each digital differential analyzer comprising the overflow of said last mentioned register, digital servomechanism means, and positioning motors operated thereby, responsive to said pulse outputs to provide movement of said controlled device, feedback means actuated by said movement of said controlled device to provide feedback pulse information in response thereto, means for coupling said feedback pulse information to said input register means for updating and reducing said error indication, means for receiving a feedrate input value, and further feedback means responsive to said feedrate input value and a pulse output of said rate command means for generating a feedrate command causing said rate command means to produce an output pulse rate in accordance with said feedrate input value.

Claim 8

Apparatus for moving a controlled device along a path, said path comprising a number of segmental portions, wherein the apparatus successively receives coordinate input information for directing a corresponding movement of said controlled device, said apparatus comprising: input register means for receiving said input information and providing a digital positional error indication in at least two axes between input information and the actual position of said controlled device, rate command means repsonsive to said digital error indication as well as a feedrate command for generating pulse outputs in two axes having output rates proportional to said feedrate command and ratioed according to the positional error in said two axes, said rate command means comprisiNg a digital differential analyzer for each axis, each being provided with a register to which said error indication is repeatedly added in response to the said feedrate command, the pulse output of each digital differential analyzer comprising the overflow of said last mentioned register, digital servomechanism means, and positioning motors operated thereby, responsive to said pulse outputs to provide movement of said controlled device, feedback means actuated by said movement of said controlled device to provide feedback pulse information in response thereto, means for coupling said feedback pulse information to said input register means for updating and reducing said error indication, means for receiving a feedrate input value, and further feedback means responsive to said feedrate input value and a pulse output of said rate command means for generating a feedrate command causing said rate command means to produce an output pulse rate in accordance with said feedrate input value.

Claim 9

Apparatus for moving a controlled device along a path, said path comprising a number of segmental portions, wherein the apparatus successively receives coordinate input information for directing a corresponding movement of said controlled device, said apparatus comprising: input register means for receiving said input information and providing a digital positional error indication in at least two axes between input information and the actual position of said controlled device, rate command means responsive to said digital error indication as well as a feedrate command for generating pulse outputs in two axes having output rates proportional to said feedrate command and ratioed according to the positional error in said two axes, digital servomechanism means, and positioning motors operated thereby, responsive to said pulse outputs to provide movement of said controlled deivce, feedback means actuated by said movement of said controlled device to provide feedback pulse information in response thereto, means for coupling said feedback pulse information to said input register means for updating and reducing said error indication, digital means for generating a varying feedrate command for providing a desired acceleration, and means coupling the last mentioned digital means to respond to the output of said feedback means for increasing said feedrate command in relation to the movement of said controlled device so that the feedrate command increases as said movement increases.

Claim 10

Apparatus for moving a controlled device along a path, said path comprising a number of segmental portions, wherein the apparatus successively receives coordinate input information for directing a corresponding movement of said controlled device, said apparatus comprising: input register means for receiving said input information and providing a digital positional error indication in at least two axes between input information and the actual position of said controlled device, rate command means responsive to said digital error indication as well as a feedrate command for generating pulse outputs in two axes having output rates proportional to said feedrate command and ratioed according to the positional error in said two axes, digital servomechanism means, and positioning motors operated thereby, responsive to said pulse outputs to provide movement of said controlled deivce, feedback means actuated by said movement of said controlled device to provide feedback pulse information in response thereto, means for coupling said feedback pulse information to said input register means for updating and reducing said error indication, digital means for generating a varying feedrate command for providing a desired acceleration, and means coupling the last mentioned digital means to respond to the output of said feedback means for increasing said feedrate command in relation to the movement of said controlled device so that the feedrate command increases as said movement increases.

Claim 11

The apparatus according to claim 7 including means for determining when said feedrate command results in a pulse output from said rate command means reaching a desired rate value, and means for thereupon maintaining said feedrate command for producing such output pulse rate until said positional error is substantially reduced.

Claim 12

The apparatus according to claim 7, including means for determining when said feedrate command results in a pulse output from said rate command means reaching a desired rate value, means for thereupon maintaining said feedrate command for producing such output pulse rate until said positional error is substantially reduced, means for detecting a decrease in positional error below a predetermined value, and means connected to said means for generating a varying feedrate command and responsive to said detection for decreasing said feedrate command and decelerating said controlled device.

Claim 13

The apparatus according to claim 9 further including means for detecting when acceleration causes movement approximately equal to the movement required for deceleration, and means for commanding an immediate decrease in said feedrate to provide a deceleration mode.

Claim 14

The apparatus according to claim 7 wherein said rate command means comprise a digital differential analyzer for each axis, each being provided with a register to which said error information is repeatedly added in response to the same feedrate command, the pulSe output of each digital differential analyzer comprising the overflow of said last mentioned register.

Claim 15

The apparatus according to claim 7 wherein said means coupling the last mentioned digital means to respond to the output of said feedback means includes additional rate command means receiving an input in response to movement of said control device as detected by said feedback means, and means for bringing about correspondence between outputs of the first mentioned rate command means and additional rate command means.

Claim 16

The apparatus according to claim 12 wherein said additional rate command means comprises a digital differential analyzer.

Claim 17

Apparatus for moving a controlled device along a path, said path comprising a number of segmental portions, wherein the apparatus successively receives coordinate input information for directing a corresponding movement of said controlled device, said apparatus comprising: input register means for receiving said input information and providing a digital positional error indication in at least two axes between input information and the actual position of said controlled device, rate command responsive to said digital error indication as well as a feedrate command for generating pulse outputs in two axes having output rates proportional to said feedrate command and ratioed according to the positional error in said two axes, said rate command means comprising a digital differential analyzer for each axis, each being provided with a reguster to which said error indication is repeatedly added in response to the said feedrate command, the pulse output of each digital differential analyzer comprising the overflow of said last mentioned register, digital servomechanism means, and positioning motors operated thereby, responsive to said pulse outputs to provide movement of said controlled device, feedback means actuated by said movement of said controlled device to provide feedback pulse information in response thereto, means for coupling said feecback pulse information to said input register means for updating and reducing said error indication, digital means for generating a varying feedrate command for providing a desired deceleration, the last mentioned digital means comprising an additional digital differential analyzer, and means coupling the last mentioned digital means to respond to the output of said input register means for decreasing said feedrate command as positional error decreases below a predetermined value and in predetermined relation with further decrease of said positional error.

Claim 18

Apparatus for moving a controlled device along a path, said path comprising a number of segmental portions, wherein the apparatus successively receives coordinate input information for directing a corresponding movement of said controlled device, said apparatus comprising: input register means for receiving said input information and providing a digital positional error indication in at least two axes between input information and the actual position of said controlled device, rate command responsive to said digital error indication as well as a feedrate command for generating pulse outputs in two axes having output rates proportional to said feedrate command and ratioed according to the positional error in said two axes, said rate command means comprising a digital differential analyzer for each axis, each being provided with a reguster to which said error indication is repeatedly added in response to the said feedrate command, the pulse output of each digital differential analyzer comprising the overflow of said last mentioned register, digital servomechanism means, and positioning motors operated thereby, responsive to said pulse outputs to provide movement of said controlled device, feedback means actuated by said movement of said controlled device to provide feedback pulse information in response thereto, means for coupling said feecback pulse information to said input register means for updating and reducing said error indication, digital means for generating a varying feedrate command for providing a desired deceleration, the last mentioned digital means comprising an additional digital differential analyzer, and means coupling the last mentioned digital means to respond to the output of said input register means for decreasing said feedrate command as positional error decreases below a predetermined value and in predetermined relation with further decrease of said positional error.

Claim 19

The apparatus according to claim 14 including means for entering positional error into said additional digital differential analyzer as positional error decreases below said predetermined value.

Claim 20

Apparatus for moving a controlled device along a path, said path comprising a number of segmental portions, wherein the apparatus successively receives coordinate input information for directing a corresponding movement of said controlled device, said apparatus comprising: input register means for receiving said input information and providing a digital positional error indication in at least two axes between input information and the actual position of said controlled deivce, rate command means responsive to said digital error information as well as a feedrate command for generating pulse outputs in two axes having output rates proportional to said feedrate command and ratioed according to the positional error in said two axes, digital servomechanism means, and positioning motors operated thereby, responsive to said pulse outputs to provide movement of said controlled device, feedback means actuated by said movement of said controlled device to provide feedback pulse information in response thereto, and means for coupling said feedback pulse information to said input register means for updating and reducing said error indication, said input register means including position register means normally updated by said feedback pulse information to provide current information on the position of said controlled device while reducing said error indication, said apparatus further including display means for receiving position information from said position register for plotting directed movement.

Claim 21

Apparatus for moving a controlled device along a path, said path comprising a number of segmental portions, wherein the apparatus successively receives coordinate input information for directing a corresponding movement of said controlled device, said apparatus comprising: input register means for receiving said input information and providing a digital positional error indication in at least two axes between input information and the actual position of said controlled deivce, rate command means responsive to said digital error information as well as a feedrate command for generating pulse outputs in two axes having output rates proportional to said feedrate command and ratioed according to the positional error in said two axes, digital servomechanism means, and positioning motors operated thereby, responsive to said pulse outputs to provide movement of said controlled device, feedback means actuated by said movement of said controlled device to provide feedback pulse information in response thereto, and means for coupling said feedback pulse information to said input register means for updating and reducing said error indication, said input register means including position register means normally updated by said feedback pulse information to provide current information on the position of said controlled device while reducing said error indication, said apparatus further including display means for receiving position information from said position register for plotting directed movement.

Claim 22

The apparatus according to claim 16, including means for coupling a pulse output from said rate command means for updating position register means in an input data checking mode.

Claim 23

The apparatus according to claim 16 wherein said display means comprises a bistable cathode ray storage tube for semi-permanently displaying a directed movement path.

Claim 24

The apparatus according to claim 16 further provided with a tape reader for receiving input information in binary coded decimal form, and a converter for converting said information into binary form for use by said input register means.

Claim 25

In apparatus for moving a controlled device along a path wherein said apparatus receives coordinate input information for directing movement of said controlled device, digital differential analyzer means responsive to input information for generating an output having a rate to which movement of said controlled device is responsive, means for digitally generating a determined feedrate, and means for comparing said output rate with said determined feedrate and in response thereto controlling the adding rate input of said digital differential analyzer means to provide an output rate proportional to said determined feedrate.

Claim 26

In apparatus for moving a controlled device along a path wherein said apparatus receives coordinate input information for directing movement of said controlled device, digital differential analyzer means responsive to input information for generating an output having a rate to which movement of said controlled device is responsive, means for digitally generating a determined feedrate, and means for comparing said output rate with said determined feedrate and in response thereto controlling the adding rate input of said digital differential analyzer means to provide an output rate proportional to said determined feedrate.

Claim 27

The apparatus according to claim 20 including means for changing said digitally generated determined feedrate to provide acceleration and deceleration on command.

Claim 28

The apparatus according to claim 21 wherein said acceleration or deceleration is adaptive to actual movement of said controlled device.

Claim 29

In apparatus for moving a controlled device along a path, wherein the apparatus receives input information for directing a movement of said controlled device, means for producing a rate signal to which the rate of movement of said controlled device is responsive, feedback meanS actuated by said movement of said controlled device to provide feedback information in response thereto, and means coupled to said means for producing a rate signal and responsive to said feedback information for increasing said rate signal as said controlled device moves to provide adaptive acceleration of said controlled device.

Claim 30

In apparatus for moving a controlled device along a path, wherein the apparatus receives input information for directing a movement of said controlled device, means for producing a rate signal to which the rate of movement of said controlled device is responsive, feedback meanS actuated by said movement of said controlled device to provide feedback information in response thereto, and means coupled to said means for producing a rate signal and responsive to said feedback information for increasing said rate signal as said controlled device moves to provide adaptive acceleration of said controlled device.

Claim 31

The apparatus according to claim 23 including means for determining when said rate signal reaches a desired feedrate value, and means coupled to said means for producing a rate signal for thereupon maintaining said rate signal at the same value for at least a predetermined proportion of said movement.

Claim 32

The apparatus according to claim 23 including means for determining when said rate signal reaches a desired feedrate value, means for thereupon maintaining said rate signal the same for a predetermined proportion of said movement, and means coupled to said means for producing a rate signal and responsive to said feedback information for decreasing said rate signal near the end of said movement in relation to the remaining distance of the desired movement.

Claim 33

The apparatus according to claim 23 including means for detecting when the increase in said rate signal causes translation of said controlled device approximately equal to the translation required for deceleration to the end of said movement, and means responsive to said detection for commanding an immediate decrease in said rate signal to provide said deceleration.

Claim 34

In apparatus for moving a controlled device along a path, wherein the apparatus receives coordinate input information for directing a corresponding movement of said controlled device, rate command means for generating an output rate signal to which movement of said controlled device is responsive feedback means actuated by movemEnt of said controlled device and coupled to the rate command means for normally ascertaining and bringing about correspondence between the actual rate of movement and the output rate signal, and means for accelerating said controlled device by gradually increasing the output rate signal of said rate command means, said means for accelerating including means responsive to said feedback means for increasing said output rate signal as said controlled device responds to the output rate signal.

Claim 35

In apparatus for moving a controlled device along a path, wherein the apparatus receives coordinate input information for directing a corresponding movement of said controlled device, rate command means for generating an output rate signal to which movement of said controlled device is responsive feedback means actuated by movemEnt of said controlled device and coupled to the rate command means for normally ascertaining and bringing about correspondence between the actual rate of movement and the output rate signal, and means for accelerating said controlled device by gradually increasing the output rate signal of said rate command means, said means for accelerating including means responsive to said feedback means for increasing said output rate signal as said controlled device responds to the output rate signal.

Claim 36

The apparatus according to claim 27 wherein said rate command means comprises a digital differential analyzer and wherein said means for accelerating said control device by gradually increasing the output rate signal of said rate command means comprises further rate command means responsive to an input from said feedback means as the feedback means is actuated by movement of said controlled device, and means for bringing about correspondence between the outputs of the rate command means.

Claim 37

The apparatus according to claim 27 wherein said means for increasing said rate signal comprises a digital differential analyzer, said digital differential analyzer receiving information in response to said feedback means related to actual movement of said controlled device and providing an overlfow rate in proportion thereto, to which said rate signal is responsive for increasing said rate signal in an adaptive manner.

Claim 38

The apparatus according to claim 27 including means for receiving a digital representation of a particular feedrate, means coupled to receive said rate signal and said digital representation of a particular feedrate for detecting when said rate signal provides said feedrate and connected to said rate command means for thereupon maintaining said rate signal through normal feedback operation for a predetermined proportion of said movement means for detecting approach of the end of movement, and means responsive to such detection for decreasing said rate signal near the end of said movement in proportion to the positional error remaining in said movement as indicated by said feedback means in combination with said input information.

Claim 39

In apparatus for moving a controlled device along a path, wherein the apparatus receives input information for directing a movement of said controlled device, first digital differential analyzer means for producing a rate signal to which the rate of movement of said controlled device is responsive, means responsive to actual movement of the device for determining the remaining portion of said movement, means for detecting when the remaining portion of said movement decreases below a predetermined value, and means including additional digital differential analyzer means and responsive to said detection for decreasing said rate signal by decreasing the adding rate input to the first digital differential analyzer means as the detected remaining portion of said movement decreases below a predetermined value, and for continuing to decrease said rate signal as said remaining portion, as ascertained by said means for determining the same, continues to decrease, for providing adaptive deceleration.

Claim 40

In apparatus for moving a controlled device along a path, wherein the apparatus receives input information for directing a movement of said controlled device, first digital differential analyzer means for producing a rate signal to which the rate of movement of said controlled device is responsive, means responsive to actual movement of the device for determining the remaining portion of said movement, means for detecting when the remaining portion of said movement decreases below a predetermined value, and means including additional digital differential analyzer means and responsive to said detection for decreasing said rate signal by decreasing the adding rate input to the first digital differential analyzer means as the detected remaining portion of said movement decreases below a predetermined value, and for continuing to decrease said rate signal as said remaining portion, as ascertained by said means for determining the same, continues to decrease, for providing adaptive deceleration.

Claim 41

In apparatus for moving a controlled device wherein the apparatus receives input information for directing a corresponding movement of said device, rate command means comprising a first digital differential analyzer means for generating a rate signal to which movement of said controlled device is responsive, feedback means actuated by movement of said controlled device, means responsive to said feedback means for determining the remaining portion of said movement, and means including a second digital differential analyzer means for decreasing said rate signal by decreasing the adding rate input to the first digital differential analyzer means when said remaining portion decreases below a predetermined value, and in substantial proportion to the portion of said movement remaining.

Claim 42

In apparatus for moving a controlled device wherein the apparatus receives input information for directing a corresponding movement of said device, rate command means comprising a first digital differential analyzer means for generating a rate signal to which movement of said controlled device is responsive, feedback means actuated by movement of said controlled device, means responsive to said feedback means for determining the remaining portion of said movement, and means including a second digital differential analyzer means for decreasing said rate signal by decreasing the adding rate input to the first digital differential analyzer means when said remaining portion decreases below a predetermined value, and in substantial proportion to the portion of said movement remaining.

Claim 43

The apparatus accordinG to claim 32 wherein said second digital differential analyzer means receives error information related to the remainder of said movement and provides an overflow rate in proportion thereto, to which said rate signal is responsive for decreasing said rate signal.

Claim 44

The apparatus according to claim 33 including means responsive to the overflow rate of the second digital differential analyzer means for providing an adding rate input to the first digital differential analyzer means causing a correspondence between the outputs of said digital differential analyzer means.

Claim 45

Apparatus for displaying input information wherein said input information is adapted to define plural successive segmental portions of a contour, said apparatus comprising: means for providing repetitive outputs representative of each said segmental portion, register means for receiving and accumulating said repetitive outputs, and bistable cathode ray storage tube means substantially continuously responsive to the accumulation in said register means for providing a visual indication of said segmental portions comprising said contour.

Claim 46

Apparatus for displaying input information wherein said input information is adapted to define plural successive segmental portions of a contour, said apparatus comprising: means for providing repetitive outputs representative of each said segmental portion, register means for receiving and accumulating said repetitive outputs, and bistable cathode ray storage tube means substantially continuously responsive to the accumulation in said register means for providing a visual indication of said segmental portions comprising said contour.

Claim 47

Apparatus for verifying input information wherein said information is adapted for directing a controlled device along a path comprising a number of segmental portions, said apparatus comprising: means for developing repetitive output information in two axes proportional to said input information for each of said segmental portions, position register means for receiving said repetitive output information and accumulating positonal coordinate information, digital to analog converter means responsive to said position register means for developing analog values in proportion to the contents of said position register means, and display means for receiving the outputs of said digital to analog converter means to provide an analog display representative of said input data as said position register means is receiving said repetitive output information, said display means comprising a cathode ray storage tube having deflection means operatively coupled to said digital to analog converter means for deflecting the electron beam thereof to produce a stored image.

Claim 48

Apparatus for verifying input information wherein said information is adapted for directing a controlled device along a path comprising a number of segmental portions, said apparatus comprising: means for developing repetitive output information in two axes proportional to said input information for each of said segmental portions, position register means for receiving said repetitive output information and accumulating positonal coordinate information, digital to analog converter means responsive to said position register means for developing analog values in proportion to the contents of said position register means, and display means for receiving the outputs of said digital to analog converter means to provide an analog display representative of said input data as said position register means is receiving said repetitive output information, said display means comprising a cathode ray storage tube having deflection means operatively coupled to said digital to analog converter means for deflecting the electron beam thereof to produce a stored image.

Claim 49

The apparatus according to claim 36 wherein said display means comprises a bistable cathode ray storage tube having a storage target, said storage tube being provided with flood gun means for retaining and displaying the contour traced by said electron beam on said storage target under the direction of said deflection means.

Claim 50

Verification apparatus for receiving successive segmental input instructions representative of a contour and for displaying the same, said apparatus comprising: means for receiving said successive segmental input instructions in digital form and providing impulse outputs at frequencies proportional to the desired segmental movement in at least two axes, and bistable cathode ray storage tube means having deflection means responsive to said impulse outputs to provide a semi-permanent display of the indicated contour, said display concurrently exhibiting plural segments of said contour.

Claim 51

Verification apparatus for receiving successive segmental input instructions representative of a contour and for displaying the same, said apparatus comprising: means for receiving said successive segmental input instructions in digital form and providing impulse outputs at frequencies proportional to the desired segmental movement in at least two axes, and bistable cathode ray storage tube means having deflection means responsive to said impulse outputs to provide a semi-permanent display of the indicated contour, said display concurrently exhibiting plural segments of said contour.

Claim 52

Verification means for checking input data representative of a contour, comprising: input register means for receiving said data and including position register means, said input register means providing a digital positional error indication in at least two axes between input information and the contents of the position register means, rate command means responsive to said digital error indication for generating pulse outputs in two axes having output rates ratioed according to the positional error in said two axes, and display means for receiving and displaying positional information from said position register means for plotting said input data.

Claim 53

Verification means for checking input data representative of a contour, comprising: input register means for receiving said data and including position register means, said input register means providing a digital positional error indication in at least two axes between input information and the contents of the position register means, rate command means responsive to said digital error indication for generating pulse outputs in two axes having output rates ratioed according to the positional error in said two axes, and display means for receiving and displaying positional information from said position register means for plotting said input data.

Claim 54

The apparatus according to claim 39 wherein said rate command means comprises a digital differential analyzer for each axis, each being provided With a register to which error information is repeatedly added, the pulse output of each digital differential analyzer comprising the overflow of said last mentioned register.

Claim 55

The apparatus according to claim 39 wherein said display means comprises a bistable cathode ray storage tube for semi-permanently displaying said contour.

Claim 56

The apparatus according to claim 39 including means for coupling an output from said rate command means for updating said position register means.

Claim 57

The apparatus according to claim 39 wherein said display means comprises a cathode ray storage tube for semi-permanently displaying said contour.

Claim 60

Apparatus for moving a controlled device along a path, said path comprising a number of segmental portions, wherein the apparatus successively receives coordinate input information for directing a corresponding movement of said controlled device, said apparatus comprising: input register means for receiving said input information and providing a digital positional error indication between input information and the actual position of said controlled device, command means responsive to said digital error information for providing a command output at a corresponding rate, servomechanism means, and positioning means operated thereby, responsive to said command output to provide movement of said controlled device, and means responsive to a predetermined small error indication produced by said input register means for substantially discontinuing said command output and switching said servomechanism means to a position retaining mode, said servomechanism means being provided with increased gain in said position retaining mode under small error conditions.

Claim 61

Apparatus for moving a controlled device along a path, said path comprising a number of segmental portions, wherein the apparatus successively receives coordinate input information for directing a corresponding movement of said controlled device, said apparatus comprising: input register means for receiving said input information and providing a digital positional error indication between input information and the actual position of said controlled device, command means responsive to said digital error information for providing a command output at a corresponding rate, servomechanism means, and positioning means operated thereby, responsive to said command output to provide movement of said controlled device, and means responsive to a predetermined small error indication produced by said input register means for substantially discontinuing said command output and switching said servomechanism means to a position retaining mode, said servomechanism means being provided with increased gain in said position retaining mode under small error conditions.

Claim 62

Apparatus for providing a display responsive to successive segmental input instructions representative of a contour, said apparatus comprising: means for receiving said successive segmental input instructions in digital form and for registering changing positional information in at least two axes as modified by said successive segmental input instructions, and a cathode ray storage tube having deflection means responsive to said positional information in said two axes, and repeatedly responsive thereto as said positional information is modified by said successive segmental input instructions, to provide a continuous contour display formed of consecutively stored and successively joined display segments which are retained by said cathode ray storage tube for viewing of a complete contour.

Claim 63

Apparatus for providing a display responsive to successive segmental input instructions representative of a contour, said apparatus comprising: means for receiving said successive segmental input instructions in digital form and for registering changing positional information in at least two axes as modified by said successive segmental input instructions, and a cathode ray storage tube having deflection means responsive to said positional information in said two axes, and repeatedly responsive thereto as said positional information is modified by said successive segmental input instructions, to provide a continuous contour display formed of consecutively stored and successively joined display segments which are retained by said cathode ray storage tube for viewing of a complete contour.