GB2277169A - Control systems for a camera - Google Patents

Abstract

The control system comprises means for recording the movement of a camera in selected one or more of the pan, tilt and/or roll directions and means for replaying the recording to effect movement of the camera in one or more of the selected motions. In any motion not selected manual control of the camera can be effected. <IMAGE>

Description

C:ONTRC)L SYSTEMS The present invention relates to control systems and more particularly to a control system for a camera.

When making a film it is often necessary fur short qutnccs to b: repeated. This is usually done by the operator using his skill to repeat the sequence.

This often results in part of a sequence nol being repeated exactly and also requires the continued presence of a skilled operator.

The present invention seeks to provide a solution to the above technical problem by providing a control unit whicl is capable of storing (memorising) the movements of a camera during a first sequence and then controlling the movement of the camera during a second sequence to cause the camera to repeat all or part of the movements of the first sequence.

The present invention therefore provides in a first general aspect a control unit for a camera said control unit contprising means for causing said camera to move in an X, Y or Z axis and including means for recording the movement of the camera in any one or more of said axes during a first sequence by storing signals representive of said movement in any one or more of said axes and including control means responsive to said stored signals, said control means being operative to cause said camera to repeat in a second sequence the movement, in one or more of said X, Y or Z axes, of the first sequence Preferably the control unit additionally has means for superimposing on said camera movement a desired effect.

Such desired effects may be for example, earthquake, sea motion, car/air motion, train motion, speed/vibration or other similar motions The control unit may in a preferred embodiment store only certain movements, thereby allowing in the second sequence other non stored movements to be manually L:ontrOlled.

By way of example assume that the camera is capable of pan, tilt and roll movements and in a first sequence e camera is moved in all three. If only the pan movement is recordtxl en in the second sequence the camera will, when activated, pan in an identical manner to the first sequence. However, the operator will have manual control of the tilt and roll of the camera.

Embodiments of the present invention will now be described, by way of example with reference to the accompanying drawings in which: Figure 1 shows diagrammatically a control system according to the present invent;on; Figure 2 shows diagrammatically the configuration of switch A; Figure 3 shows diagrammatically the cwifguration of switch B; Figure 4 shows diagrammatically the configuration of switch C; Figure 5 shows diagrammatically the configuration of switch D, and Figure 6 shows block diagrammatically the electronic control circuitry for the control system of Figure 1.

With reference now to figure 1 there is shown diagrammatically a camera arrangement 10 connected via a control cable 20 to a control unit 30.

The camera arrangement 10 comprises a camera 12 mounted on a three axis X, Y, Z gimbal 14 and able to be moved using Harmonic Drive Servos coupled to positioning encoders and Watson, or similar solid state angular rate sensors. This enables the camera arrangement 10 to be remotely controlled giving movement of the camera in all three axes X, Y & Z. The gimbal 14 preferably includes slip rings in each axis to allow infinite angular movement.

The control cable 20 may be any sui2D cable and is preferably up to 100 meters in length. Alternatively an RF control link using suitable transmitters and receivers shown diagrammatically at 16 and 32.

The controller 30 preferably comprises three control wheels 34, 36, 38 which respectively remotely control accurately the three axes of movement of the camera 12 and a joystick 40 which may be used for coarse control of the three axes as an alternative to use of the wheels 34, 36, 38.

To this extent the controller 30 may be similar to the EURO system 3 but in order to provide the control functions of the present invention it is modified to incorporate specific additional components. A 64 byte RAM board 42 and an encoder interface board 44 are coupled to the EURO system 3 to allow certain unique: memory features which are controlled, at least in part by control switches A, 13, C & D referenced 46, 48, 50 & 52 in Figure 1. A record button 54 and a cue button 56 are provided to commence respectively recording and replay of movements.

With reference now to Figure 6, the cunlrpI system is shown block diagrammatically and the functions of switches A, B, C & D will be explained by reference to Figures 2 to 5. In general however, the system is able to selectively record the movement of one or more of the control wheels 34, 36, 38 in memory 42 the selection being by the positioning of switches A, B, C & D.

Thus the electronic system allows the operator to record the movements he wishes to my out by moving the control wheels 34, 36, 38 committing the required movements to the memory 42 via switches A, B, C & D thereby allowing repeated replication of the camera motion. In addition, using switch C the operator has the optioii to select a preprogrammed motion specified in Figure 4 and the load configuration can be selected to suit optimum gains suitable for the camera size and weight using switch D as specified in Figure 5.

The system is designed to fit onto any standard MOY fitting which is an international attachment for equipmwit used throughout the film industry and includes a stabilising option that allows the camera to remain level throughout dynamic movements if required.

The operation of the control system will now be described for the specific example shown in Figure 1. Each principle control will be briefly described followed by a recording sequence.

WHEELS, 34, 36, 38 - PAN TILT ROLL These are the primary control inputs to the head are used for all the motion control functions - 3 "gear speeds" are pre set for pan and tilt using switching inputs 0 1 2 3 4 5.

JOYSTlCE -40 The force trim joystick controls pan tilt and roll when selected by switch A. Pan and tilt and roll wheels 34, 36, 38 are inoptrative when in this mode.

MOTION CONTROL REQUIREMENTS - See Figure 6 1) Record switch (54) MOM using input 6).

2) Cue (playback) switch (56) (MOM using input 7).

3) LED record (60) (output 0).

4) LED start (6 > (output 1).

5) LED select (64) wheels (output 2).

6) Stored LED (66) (output 3).

7) Time LED (68) (output 4).

RECORDING SCENARIO 1) Operator selects axis he wishes to memorize control using switch B (if he has switch A selected to joystick, LED "SELECT WHEELS" (64) comes on) 2) Set control wheels in start position.

3) Press red RECORD button (54). Record LED (60) Q32.

4) 40 seconds of memory record available to each selected axis simultaneously - Time LED (68) g after 40 seconds and record LED (60) stays on.

5) Press red RECORD button (54) after motion on axis complete with wheels stationary in the finished position - or when record time runs out STORE LED (66) comes ON and axes remain stationary with pertinent wheel controls isolated. Time (68) and Record (60) LEDs go OUT, 6) Press green CUE button (56) and memorise control axes return to their START position - START LED (62) comes ON and pertinent wheel controls are isolated.

7) Press green CUE button (56) to activate motion control - START LED (62) goes OUT. Motion commences immediately button pressed. Axes remain in finished position and pertinent wheels remain inactive.

8) Press green CUE button (56) to reset and recycle programme.

STANDBY LED (62) Q.

The control switches A, B, C & D will now be described in greater detail.

The switch matrix consists of 4 rotary 8 way switches, A, B, C & BR< D which control the following functions as shown in Figures 2 to 5.

SWITCH A Control sense (wheel clock/axis clock etc). - 46 SWITCH B This switch isolates control whet:i memory and allows the operator to select individual motion control. - 48 SWITCH C Allows operator to select a pre programmed motion control that he can superimpose on top of the normal wheel control.

The motion control is continuous and is started by the CUE button. - 50 SWITCH D To select gain options for various camera mass. - 52 LEDs RECORD -60 STANDBY PLAYBACK -62 SELECT WHEELS - 64 STORE- 66 T1ME- 68 Red MOM button - RECORD - 54 Green MOM button - CUE - 56 The functions selectable by the switches A, B, C & D are shown in Figures 2 to 5 and these are further explained as follows, With reference to Figure 2 control switch A can be positioned for suspended or upright positioning of the camera mount and for either joystick (40) or wheels 34, 36, 38 movement of the camera.

In the joystick control mode the aircraft mode operates the camera in the manner of an aircraft joystick but in pan mode this operates the camera as if it were controlled by a bar giving in known manner a reverse camera action.

For the wheel motion it is necessary to identify if the camera is to roll clockwise or anticlockwise for wheel movement and this is selected for both suspended and upright mount positions.

With reference to Figure 3 the memory iriutiuri control is selected.

In position 1 stabilised level assist is selected. In position 2 all of the motions PAN, TILT and ROLL are memorised. In position d only PAN is recorded, in position 4 only TILT is recorded and in position i only ROLL is recorded and in positions 6 to 8 the combination of two of these movements oiily are recorded.

When a motion is not recorded such as ROLL in position 6 then on replay the operator is free to control that movement.

With reference to Figure 4 pre-sct programmes may be selectcd by the position of switch C.

The selection is carried out in the following sequence.

1) Select switch B to OFF.

2) Select switch C to desired progt me.

3) START LED ON, 4) Press green CUE button (56) to activate programme.

5) Select switch C to OFF position to deacdvate programme.

6) Press green CUE button (56) to switch off.

During selection of a program the wheels 34, 36, 38 remain active thereby allowing the operator free movement of the camera in addition to the superimposed motion.

With reference to Figure 5 switch D is used to select optimum loop gains within the servo systems controlling the camera to suit the weight and size of camera fitted.

The present invention therefore providcs an extremely flexible control system for cameras enabling repeated sequences as to be taken in a simple manner.

Claims (10)

1. A control unit for a camera said control unit comprising means for causing said camera to move in an X, Y or Z axis and including means for recording the movement of the camera in any one or more of said axes during a first sequence by storing signals representative of said movement in any one or more of said axes and including control means responsive to said stored signals, said control means being operative to cause said camera to repeat in a second sequence the movement, in one or more of said X, Y or Z axes, of the first sequence.

2. A control unit for a camera as claimed in claim l in which the control unit additionally has means for superimposing on said camera movement a desired effect.

3. A control unit for a camera as claimed in claim 2 in which the desired effects are earthquake, sea motion, car/air motion, train motion, speed/vibration or other similar motions.

4. A control unit for a camera as claimed in any one of claims 1 to 3 which stores only certain movements, thereby allowing in the second sequence other non stored movements to be manually controlled.

5. A control unit for a camera as claimed in any one of claims l to 4 including servo means for controlling the camera to suit the weight and size of the camera.

6. A control unit for a camera as claimed in any one of claims 1 to 5 including a plurality of switches operative to select the recording of camera motion in any one or more of the pan, tilt and roll motions.

7. A method of controlling the motion of a camera comprising recording a first sequence of movements of a camera in one or more of pan tilt and/or roll motions, replaying the recording and causing the camera to automatically repeat the sequence of movements in one or more of the pan, tilt and/or roll sequences.

8. A method of controlling the motion of a camera as claimed in claim 7 in which the motion of the camera can be additionally enhanced by the superiinposition of desired special effects on the recorded motion.

9. A control unit for a camera substantially as described with reference to the accompanying drawings.

10. A method of controlling the motion of a camera substantially as described with reference to the accompanying drawings.