WO1992015819A1

WO1992015819A1 - Camera suspension system

Info

Publication number: WO1992015819A1
Application number: PCT/CA1992/000085
Authority: WO
Inventors: Jim Rodnunsky; Jones Iain Weir
Original assignee: Jim Rodnunsky; Jones Iain Weir
Priority date: 1991-03-01
Filing date: 1992-03-02
Publication date: 1992-09-17
Also published as: CA2037387A1; AU1365192A

Abstract

A camera suspension system for use in aerial filming has a suspension cable (10), and a camera support (16) for carrying a camera (24) and, if required also a camera operator (20). The camera support (16) is suspended from the suspension cable (10) by a trolley (14) having a prime mover, which may be an hydraulic drive of an electrical drive motor, for displacing the camera support (16) along the suspension cable (10), so that the trolley (14) and therewith the camera support (16) are self-propelled.

Description

CAMERA SUSPENSION SYSTEM

The present invention relates to a camera suspension system and more particularly to a system for suspending a camera and displacing the suspended camera along an aerial path of travel.

In the photography of objects moving through a considerable distance, for example in the filming of a skier travelling down a ski run, the camera used for the filming must, at the present time, either be kept at a fixed location and rotated as the object passes by, or must be carried on a truck or other vehicle travelling along a track or carried in a helicopter.

All of these alternatives are often unsatisfactory.

Thus, filming from a fixed location has the disadvantage that the object being filmed is, for most of the filming, located at a relatively large distance from the camera and is only close up as it passes by the fixed location.

The use of tracks is often unfeasible because of unsuitable terrain, especially on ski runs, and the use of helicopter necessitates that the object be filmed from a relatively great distance if disturbance of the surroundings of the object by the helicopter is to be avoided.

It is accordingly an object of the present invention to provide a novel camera suspension system which enables a camera to be moved, for example in the vicinity of an object being filmed by the camera, without the use of a track- or air-borne camera. According to the present invention, there is provided a camera suspension system, comprising a suspension cable, camera support means for carrying a camera and a camera operator and means for suspending the camera support means from the suspension cable. The suspending means includes drive means for displacing the suspending means and therewith the camera support means along the suspension cable and the drive means comprises a prime mover so that the suspending means is self-propelled.

By arranging the suspension cable along the expected path of travel of a moving object, for example along a ski run, and by causing the camera support means to be displaced at an appropriate time and speed along the suspension cable, the camera, which may be a photographic or other movie camera or a television camera, can be kept close to the object during the filming of the object. By this means, for example when filming a skier, the viewer of the event being filmed has the impression of travelling with the skier and can closely observe the actions of the skier and the variations in the path over which the skier is travelling.

The camera support system is preferably selectively rotatable about a vertical axis to facilitate the filming operation, and it has been found to be advantageous to employ second cable as a drive cable separate but close to the suspension cable.

In a preferred embodiment of the invention, the drive means comprise such a drive cable, which is wrapped around a pair of driven and laterally relatively offset drive pulleys mounted on the suspending means.

The invention will be more readily understood from the following description of a preferred embodiment thereof when taken in conjunction with the accompanying drawings, in which;

Figure 1 shows a diagrammatic side view of a camera suspension system according to the preferred embodiment of he present invention?

Figure 2 shows a plan view of a trolley forming part of the camera support system of Figure 1;

Figure 3 show a view in side elevation of the trolley of Figure 2 and of a camera support carried thereby;

Figure 4 shows a diagrammatic view of a pair of pulleys of the trolley of Figure 2 wrapped by a drive cable;

Figure 5 shows a view in perspective of the camera support of Figure 2; and

Figure 6 shows a view in perspective of a cable guide.

The camera suspension system illustrated in Figure 1 of the accompanying drawings has a suspension cable 10, a drive cable 12 and a trolley indicated generally by reference numeral 14. The trolley 14 is carried by the suspension cable 10 and is in driving engagement with the drive cable 12, as described in greater detail below, for displacing the trolley 14 along the cables 10 and 12.

A camera support indicated generally by reference numeral 16 is suspended from the trolley 14 and has a seat 18 for a camera operator 20 and a camera mounting 22 for a movie or television camera 24, which in the illustration of Figure 1 is being used to film or "shoot" a skier 25 travelling down a ski run. The cables 10 and 12 are shown strung between a pair of posts 26. However, it is to be understood that the present invention is nt restricted to such an arrangement of only two posts or other supports for the cables 10 and 12. Thus, the cable 10 and 12 can be strung over three or more support posts or other supports, in a manner analogous to a ski lift or cable car suspension system.

The trolley 14, which is illustrated in greater detail in Figures 2 and 3, has an upper framework indicated generally by reference numeral 30 and a lower framework indicated generally by reference numeral 32, which is carried by the upper framework 30.

The upper framework 30 has two parallel, longitudinally extending beams 34, between which a pair of drive pulleys 36 are rotatably mounted on transverse shafts 37. Each drive pulley 34 is provided with a brake device 38, which comprises a spring brake and a hydraulic brake, for braking the travel of the trolley 14 long the cables 10 and 12.

The drive pulleys 36 are driven by hydraulic motors 40 through drive belts 42 and belt pulleys 44 on the shafts 37.

Hydraulic fluid under pressure is supplied to the hydraulic motors 40 from a hydraulic pump 46 under the control of a control valve 48. The hydraulic pump 46 is driven by an i.e. engine 47 which, with the pump 46, the valve 48, a fuel tank 49 and a hydraulic fluid reservoir 50, are mounted on the lower framework 32.

As shown in Figure 4, the drive cable 12 is looped around the two pulleys 36 so as to have an upper run 52 which extends over both of the drive pulleys 36 and a lower run 53 which extends beneath the pulleys 36. This arrangement of the drive cable 12 and the pulleys 36 has been found to provide good frictional engagement and thus sufficient traction, upon rotational driving of the pulleys 36 by the hydraulic motors 40, to drive the trolley 14 and therewith the camera support 16 along the drive cable 12 and the suspension cable 10.

In order to avoid binding of the drive cable 12 as it wraps the pulleys 36, the pulleys 36 are offset slightly from one another in the transverse direction, i.e. in the direction of the axes of the shafts 37.

The lower framework 32 is releasably secured by bolts 52 to the upper framework. With this arrangement, the lower framework 32, together with the i.e. engine 47, the hydraulic pump 46, the control valve 48, the fuel tank 49 and the hydraulic fluid reservoir 50, can readily be released and removed from the upper framework 30. It is then possible to replace these components by another lower framework (not shown) which is similar to the lower framework 32 by which is equipped with an electric motor and battery (not shown) as a prime mover for driving the drive pulleys 36. The use of such an electric drive may be preferable in some circumstances, for example when silent operation of the system is a requirement.

The upper framework 30 includes, at each end, a pair of vertical, laterally spaced end members 54, between which an upper pulley 56 and a corresponding but smaller lower pulley 58 define a nip for receiving the suspension cable 10. The four pulleys 56 and 58 movably support the trolley 14 on the suspension cable 10.

At each end of the trolley 14, a pair of guides 60 and 62 guidingly engage the suspension cable 10 and the drive cable 12, respectively. As shown in Figure 6, which illustrates one of these guides 62, a pair of horizontal rollers 61 and a pair of vertical rollers 63 are spaced apart to receive the drive cable 12 therebetween. The rollers 61 and 63 are rotatably supported at their ends in a housing 65. The construction of the guides 60 is similar to that of the guides 62 and is therefore not illustrated or further described. The guides 60 and 62 are secured on the outer ends of arms 64 projecting from transverse cross-members 66 connecting the longitudinal beams 34 and serve to guide the cables 10 and 12 securely onto the pulleys 54, 56 and 36.

Referring now to Figure 5, the camera support 16 has a framework formed by three rigid, downwardly extending tubular suspension members 70, 71 and 72 which at their lower ends are connected to and carry a circular base 74. The upper ends of the suspension members 70 - 72 are fixedly and rigidly connected to a vertical tubular member 75 and a horizonal brace 76 connects the upper end portions of the suspension members 70 and 72. Consequently, the framework of the camera support system is a rigid assembly of members which counteracts flexing of the camera support 16 and consequential shaking of the camera 24 during travel of the camera support 16 along the cables 10 and 12.

A horizontal, annularly curved tubular rail 78 is connected at opposite ends to the suspension members 70 and 72 and extends around the rear of the seat 18, which is mounted on a seat support 79. At the front of the camera support 16, the camera mounting 22, which is annularly curved, is secured at opposite ends to the suspension members 70 and 72 and serves to carry the camera 24.

On the base 74 of the camera support 16 there is mounted a horizontal bar 78, which carries a pair of foot Dedals 80 and 81. The foot pedal 80 is adjustable, by appropriate movement of the operator's foot, to correspondingly adjustably control the valve 48 and thus the driving of the trolley 14 and therewith the camera support 16 along the cables 10 and 12.

The foot pedal 81 serves to adjustably control a hydraulic motor 84, which is associated with a damped universally pivotable joint connecting the tubular member 75 and the trolley 14. The hydraulic motor 84 serves to rotate the camera support 16 about the vertical axis of the tubular member 74, for example for horizontally panning the camera 24.

The tubular member 75 may alternatively be rigidly connected to the trolley 14 in cases where it is preferred to avoid swinging of the camera support 16 relative to the trolley 14.

The camera support 16 also has a control panel 85 secured to the suspension member 70 and including various dial for displaying the speed of travel of the trolley 14, etc.

The trolley 14 is enclosed in a housing which is illustrated diagrammatically in broken lines, and indicated by reference numeral 86 in Figure 1. The housing 86 is made of fiberglass but may alternatively be made of metal or any other suitable material. The housing 86 has a top 88 which, as illustrated in Figure 2, is formed with openings 89 through which the drive cable 12 extends.

As will be apparent to those skilled in the art, various modifications may be made to the above-described apparatus within the scope of the invention as defined by the appended claims. For example, the system may be modified so that the camera 24 can be operated by remote control, in which case the camera operator 20 is not needed in the camera support 16 but can be positioned at a remote, fixed location.

Also, instead of using separate drive and support cables, a single cable can be used for both the suspension and the propulsion of a self-propelled trolley different from the trolley 14.

Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A camera suspension system, comprising: a suspension cable; camera support means for carrying a camera and a camera operator; and means for suspending said camera support means from said suspension cable; said suspending means including drive means for displacing said suspending means and therewith said camera support means along said suspension cable; said drive means comprising a prime mover so that said suspending means is self-propelled.

2. A camera suspension system as claimed in claim 1, further comprising means for selectively adjustably rotating said camera support means about a vertical axis relative to said suspension cable for correspondingly varying the angle of the camera.

3. A camera suspension system as claimed in claim 1, wherein said suspending means further comprises means for braking the travel of said camera support means along said suspension cable.

4. A camera suspension system as claimed in claim 1, wherein said drive means comprise a drive cable extending along said suspension cable, pulley means on said suspending means for frictional driving engagement with said drive cable and means for rotating said pulley means.

5. A camera suspension system as claimed in claim 4, wherein said pulley means comprise a pair of pulleys spaced apart in the longitudinal direction of said drive cable, said drive cable being wrapped in a loop around said pulleys so as to have an upper run extending over both of said pulleys and a lower run extending beneath both of said pulleys.

6. A camera suspension system as claimed in claim 5, wherein said pulleys are offset relative to one another in a direction transverse to said drive cable to counteract binding of said drive cable at said pulleys.

7. A camera suspension system as claimed in claim 1, further comprising selectively adjustable control means on said camera support means for controlling the driving of said suspending means along said suspension cable by said drive means.

8. A camera suspension system as claimed in claim 7, wherein said control means include a foot pedal for controlling the displacement of said suspending means along said suspension cable.

9. A camera suspension system as claimed in claim 1, wherein said camera support means comprise swivel means connecting said camera support means to said suspending means for rotation about a vertical axis relative thereto and means for selectively effecting the rotation of said camera support means about the vertical axis.

10. A camera suspension system as claimed in claim 1, wherein said camera support means comprise a plurality of rigid, downwardly extending suspension members, means connecting upper ends of said suspension members to one another, a camera operator's seat located between said suspension members, a camera mounting located in front of said camera operator's seat and means connecting said camera operator's seat and said camera mounting to said suspension members, said connecting means and said suspension members forming a rigid assembly.