Regulation 3.2 AUSTRALIA PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT ORIGINAL Name of Applicant: Stephen Leo Haggett Actual Inventor: Stephen Leo Haggett Address for Service: C/- MADDERNS, First Floor, 64 Hindmarsh Square, Adelaide, South Australia, Australia Invention title: OVERRIDE SYSTEM The following statement is a full description of this invention, including the best method of performing it known to us.
CLAIM OF PRIORITY The present application for patent claims priority from Australian Provisional Patent Application No. 2008906099 entitled "OVERRIDE SYSTEM", filed 25 November 2008, which is hereby expressly incorporated by reference herein in its entirety. 5 TECHNICAL FIELD The present invention relates to the use of machine operated equipment for excavation and other similar activities. In a particular form the present invention relates to an override system for preventing damage to underground infrastructure. 10 BACKGROUND One of the primary concerns when carrying out an excavation task such as trenching, or the like is the possibility of inadvertently destroying underground infrastructure in the process of digging into the ground. Underground infrastructure can range from water and gas piping to 15 electrical and communication cables. Especially where large scale heavy duty excavators and other similar equipment are being used, the operator of the excavator will be seated in a cabin positioned some distance away from the bucket which will be digging into the earth. As a consequence of this, the operator cannot easily observe the exact location that is being excavated, making it extremely difficult to see if there is any underground infrastructure at 20 this location. One approach to address this problem has been to require operators of excavation or drilling equipment to obtain plans of the area being excavated which will indicate the underground infrastructure so that an operator can plan accordingly to avoid this infrastructure. To 25 facilitate this process, various telephone hot lines have been implemented, whereby an operator intending to excavate, dig or drill in a given area can call a central authority and obtain any information regarding underground infrastructure that may be present. However, these approaches have a number of disadvantages as they firstly rely on the operator obtaining the relevant information and secondly that the relevant information is accurate and may be 30 easily interpreted by the operator. As a consequence of this, there are still multiple occurrences where underground infrastructure is damaged with the resultant lack of services to the community and the added expense of carrying out the repairs. This can have particularly serious consequences where a 35 fibre optic telecommunication cable is cut, resulting in many thousands of phone lines being inoperable and in some circumstances emergency communication services being severely affected. 2 It is an object of the present invention to provide an override system capable of aiding an operator of machine operated equipment to avoid the inadvertent damage of underground infrastructure when excavating, digging or drilling a region. 5 SUMMARY In a first aspect the present invention accordingly provides an override system for the control of machine operated equipment carrying out a task remote from a first operator operating the machine operated equipment, the override system including: 10 a controller operable by a second operator located proximate to a location of the task; a communication link between the controller and the machine operated equipment, wherein on actuation of the controller an override signal is sent via the communication link to the machine operated equipment to override and interrupt the further functioning of the machine operated equipment. 15 Preferably, the machine operated equipment is attached to a mobile platform. Preferably, the mobile platform is further operable by the first operator. 20 Preferably, the machine operated equipment is powered by a hydraulic system. Preferably, the override signal is sent to an interrupt circuit in the hydraulic system to interrupt the flow of fluid in the hydraulic system. 25 Preferably, the interrupt circuit is a cut off valve operable to cut off fluid flow to a valve block that forms part of the hydraulic system. Preferably, a hydraulic pump providing fluid pressure for the hydraulic system is caused to cease operating responsive to the override signal. 30 Preferably, the system includes braking or clutch means responsive to the override signal to interrupt the further functioning of the machine operated equipment. Preferably, the machine operated equipment is operable to excavate, dig or drill a region. 35 3 In a second aspect the present invention accordingly provides a method for overriding the operation of machine operated equipment carrying out a task remote from a first operator operating the machine operated equipment, the method including: sending an override signal via a communication link to the machine operated 5 equipment from a second operator located proximate to the location of the task; and interrupting the operation of the machine operated equipment responsive to the override signal. BRIEF DESCRIPTION OF THE DRAWINGS 10 An illustrative embodiment of the present invention will be discussed with reference to the accompanying drawing wherein: FIGURE 1 depicts the use of an override system according to an illustrative embodiment of the present invention. 15 DETAILED DESCRIPTION Referring now to Figure 1, there is depicted the use of an override system according to an illustrative embodiment of the present invention. In this illustrative embodiment, the machine operated equipment is an extendable excavating arm I 10 terminating in a pivotably mounted bucket 120 which is employed to dig or excavate trench 200. 20 Excavating arm 1 10 is attached to a main chassis 140 incorporating a cabin 130 housing a first operator. Main chassis 140 is rotatably mounted to caterpillar tracks 150, thereby forming a mobile platform or excavator 100 as is known in the art. Main chassis 140 also incorporates the engine and hydraulic systems which function to drive the hydraulic rams (not 25 shown) which power excavating arm 1 10. As would be appreciated by those skilled in the art, the operator of excavator 100 cannot easily view the bucket 120 given that it is both some distance from the position of the operator who is located in the cabin 130 and furthermore that it is obscured by the edge of 30 trench 200. In this situation, the operator of excavator 100 is unable to see the fibre optic cable 210 which has been partially uncovered. According to the present invention, a second operator 300 located proximate to and having a better view of the location at which the excavation is occurring is able to closely view and 35 observe the region which is being excavated. In this illustrative embodiment, the second operator 300 positions themselves to be able to view between the teeth of bucket 120 as it excavates. When this second operator 300 determines that there is some underground 4 infrastructure such as a fibre optic cable 210 or the like which may be damaged by the operation of excavating arm 1 10, the second operator actuates controller 3 10 which sends an override signal via communication link 320 to the hydraulic system that powers excavation arm 1 10 and bucket 120 to interrupt and override their operation in the process preventing any 5 damage to the underground infrastructure. Whilst in this illustrative embodiment, communication link 320 between controller 310 and machine operated equipment or excavation arm 110 is via a cable, the communication link may equally be implemented using wireless means such as provided by an infrared, mobile or 10 wireless network connection. In this embodiment, when controller 310 is actuated, the override signal is sent via communication link 320 to an interrupt circuit in the form of a solenoid operated cut off valve situated in the hydraulic circuit located prior to the valve block which functions to distribute 15 hydraulic fluid under pressure to the various hydraulic rams on the excavator. In this manner, once controller 310 is actuated, power will be cut to excavation arm 1 10 as fluid flow pressure is cut off to the valve block causing excavation arm 110 to rapidly become and remain stationary due to the almost instantaneous removal of hydraulic power. In another embodiment, the override signal may also cause the hydraulic pump that provides fluid 20 pressure and forms part of the hydraulic system to cease operating. In the example of electrical driven machine operated equipment, actuation of controller 310 will function as a switch to cut off electrical power to the one or more electrical motors driving the machine operated equipment, once again causing the equipment to become static. 25 Depending on the mechanical arrangement of the machine operated equipment, it may also be necessary to incorporate a braking or clutch arrangement also responsive to the override signal to apply a braking force or force disengagement facility to the machine operated equipment. 30 As would be appreciated by those skilled in the art the present invention may be applied to different types of machine operated equipment that are employed to excavate, dig or drill a region having underground infrastructure. In one embodiment, the invention may be applied to a backhoe or excavating arm attached to the rear of a tractor front end loader as opposed to 35 a crawler as in the excavator embodiment described herein. In another embodiment, the present invention may be directed to a drilling rig. 5 In those situations where the second operator is unable to directly view the interface region between the machine operated equipment and the region being excavated, then equipment such as a fibre optic camera or other equivalent visual inspection means may be employed to allow the operator to detect any underground infrastructure. 5 A brief consideration of the above described embodiment will indicate that the invention provides an extremely simple, economical feature for machine operated equipment which allows the first operator to concentrate on operating the equipment according to the task at hand and provides for a second operator whose main function is to detect whether a condition 10 arises where operation of the equipment must be interrupted and allows them to directly override and interrupt the operation of the machine operated equipment. This allows the second operator to concentrate fully on preventing any damage to underground infrastructure or the like. 15 Whilst the present invention has been described in relation to excavation equipment it will be appreciated that the invention will have other applications consistent with the principles described in the specification. The reference to any prior art in this specification is not, and should not be taken as, an 20 acknowledgement of any form of suggestion that such prior art forms part of the common general knowledge. Although an illustrative embodiment of the present invention has been described in the foregoing detailed description, it will be understood that the invention is not limited to the 25 embodiment disclosed, but is capable of numerous rearrangements, modifications and substitutions without departing from the scope of the invention as set forth and defined by the following claims. 6