A safety system for a drilling machine

Abstract

A safety system for a drilling machine is disclosed that includes controllable drilling machine functions. The safety system has a disparity checker arranged to carry out at least one functional disparity check to determine whether a drilling machine function being implemented by the drilling machine has an associated drilling machine function instruction that correctly corresponds to the implemented drilling machine function, and / or a drilling machine function instruction provided to the drilling machine is correctly being implemented at the drilling machine. The disparity checker generates disparity data if at least one disparity condition exists. At least one sensor is used by the disparity checker to carry out the functional disparity check, and the system inhibits at least one drilling machine control in response to generation of the disparity data.

Description

[0001] A SAFETY SYSTEM FOR A DRILLING MACHINE

[0002] Field of the Invention

[0003] The present invention relates to a safety system for a drilling machine.

[0004] Background of the Invention

[0005] In the resources industry, it is common to use drilling machines to drill holes in a target mining area according to a defined drill hole pattern, then subsequently fill the holes with explosive and detonate the explosive to release material.

[0006] In one arrangement, a defined drill hole pattern is used by a drilling machine to control the path of movement of the drilling machine across the target mining area and the locations at which to drill the holes. The drilling machine may be at least partially autonomous whereby the drilling machine is provided with a drilling pattern, and the drilling machine autonomously traverses the target mining area and drills the required holes according to the drill hole pattern. In some circumstances, the drilling machine is manually controlled from a remote location.

[0007] However, significant safety risks exist when the drilling machine operates at least partially autonomously, because it may be difficult to identify when a problem exists with the drilling machine, for example in a situation in which the drilling machine is moving despite the absence of any corresponding movement controls.

[0008] Summary of the Invention

[0009] In accordance with a first aspect of the present invention, there is provided a safety system for a drilling machine that includes controllable drilling machine functions, the safety system comprising: a disparity checker arranged to carry out at least one functional disparity check to determine whether: a drilling machine function in the process of being implemented by the drilling machine has an associated drilling machine function instruction that correctly corresponds to the implemented drilling machine function; and / or a drilling machine function instruction provided to the drilling machine is in the process of being implemented at the drilling machine by implementing a drilling machine function, and the drilling machine function implemented at the drilling machine correctly corresponds to the drilling machine function instruction; the disparity checker arranged to generate disparity data if at least one disparity condition exists wherein the implemented drilling machine function does not have a corresponding drilling machine function instruction and / or the drilling machine function implemented at the drilling machine does not correctly correspond to the instructed drilling machine function; and at least one sensor usable by the disparity checker to carry out the functional disparity check; the system arranged to inhibit at least one drilling machine control in response to generation of the disparity data and based on defined disparity criteria.

[0010] In an embodiment, the system is arranged to instigate a hard shutdown of the drilling machine in response to defined disparity criteria, such as existence of the disparity condition for more than a defined period of time that may be at least 4s.

[0011] In an embodiment, the system is arranged to generate a communication indicative of the disparity condition.

[0012] In an embodiment, the system is arranged to facilitate cancellation of the disparity condition by an operator.

[0013] In an embodiment, the defined disparity criteria includes determination of a defined number of disparity conditions, such as 2 or 3 disparity conditions.

[0014] In an embodiment, the functional disparity check may be a disparity check to determine whether the drilling machine or a component of the drilling machine is disposed in an expected position or is moving in an expected way.

[0015] The disparity checker may comprise a tramming disparity checker arranged to carry out a tramming disparity check to determine whether the drilling machine or a component of the drilling machine is disposed in an expected position or is moving in an expected way. The tramming disparity checker may comprise a tramming disparity processor arranged to carry out the tramming disparity check.

[0016] In an embodiment, the functional disparity check may be a disparity check to determine whether the drilling machine is disposed in a defined orientation, such as a level orientation.

[0017] The disparity checker may comprise a levelling disparity checker arranged to carry out a levelling disparity check to determine whether the drilling machine is disposed in a defined orientation, such as a level orientation. The levelling disparity checker may comprise a levelling disparity processor arranged to carry out the levelling disparity check.

[0018] In an embodiment, the functional disparity check may be a disparity check to determine whether a drilling component of the drilling machine is operating in an expected way.

[0019] The disparity checker may comprise a drilling disparity checker arranged to carry out a drilling disparity check to determine whether the drilling machine is operating in an expected way. The drilling disparity checker may comprise a drilling disparity processor arranged to carry out the drilling disparity check.

[0020] In an embodiment, the disparity checker is arranged to use defined stored data, such as a defined setpoint, to carry out the at least one functional disparity check.

[0021] In an embodiment, the at least one sensor includes at least one position and / or movement sensor for determining the position and / or movement of the drilling machine. The position and / or movement sensor may include a GPS sensor.

[0022] In an embodiment, the at least one sensor includes at least one drilling machine position and / or movement sensor for determining the position and / or movement of the drilling machine. The position and / or movement sensor may include a GPS sensor.

[0023] In an embodiment, the at least one sensor includes at least one component position and / or movement sensor for determining the position and / or movement of a component of the drilling machine. In an embodiment, the at least one sensor includes at least one orientation sensor for determining an orientation of the drilling machine.

[0024] In an embodiment, the at least one sensor includes at least one control sensor arranged to determine the position and / or state of a control component.

[0025] In an embodiment, the at least one sensor includes at least one operational sensor arranged to determine an operational level of a component of the drilling machine. The operational level may include a pressure level of a component.

[0026] In an embodiment, the disparity checker uses a stored file to define the at least one functional disparity check. The stored file may comprise an XML file.

[0027] In an embodiment, the system comprises a supervisory PLC arranged to prevent implementation of at least one drilling machine function in response to generation of the disparity data and based on defined criteria.

[0028] In an embodiment, the system is arranged such that at least one defined disparity check is carried out based on defined criteria.

[0029] In an embodiment, the drilling machine has a plurality of associated machine states, and the system is arranged to carry out the at least one defined disparity check based on the machine state.

[0030] In accordance with a second aspect of the present invention, there is provided a method of managing safety of a drilling machine that includes controllable drilling machine functions, the method comprising: providing at least one sensor; carrying out at least one functional disparity check using the at least one sensor to determine whether: a drilling machine function in the process of being implemented by the drilling machine has an associated drilling machine function instruction that correctly corresponds to the implemented drilling machine function; and / or a drilling machine function instruction provided to the drilling machine is in the process of being implemented at the drilling machine by implementing a drilling machine function, and the drilling machine function implemented at the drilling machine correctly corresponds to the drilling machine function instruction; generating disparity data if at least one disparity condition exists wherein the implemented drilling machine function does not have a corresponding drilling machine function instruction and / or the drilling machine function implemented at the drilling machine does not correctly correspond to the instructed drilling machine function; and inhibiting at least one drilling machine control in response to generation of the disparity data and based on defined disparity criteria.

[0031] Brief Description of the Drawings

[0032] The present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0033] Figure 1 is a diagrammatic representation of an autonomous drilling arrangement;

[0034] Figure 2 is a schematic block diagram of functional components of a drilling machine that includes a safety system in accordance with an embodiment of the present invention;

[0035] Figure 3 is a schematic block diagram showing functional components of the safety system shown in Figure 2;

[0036] Figure 4 is a schematic block diagram showing disparity checking components of the safety system shown in Figures 2 and 3;

[0037] Figure 5 is an example xml file DisparityCheckHandler that defines a disparity checking process; and

[0038] Figure 6 is a flow diagram illustrating a method of managing safety of a drilling machine in accordance with an embodiment of the present invention.

[0039] Description of an Embodiment of the Invention The present invention relates to a safety system for an autonomous drilling arrangement, the safety system arranged to check for functional disparities associated with the drilling machine, for example whether a requested drilling machine function has been implemented by the drilling machine or whether a discrepancy exists between an implemented function and a requested function.

[0040] For example, the safety system may be arranged to check whether a drilling machine is moving in a manner that is expected, a levelling system of the drilling machine is operating as expected, and / or a drilling system of the drilling machine is operating as expected.

[0041] The safety system is independent of the drilling machine base control system.

[0042] Referring to the drawings, Figure 1 shows a diagrammatic representation of an example drilling arrangement 10 for an at least partially autonomously controlled drilling machine 12. According to the drilling arrangement 10, a drilling plan is implemented that defines a path of movement 14 for the drilling machine 12 relative to a target mining area 16 and the locations at which holes for receiving explosives will be drilled. In the present example, the drilling machines 12 are controlled from remote drill control stations 18 by defining movement plans at the drill control stations 18, for example through a wide area network such as the Internet 20 and a local mining area communications network 22. In an alternative arrangement, the drilling machines 12 may be manually controlled by an operator from a remote drill control location 18.

[0043] A representation of functional components of the drilling machine 12 is shown in Figure 2. In this example, the drilling machine functional components include a communications interface 24 arranged to facilitate communications between the drilling machine 12 and the local communications network 22, and drilling controls 26 arranged to instigate drilling machine functions 28, in this example according to a defined drilling plan.

[0044] The drilling controls 26 may include components that effect implementation of the drilling machine functions such as a control component arranged to send a signal to a track pump that effects movement of a drilling machine track based on the pressure produced by the pump. The drilling machine functions 28 may include: movement functions such as a tracking function associated with effecting movement of the drilling machine, and that implements movement of the drilling machine using drive components associated with machine tracks; levelling functions, such as associated with levelling jacks of the drilling machine, that effect extension and contraction of the levelling jacks in order to effect appropriate adjustment of the orientation of the drilling machine 12 prior to implementation of a drilling operation; and drilling functions associated with drilling operations, such as drill orientation and depth control functions.

[0045] The functional components of the drilling machine 12 also include a safety system 30 that carries out the checks for functional disparities associated with the drilling machine 12.

[0046] Example functional components of the safety system 30 are shown in Figure 3.

[0047] The functional components include at least one disparity checking component 32 arranged to carry out disparity checks to determine whether the drilling machine 12 is operating in an expected way or whether an error condition exists, such that for example the drilling machine is tracking in a way that is inconsistent with expectations. In this example, the disparity checking component 32 is implemented using at least one disparity processor arranged to carry out specific disparity checks based on data received from one or more sensors 33 and defined criteria.

[0048] The sensors 33 may include any arrangement that produces data indicative of the position, state and / or functionality of a component, such as the position of a component, or an operational level, such as a pressure level, of a component. As such, the sensors 33 are used to make determinations as to the status or performance of components of the drilling machine 12, so that comparisons can be made between actual and expected state or performance of the drilling machine 12.

[0049] The functional components also include a supervisory programmable logic controller (PLC) 34 that receives determinations made by the disparity checking component 32 and in response carries out actions to place the drilling machine in a safe condition, if necessary. In this example, the supervisory PLC 34 interfaces with a control neutraliser 36 arranged to deactivate the drilling controls 26 or a relevant selection of the drilling controls 36 in response to a determination by the disparity checking component 32 that an error condition exists, and a function inhibitor 38 arranged to prevent implementation of a drilling machine function in response to the determination by the disparity checking component 32 that the error condition exists.

[0050] In this example, the supervisory PLC 34 includes interfaces 40 arranged to enable the supervisory PLC 34 to communicate with the control neutraliser 36 and the function inhibitor 38, and to interface with the disparity processors 32. The supervisory PLC 34 also includes a processor 42, data storage 44 for storing programs 46 associated with the supervisory PLC 34 and a memory 48 usable by the supervisory PLC 34 to implement the desired functionality of the supervisory PLC 34.

[0051] In the event that a disparity condition remains after a defined period of time, such as 4s, the supervisory PLC 34 may be arranged to instigate a hard shutdown of the drilling machine 12.

[0052] It will be understood that placing the drilling machine 12 into a safe condition wherein drilling machine functions are inhibited and drilling controls are deactivated is preferable to effecting a hard shutdown of the drilling machine 12 because significantly more time is required to recover from a hard shutdown than a safe condition situation, and a hard shutdown causes more wear on the drilling machine than a safe condition situation.

[0053] The disparity condition is also communicated to a drill operator, for example by communicating information about the disparity condition to a drill control station 18. If the determined disparity condition is still present after a defined period of time, such as about 4s, the supervisory PLC 34 causes a hard shutdown of the drilling machine 12. If an operator considers that the safe state is not appropriate or no longer appropriate, the operator has the option to cancel the safe state, which causes the supervisory PLC 34 to re-activate the cancelled drill controls and cancel the inhibition of the relevant drilling machine functions. In the present example, the disparity processors 32 include a tramming disparity processor 52 arranged to carry out disparity checks associated with tramming functions of the drilling machine 12, a levelling disparity processor 54 arranged to carry out disparity checks associated with levelling functions of the drilling machine 12, and a drilling disparity processor 56 arranged to carry out disparity checks associated with drilling functions of the drilling machine 12. However, it will be understood that any suitable arrangement for implementing functional disparity checks is envisaged.

[0054] Each of the disparity processors 52, 54, 56 in this example includes associated programs 58a, b,c, memory 60a, b,c and interfaces 62a, b,c for carrying out the required functionality of the disparity processor 52, 54, 56.

[0055] Example disparity checking components that are used to carry out the disparity checks by the disparity processors 32 are shown in Figure 4. The disparity checking components include the sensors 33 that produce data indicative of the position, state and / or functionality of the drilling machine or component of the drilling machine, such as: a position of the drilling machine 12 or a component of the drilling machine 12; a state of a component such as a pressure level associated with a pump component; data indicative of the position or state of a drilling machine control component; and / or defined data associated with the drilling machine 12, such as defined set point values.

[0056] In the present example, the disparity checking components include tramming disparity components 64, drilling disparity components 80 and levelling disparity components 90.

[0057] In this example, the tramming disparity components 64 include a GPS device 66 that produces location and movement data indicative of the position of the drilling machine 12 and movement of the drilling machine 12; track controls 68 that produce data indicative of the position or state of a track control component such as whether the track control is in a forward, reverse or neutral position; and hydraulic pressure sensors 72 that sense hydraulic pressure associated with tramming pumps and produce data indicative of the pressure level of the tramming pumps.

[0058] Using the tramming disparity components 64, the tramming disparity processor 52 is for example able to determine a disparity associated with drilling machine tramming. For example, any one or more of the following tramming disparities may be checked: i) A disparity condition associated with a disparity between track control and GPS location. For example, if the GPS device indicates that movement of the drilling machine 12 is occurring but no corresponding movement signal associated with the track controls 68 exists, or the GPS device indicates that no movement exists or movement exists that is inconsistent with the track controls 68, a discrepancy may be generated. ii) A disparity condition associated with a disparity between track control and tramming hydraulic pressure. For example, if the hydraulic pressure sensors indicate that a positive pressure exists in a tramming pump but the track controls 68 do not indicate that a tramming movement has been instructed, or the hydraulic pressure sensors indicate that no pressure exists in a tramming pump but the track controls 68 indicate that a tramming movement has been instructed, a discrepancy may be generated. iii) A disparity condition associated with a disparity between track control and base machine setpoints.

[0059] In this example, the drilling disparity components 80 include drill setpoint data 82, pulldown control data 84 indicative of vertical movement of the drill bit of the drilling machine 12, and rotation control data 86 indicative of the speed of rotation of the drill bit.

[0060] Setpoint data 82 is data at the drilling machine 12 that is stored and used to for example control a component of the drilling machine 12, such as the drilling machine tracks, vertical movement of the drill bit or speed of rotation of the drill bit. The drilling machine 12 echoes the setpoint data 82 to the disparity checking components in response to receipt of a control signal, and a disparity between the setpoint data 82 and expectations indicates that an error condition exists.

[0061] Using the drilling disparity components 80, the drilling disparity processor 54 is able to determine whether a disparity exists between drill pulldown and rotation control data 84, 86 and associated setpoint data. In this example, the levelling disparity components 90 include drill levelling controls 92 that produce data indicative of the position or state of a drill levelling control component such as whether a left or right raise or lower control is active, and / or whether a front or rear raise or lower control is active; drill levelling sensors 94 that produce data indicative of the orientation of the drilling machine 12; jack controls 96 that produce data indicative of an instructed movement of a levelling jack to move to a raised position, a lowered position or a neutral position; jack position sensors 98 arranged to produce data indicative of the position of a levelling jack and whether the levelling jack is in a raised, lowered or neutral position; and jack pressure sensors 100 that produce data indicative of the pressure associated with the levelling jacks.

[0062] Using the levelling disparity components 90, the levelling disparity processor 56 is for example able to determine a disparity associated with drilling machine levelling. For example, any one or more of the following levelling disparities may be checked: i) A disparity condition associated with a disparity between jack controls associated with levelling jacks and levelling sensors. For example, the expected position and / or state of the jack controls may correspond to an expected orientation of the drilling machine 12 and this may be compared with a measured orientation obtained from the levelling sensors to determine whether a discrepancy exists. ii) A disparity condition associated with a disparity between levelling jack controls and levelling jack hydraulic pressures. For example, the position of the levelling jacks based on the data from the jack position sensors 98 and data derived from hydraulic pressure sensors associated with the levelling jacks may be used to determine whether a disparity exists. iii) A disparity condition associated with a disparity between levelling jack controls and base machine feedback. For example, the position of the levelling jacks based on the data from the jack controls and data derived from base machine sensors may be used to determine whether a disparity exists. iv) A disparity condition associated with a disparity between levelling jack controls and base machine setpoints. For example, the functionality of the levelling jacks based on the data from the jack controls and base machine setpoint data may be used to determine whether a disparity exists. v) A disparity condition wherein the jack pressure sensors 100 indicate that a positive pressure exists in a drill levelling jack but the jack controls 94 do not indicate that a jack raise or lower movement has been instructed.

[0063] The levelling disparity components 90 may also be arranged to carry out other disparity checks, such as whether the angle of a mast of the drilling machine 12 is appropriate using a mast angle sensor 102 that produces data indicative of the orientation of a mast of the drilling machine 12.

[0064] In this example, the disparity checking process is defined in an xml file, an example of which is shown in Figure 5, although it will be understood that any suitable arrangement for managing the disparity checking process is envisaged.

[0065] The example xml file 104 DisparityCheckHandler defines the number of different failures allowed at the same time, in this example 2 failures, so if 2 disparity checks associated with different disparity checks fail, a signal is sent to the supervisory PLC 34 to place the drilling machine in safe mode. The number of failures allowed for different individual disparity checking aspects of each of the tramming, levelling and drilling disparity checks before a signal is sent to the supervisory PLC 34 to place the drilling machine in safe mode are also defined. For example, 3 failures are allowed for a track pump pressure disparity check.

[0066] Referring to Figure 6, a flow diagram 120 illustrating steps 122 to 138 of a process for carrying out a discrepancy check and placing a drilling machine 12 into a safe condition is shown.

[0067] During operation of a drilling machine 12, a drilling plan is sent to the drilling machine 12 and the drilling machine 12 moves along a defined path associated with the drilling plan and drills holes at locations defined in the drilling plan.

[0068] As the drilling machine operates, the disparity processors 32 carry out disparity checks to determine whether any disparity condition exists based on the data associated with the tramming, drilling and levelling disparity components 64, 80, 90, and if a disparity condition is determined to exist a disparity signal is sent to the supervisory PLC 34, as indicated at steps 122 and 124, to put the drilling machine 12 into a safe state.

[0069] On receiving a disparity signal indicative of a disparity condition, the supervisory PLC 34 causes the function inhibitor 38 to inhibit at least the relevant drilling machine functions associated with the disparity condition and the control neutraliser 36 to deactivate at least the relevant drilling machine controls associated with the failed disparity check, as indicated at steps 126 and 128.

[0070] The disparity condition is also communicated to a drill operator, for example by communicating information about the disparity condition to a drill control station 18, as indicated at step 130.

[0071] As indicated at steps 132 and 134, if an operator considers that the safe state is not appropriate or no longer appropriate, the operator may cancel the safe state, for example using a drill control station 18, which causes the supervisory PLC 34 to reactivate the cancelled drill controls and cancel the inhibition of the relevant drilling machine functions.

[0072] As indicated at steps 136 and 138, if the determined disparity condition is still present after a defined period of time, such as about 4s, the supervisory PLC 34 causes a hard shutdown of the drilling machine 12.

[0073] The system may be arranged such that all disparity checks are always carried out when the drilling machine is operational, or such that defined disparity checks are carried out based on defined criteria, such as based on the operational state of the drilling machine. For example, the system may be arranged such that one or more defined disparity checks are associated with a machine state and only carried out when the machine is in the machine state. In a specific example, the system may be arranged such that when the drilling machine is in a tramming state, a pump pressure disparity check associated with tramming is carried out. Such a state specific disparity check is particularly useful for components such as pumps that are used for multiple drilling machine functions.

[0074] It will be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common general knowledge in the art, in Australia or any other country.

[0075] In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations such as “comprises” or “comprising” is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention. Modifications and variations as would be apparent to a skilled addressee are determined to be within the scope of the present invention.

Claims

BiThe claims defining the invention are as follows:

1. A safety system for a drilling machine that includes controllable drilling machine functions, the safety system comprising: a disparity checker arranged to carry out at least one functional disparity check to determine whether: a drilling machine function in the process of being implemented by the drilling machine has an associated drilling machine function instruction that correctly corresponds to the implemented drilling machine function; and / or a drilling machine function instruction provided to the drilling machine is in the process of being implemented at the drilling machine by implementing a drilling machine function, and the drilling machine function implemented at the drilling machine correctly corresponds to the drilling machine function instruction; the disparity checker arranged to generate disparity data if at least one disparity condition exists wherein the implemented drilling machine function does not have a corresponding drilling machine function instruction and / or the drilling machine function implemented at the drilling machine does not correctly correspond to the instructed drilling machine function; and at least one sensor usable by the disparity checker to carry out the functional disparity check; the system arranged to inhibit at least one drilling machine control in response to generation of the disparity data and based on defined disparity criteria.

2. A safety system as claimed in claim 1, wherein the system is arranged to instigate a hard shutdown of the drilling machine in response to defined disparity criteria.

3. A safety system as claimed in claim 2, wherein the system is arranged to instigate a hard shutdown of the drilling machine in response to existence of the disparity condition for more than a defined period of time.

4. A safety system as claimed in any one of the preceding claims, wherein the system is arranged to generate a communication indicative of the disparity condition.

5. A safety system as claimed in any one of the preceding claims, wherein thesystem is arranged to facilitate cancellation of the disparity condition by an operator.

6. A safety system as claimed in any one of the preceding claims, wherein the defined disparity criteria includes determination of a defined number of disparity conditions.

7. A safety system as claimed in any one of the preceding claims, wherein the functional disparity check comprises a disparity check to determine whether the drilling machine or a component of the drilling machine is disposed in an expected position or is moving in an expected way.

8. A safety system as claimed in any one of the preceding claims, wherein the disparity checker comprises a tramming disparity checker arranged to carry out a tramming disparity check to determine whether the drilling machine or a component of the drilling machine is disposed in an expected position or is moving in an expected way.

9. A safety system as claimed in claim 8, wherein the tramming disparity checker comprises a tramming disparity processor arranged to carry out the tramming disparity check.

10. A safety system as claimed in any one of the preceding claims, wherein the functional disparity check comprises a disparity check to determine whether the drilling machine is disposed in a defined orientation.

11. A safety system as claimed in claim 10, wherein the disparity checker comprises a levelling disparity checker arranged to carry out a levelling disparity check to determine whether the drilling machine is disposed in a defined orientation.

12. A safety system as claimed in claim 11, wherein the levelling disparity checker comprises a levelling disparity processor arranged to carry out the levelling disparity check.

13. A safety system as claimed in any one of the preceding claims, wherein the functional disparity check comprises a disparity check to determine whether a drillingcomponent of the drilling machine is operating in an expected way.

14. A safety system as claimed in claim 13, wherein the disparity checker comprises a drilling disparity checker arranged to carry out a drilling disparity check to determine whether the drilling machine is operating in an expected way.

15. A safety system as claimed in claim 14, wherein the drilling disparity checker comprises a drilling disparity processor arranged to carry out the drilling disparity check.

16. A safety system as claimed in any one of the preceding claims, wherein the disparity checker is arranged to use defined stored data to carry out the at least one functional disparity check.

17. A safety system as claimed in any one of the preceding claims, wherein the at least one sensor includes at least one position and / or movement sensor for determining the position and / or movement of the drilling machine.

18. A safety system as claimed in claim 17, wherein the position and / or movement sensor includes a GPS sensor.

19. A safety system as claimed in any one of the preceding claims, wherein the at least one sensor includes at least one component position and / or movement sensor for determining the position and / or movement of a component of the drilling machine.

20. A safety system as claimed in any one of the preceding claims, wherein the at least one sensor includes at least one orientation sensor for determining an orientation of the drilling machine.

21. A safety system as claimed in any one of the preceding claims, wherein the at least one sensor includes at least one control sensor arranged to determine the position and / or state of a control component.

22. A safety system as claimed in any one of the preceding claims, wherein the at least one sensor includes at least one operational sensor arranged to determine anoperational level of a component of the drilling machine.

23. A safety system as claimed in claim 22, wherein the operational level includes a pressure level of a component.

24. A safety system as claimed in any one of the preceding claims, wherein the disparity checker uses a stored file to define the at least one functional disparity check.

25. A safety system as claimed in any one of the preceding claims, wherein the system comprises a supervisory PLC arranged to prevent implementation of at least one drilling machine function in response to generation of the disparity data and based on defined criteria.

26. A safety system as claimed in any one of the preceding claims, wherein the system is arranged such that at least one defined disparity check is carried out based on defined criteria.

27. A safety system as claimed in claim 26, wherein the drilling machine has a plurality of associated machine states, and the system is arranged to carry out the at least one defined disparity check based on the machine state.

28. A method of managing safety of a drilling machine that includes controllable drilling machine functions, the method comprising: providing at least one sensor; carrying out at least one functional disparity check using the at least one sensor to determine whether: a drilling machine function in the process of being implemented by the drilling machine has an associated drilling machine function instruction that correctly corresponds to the implemented drilling machine function; and / or a drilling machine function instruction provided to the drilling machine is in the process of being implemented at the drilling machine by implementing a drilling machine function, and the drilling machine function implemented at the drilling machine correctly corresponds to the drilling machine function instruction; generating disparity data if at least one disparity condition exists wherein theimplemented drilling machine function does not have a corresponding drilling machine function instruction and / or the drilling machine function implemented at the drilling machine does not correctly correspond to the instructed drilling machine function; and inhibiting at least one drilling machine control in response to generation of the disparity data and based on defined disparity criteria.

29. A method as claimed in claim 28, comprising instigating a hard shutdown of the drilling machine in response to defined disparity criteria.

30. A method as claimed in claim 29, comprising instigating a hard shutdown of the drilling machine in response to existence of the disparity condition for more than a defined period of time.

31. A method as claimed in any one of claims 28 to 30, comprising generating a communication indicative of the disparity condition.

32. A method as claimed in any one of claims 28 to 31, comprising facilitating cancellation of the disparity condition by an operator.

33. A method as claimed in any one of claims 28 to 32, wherein the defined disparity criteria includes determination of a defined number of disparity conditions.

34. A method as claimed in any one of claims 28 to 33, wherein the functional disparity check comprises a disparity check to determine whether the drilling machine or a component of the drilling machine is disposed in an expected position or is moving in an expected way.

35. A method as claimed in any one of claims 28 to 34, wherein the functional disparity check comprises a tramming disparity check to determine whether the drilling machine or a component of the drilling machine is disposed in an expected position or is moving in an expected way.

36. A method as claimed in claim 35, wherein the tramming disparity check is carried out using a tramming disparity processor.

37. A method as claimed in any one of claims 28 to 36, wherein the functional disparity check is a levelling disparity check to determine whether the drilling machine is disposed in a defined orientation.

38. A method as claimed in claim 37, wherein the levelling disparity check is carried out using a levelling disparity processor.

39. A method as claimed in any one of claims 28 to 38, wherein the functional disparity check is a drilling disparity check to determine whether a drilling component of the drilling machine is operating in an expected way.

40. A method as claimed in claim 39, wherein the drilling disparity check is carried out using a drilling disparity processor.

41. A method as claimed in any one of claims 28 to 40, wherein the functional disparity check is carried out using defined stored data.

42. A method as claimed in any one of claims 28 to 41 , wherein the at least one sensor includes at least one position and / or movement sensor for determining the position and / or movement of the drilling machine.

43. A method as claimed in claim 42, wherein the position and / or movement sensor includes a GPS sensor.

44. A method as claimed in any one of claims 28 to 43, wherein the at least one sensor includes at least one component position and / or movement sensor for determining the position and / or movement of a component of the drilling machine.

45. A method as claimed in any one of claims 28 to 44, wherein the at least one sensor includes at least one orientation sensor for determining an orientation of the drilling machine.

46. A method as claimed in any one of claims 28 to 45, wherein the at least one sensor includes at least one control sensor arranged to determine the position and / or state of a control component.1147. A method as claimed in any one of claims 28 to 46, wherein the at least one sensor includes at least one operational sensor arranged to determine an operational level of a component of the drilling machine.

48. A method as claimed in claim 47, wherein the operational level includes a pressure level of a component.

49. A method as claimed in any one of claims 28 to 48, wherein the disparity check is carried out using a stored file to define the at least one functional disparity check.

50. A method as claimed in any one of claims 28 to 49, comprising using a supervisory PLC to prevent implementation of at least one drilling machine function in response to generation of the disparity data and based on defined criteria.

51. A method as claimed in any one of claims 28 to 50, comprising carrying out at least one defined disparity check based on defined criteria.

52. A method as claimed in claim 51, wherein the drilling machine has a plurality of associated machine states and the method comprises carrying out the at least one defined disparity check based on the machine state.

Images