Method of controlling a blasting system

Abstract

NOT VISIBLE DUE TO STATUS OF PATENT

Description

INT1616 / MAJRDETN1311METHOD OF CONTROLLING A BLASTING SYSTEMBACKGROUND OF THE INVENTION

[0001] The invention relates to a blasting system, and to a method of controlling the blasting system.

[0002] One form of a wireless blasting system includes a blasting machine in which is stored a blast plan, and which in use is located at a blast site, and a plurality of detonator assemblies which are responsive to a command signal transmitted via physical connections and / or wirelessly from the blasting machine, directly or via intermediate or relay devices, and which detonator assemblies are in use loaded into respective boreholes.

[0003] When blasting is desired, the blasting machine is operated to transmit a fire command signal to the detonator assemblies intended to be initiated, generally being all the detonator assemblies connected directly or indirectly to or otherwise within range of the blasting machine, which detonator assemblies in response to receiving the fire command are initiated.

[0004] It may be required to initially cause blasting at a predetermined area which is formed on the blast site before blasting another predetermined area on the blast site, in circumstances where both of those predetermined areas have been loaded with detonator assemblies and associated explosive materials.

[0005] It is often desirable to drill, load and charge multiple areas at the same blast site within the same cycle, to optimise the use of equipment, even where some areas are intended to be blasted in separate initiation events to others. Detonator assemblies may be loaded or programmed with information which enables them to identify, based on information included inINT1616 / MAJRDETN1312 a received command signal, whether that command signal is intended for them and whether they should, or should not, execute that command. Where the control of detonator assemblies is effected wirelessly, generally it is only practical to load or program them with information enabling them to determine whether a command signal is intended for them before they are deployed into the respective boreholes.

[0006] Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field.

[0007] However, as more information about the blast site becomes available after the deployment of the detonator assemblies into the respective boreholes, an operator may wish to change the blast plan by combining such areas for blasting or by selecting different combinations of areas to be blasted at respective times.An object of the present invention is to address at least to some extent the aforementioned situation.SUMMARY OF THE INVENTION

[0008] The invention provides a method of controlling a blasting system which includes a blasting machine which is operable to transmit via physical connections and / or wirelessly an encrypted command signal, directly or via intermediate or relay devices, to a plurality of detonator assemblies which are located at a blast site, the method including the steps of selecting a plurality of groups of detonator assemblies, providing each detonator assembly in each group with a respective group encryption key which is unique to the detonator assembliesINT1616 / MAJRDETN1313 in that group and which can be used to decrypt command signals encrypted with that same group encryption key (but not to decrypt command signals encrypted with any other encryption key), providing all the detonator assemblies in all groups deployed at the blast site with a universal encryption key, and using the blasting machine to transmit, directly or via intermediate relay devices, a transition command signal encrypted with the group encryption key for at least one selected group of detonator assemblies, which detonator assemblies in response to the transition command (once they have decrypted it using their group encryption key) are then configured to become responsive to a command signal which, prior to transmission by the blasting machine, is encrypted with the universal encryption key.

[0009] A tagger may be used to provide the respective group encryption key and the universal encryption key to each detonator assembly, such as by loading or programming each of those encryption keys into a memory component of each detonator assembly.

[0010] The transition command signal is, prior to transmission from the blasting machine, preferably encrypted with a group encryption key which corresponds with the group encryption key of the selected group of detonator assemblies.

[0011] Each group of detonator assemblies is, from the time of deployment into respective boreholes, responsive only to a command signal which is encrypted with the group encryption key of that group of detonator assemblies, and not to command signals encrypted with different encryption keys.

[0012] In one form of the invention, it is possible to select two or more groups of detonator assemblies to be combined into a combined group by using the blasting machine to successively send transition command signals which are encrypted with the respective group encryption keysINT1616 / MAJRDETN1314 of said selected groups of detonator assemblies thereby causing all of the selected groups of detonator assemblies to become responsive to a command signal which is encrypted with the universal encryption key.

[0013] The blasting machine may be used to transmit a revert command signal which is encrypted with the universal encryption key, thereby to cause each group of detonator assemblies of the combined group to become responsive only to a command signal which is encrypted with the respective group encryption key of that group of detonator assemblies.

[0014] A revert command signal transitions a respective state of each detonator assembly in the combined group of detonator assemblies to an initial state i.e. in which the detonator assembly is only responsive to a command signal which is encrypted with the group encryption key of the group to which the detonator assembly belongs.

[0015] A detonator assembly which misfires after receiving and successfully decrypting a fire command signal which is encrypted with the universal encryption key, is then preferably automatically configured to revert and become responsive only to a command signal which is encrypted with the detonator assembly’s group encryption key.

[0016] Each detonator assembly of the combined group of detonator assemblies which immediately following receipt and successful decryption of a fire command signal encrypted with the universal encryption key, is misfired is preferably configured to revert to a condition in which the detonator assembly is responsive only to a command signal which is encrypted with the group encryption key of the group to which the detonator assembly belongs. This provides a measure of safety as the misfired detonator assemblies are inhibited from detonating uponINT1616 / MAJRDETN1315 receiving and successfully decrypting a subsequent command signal to fire which is encrypted with the universal encryption key.

[0017] The invention further extends to a blasting system which includes a blasting machine which is operable to transmit via physical connections and / or wirelessly an encrypted command signal, directly or via intermediate or relay devices, to a plurality of groups of detonator assemblies which are located at a blast site, each group of detonator assemblies having a respective group encryption key which is unique to that group loaded onto each detonator assembly of that group, each detonator assembly having a universal encryption key loaded onto the detonator assembly, and wherein each of at least one selected group of detonator assemblies is configured to become responsive to a command signal which is encrypted with the universal encryption key upon receipt and successful decryption of a transition command signal from the blasting machine which is encrypted with the respective group encryption key of the selected group.

[0018] All the detonator assemblies of each group are preferably provided with the respective group encryption key and the universal encryption key by means of a tagger, such as by loading or programming each of those encryption keys into a memory component of each detonator assembly.

[0019] The groups of detonator assemblies may be positioned at respective blast areas which do not overlap with each other on the blast site.

[0020] Each group of detonator assemblies is preferably responsive only to a command signal which is encrypted with the respective group encryption key of that group of detonator assemblies, prior to receiving and successfully decrypting the transition command signal.INT1616 / MAJRDETN1316

[0021] Two or more selected groups of detonator assemblies may be combined into a combined group of detonator assemblies upon receipt and successful decryption by each group of said selected groups of detonator assemblies of a transition command signal which is encrypted with the respective group encryption key of that group of detonator assemblies, each of which is transmitted successively by the blasting machine, thereby causing all of the groups of detonator assemblies of the combined group to become responsive to a command signal which is encrypted with the universal encryption key.

[0022] The blasting machine may be operable to transmit a revert command signal which is encrypted with the universal encryption key, and each group of detonator assemblies of the combined group may be configured to become responsive only to a command signal which is encrypted with the respective group encryption key of that group of detonator assemblies in response to receiving and successfully decrypting the revert command signal which is encrypted with the universal encryption key.

[0023] A detonator assembly which misfires after receiving and successfully decrypting a fire command signal which is encrypted with the universal encryption key may automatically be configured to be responsive only to a command signal which is encrypted with the detonator assembly’s group encryption key.BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The invention is further described by way of example with reference to the accompanying drawings in which:INT1616 / MAJRDETN1317

[0025] Figure 1 schematically illustrates, in plan, a blasting system which includes a blasting machine, a plurality of detonator assemblies which are located in respective boreholes, and which have been divided into groups of detonator assemblies, according to the invention;

[0026] Figure 2 is a side view, in cross section, of one of the detonator assemblies which is located in a borehole shown in Figure 1 ;

[0027] Figure 2A shows in block diagram format a portion of the detonator assembly which is encircled in dotted outline marked “A” in Figure 2;

[0028] Figure 3 schematically depicts, in plan, the blasting system shown in Figure 1 with two groups of detonator assemblies being selected to respond to a command signal from the blasting machine; and

[0029] Figure 4 shows in block diagram format steps which are required to perform the principles of the invention.DESCRIPTION OF PREFERRED EMBODIMENT

[0030] Figure 1 schematically illustrates, in plan, a blasting system 10 which includes a blasting machine 12, and a plurality of detonator assemblies 14 which are located in respective boreholes 16, and which have been divided into a plurality of groups 18 of detonator assemblies 14, according to the invention.

[0031] The blasting machine 12 is operable to transmit an encrypted command signal 20 to the plurality of groups 18 of detonator assemblies 14. The encrypted command signal 20 can be one of an arm command signal, a fire command signal, a transition command signal, a revert command signal, or the like. The invention is not limited in this respect.INT1616 / MAJRDETN1318

[0032] The boreholes 16 are formed at a blast site 22. Each group 18 of detonator assemblies 14 is positioned in a respective area 24 which comprises a portion of the blast site 22.

[0033] Each group 18 of detonator assemblies 14 has a respective group encryption key which is unique to that group 18. The group encryption key is loaded onto each detonator assembly 14 of that group 18. A universal encryption key is loaded onto all the detonator assemblies 14 of all the groups 18.

[0034] Each detonator assembly 14 of at least one selected group 18 of detonator assemblies 14 is configured to become responsive to a command signal 20 which is encrypted with the universal encryption key upon receipt and successful decryption of a transition command signal 20 from the blasting machine 12 which is encrypted with the respective group encryption key of the selected group 18.

[0035] Figure 2 is a side view, in cross section, of one of the detonator assemblies 14, which is loaded in a borehole 16, shown in Figure 1. The detonator assembly 14 comprises an initiator 26 which is located in the borehole 16, and a top box 28 which is connected via a wire 29 to the initiator 26.

[0036] Figure 2A shows in block diagram format components of the top box 28, which is encircled in dotted outline marked “A” in Figure 2.

[0037] The top box 28 includes a transceiver 30 which is capable of receiving and decrypting wireless command signals 20 from the blasting machine 12, and which is capable of transmitting wireless response signals to the blasting machine 12, a processor 32 which is associated with the transceiver 30, a memory module 34 which is connected to the processor 32 and a power source 36 which powers the transceiver 30 and the processor 32.INT1616 / MAJRDETN 1319

[0038] In another form of the invention, not shown, all of the components of the detonator assembly 14 i.e. the initiator 26, the transceiver 30, the processor 32, the memory module 34 and the power source 36 are located in a single unit, which may comprise more than one housing. In this form of the invention, the unit is located inside the borehole 16, and the transceiver 30 is capable of receiving and decrypting through the earth (TTE) command signals 20 from the blasting machine 12, e.g. through the use of magnetic induction.

[0039] A tagger 38 is used by a user, not shown, to load the respective group encryption key onto the memory modules 34 of all the detonator assemblies 14 of each group 18 of detonator assemblies 14 and to load the universal encryption key onto the memory modules 34 of all the detonator assemblies 14 of the blasting system 10, prior to loading the detonator assemblies 14 into the respective boreholes 16. The tagger 38 is used to provide the detonator assemblies 14 with the group encryption keys and the universal encryption keys.

[0040] Each group 18 of detonator assemblies 14 is initially responsive only to a command signal 20 which is encrypted with the respective group encryption key of that group 18 of detonator assemblies 14, prior to receiving and decrypting a transition command signal. The arrangement is such that, prior to receiving and decrypting the transition command, the respective transceiver 30 of each detonator assembly 14 is capable of receiving and decrypting a command signal 20 which is encrypted with either a group encryption key or the universal encryption key. However the respective processor 30 is enabled only to process the command signal 20 if the command signal is encrypted with a group encryption key which corresponds with the group encryption key which is loaded onto the respective memory module 34.INT1616 / MAJRDETN13110

[0041] The respective processor 30 of each detonator assembly 14 is configured to become responsive to a command signal 20 which is encrypted with the universal encryption key upon receipt and successful decryption by the respective transceiver 30 of a transition command signal which is encrypted with the group encryption key which corresponds with the group encryption key which is loaded onto the respective memory module 34.

[0042] Figure 3 schematically depicts, in plan, the blasting system 10 shown in Figure 1 with two groups 18, marked as A and B, of detonator assemblies 14 being selected to respond to a command signal 20 from the blasting machine 12.

[0043] Figure 4 shows in block diagram format steps which are required to perform the principles of the invention.

[0044] It is possible to combine two or more groups 18 of detonator assemblies 14, marked A, B, and C in Figure 3 into a combined group 40 of detonator assemblies 14. This is achieved by selecting (42) the groups 18 which are desired to be combined, say groups A and B, and operating the blasting machine 12 to transmit, in succession, transition command signals (44), each of which is encrypted with the respective group encryption key of one of the selected groups A and B to all the groups 18 of detonator assemblies 14. For example if the blasting machine 12 is used to first send a transition command signal 20 which is encrypted with the group encryption key of group A, the respective transceivers 30 of all the detonator assemblies 14 of all the groups 18 receive and decrypt the transition command signal 20, but as only the respective processors 32 of group A are enabled to process the transition command 20, only the detonator assemblies 14 of group A are transitioned. The blasting machine 12 is then used to transmit a second transition command signal 20 which is encrypted with the group encryption key of group BINT1616 / MAJRDETN13111 thereby causing the detonator assemblies 14 of group B to transition. It is possible to repeat this process until all the groups 18 which are selected to be combined have transitioned.

[0045] The combined group 40, which in this non-limiting example comprises groups A and B, is then responsive to a command signal 20 which is encrypted with the universal encryption key. The blasting machine 12 can then be operated to transmit a command signal 20 which is encrypted with the universal encryption key, e.g. a fire command signal 20, to cause only the detonator assemblies 14 of the combined group 40 (A, B) to execute an action based on the command signal 20. In the case where the command signal is a fire command signal 20, all the detonator assemblies 14 of the combined group 40 (A, B) in response to receiving and successfully decrypting and processing the command signal 20 are caused to initiate thereby effecting a blast.

[0046] If the blast is to be aborted, the blasting machine 12 is operated to transmit a revert command signal (46) which is encrypted with the universal encryption key, which causes each group 18 of detonator assemblies 14 of the combined group 40 (A, B) to become responsive only to a command signal 20 which is encrypted with the detonator assembly’s 14 group encryption key.

[0047] A detonator assembly 14 which misfires after receiving and successfully decrypting a fire command signal (48) which is encrypted with the universal encryption key is configured to automatically become responsive only to a command signal 20 which is encrypted with the detonator assembly’s 14 group encryption key thereby to place the detonator assembly 14 in a safe state 50. This ensures that after the combined group 40 of detonator assemblies 14 has been instructed to initiate by using the blasting machine 12 to transmit a fire command signal 20INT1616 / MAJRDETN13112 using the universal encryption key, and if one of said detonator assemblies 14 has not initiated, then that detonator assembly 14 is automatically restored to the mode in which it can only be fired by a signal with the group encryption key, so as not to be inadvertently initiated when a next combined group 40 (A, B) of detonator assemblies 14 is initiated.

[0048] The abovementioned process is repeated until all the groups 18 of detonator assemblies 14 have been initiated.

[0049] By employing the principles of the invention, it is possible for the operator to select combinations of areas at the blast site for blasting at respective times which are different from one another.

[0050] Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise”, “comprising”, and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”.

Claims

INT1616 / MAJRDETN13113CLAIMS1. A method of controlling a blasting system which includes a blasting machine which is operable to transmit an encrypted command signal to a plurality of detonator assemblies which are located at a blast site, the method including the steps of selecting a plurality of groups of detonator assemblies, providing each detonator assembly in each group with a respective group encryption key which is unique to the detonator assemblies in that group, providing all the detonators with a universal encryption key, and using the blasting machine to transmit a transition command signal encrypted with the group encryption key for at least one selected group of detonator assemblies, which detonator assemblies in response to the transition command are then configured to become responsive to a command signal which is encrypted with the universal encryption key.

2. The method of controlling a blasting system according to claim 1 which includes the step of using a tagger to provide the respective group encryption key and the universal encryption key to each detonator assembly in each group.

3. The method of controlling a blasting system according to claim 1 which includes the step of encrypting the transition command signal, prior to transmission from the blasting machine, with a group encryption key which corresponds with the group encryption key of the selected group of detonator assemblies.

4. The method of controlling a blasting system according to claim 1 which includes the step of selecting two or more groups of detonator assemblies to be combined into a combined group by using the blasting machine to successively send transition command signals which are encrypted with the respective group encryption keys of said selected groups ofINT1616 / MAJRDETN13114 detonator assemblies thereby causing all of the selected groups of detonator assemblies to become responsive to a command signal which is encrypted with the universal encryption key.

5. The method of controlling a blasting system according to claim 4 which includes the step of using the blasting machine to transmit a revert command signal which is encrypted with the universal encryption key, thereby to cause each group of detonator assemblies of the combined group to become responsive only to a command signal which is encrypted with the respective group encryption key of that group of detonator assemblies.

6. The method of controlling a blasting system according to claim 1 which includes the step of reverting all detonator assemblies which misfire after receiving and successfully decrypting a fire command signal which is encrypted with the universal encryption key, such that each of said detonator assemblies become responsive only to a command signal which is encrypted with the group encryption key of the group of that detonator assembly.

7. The method of controlling a blasting system according to claim 4 which includes the step of reverting each detonator assembly of the combined group of detonator assemblies which immediately following receipt and successful decryption of a fire command signal encrypted with the universal encryption key, to a condition in which the detonator assembly is responsive only to a command signal which is encrypted with the group encryption key of the group to which the detonator assembly belongs.

8. A blasting system which includes a blasting machine which is operable to transmit an encrypted command signal to a plurality of groups of detonator assemblies which are located at a blast site, each group of detonator assemblies having a respective groupINT1616 / MAJRDETN13115 encryption key which is unique to that group loaded onto each detonator assembly of that group, each detonator assembly having a universal encryption key loaded onto the detonator assembly, and wherein each of at least one selected group of detonator assemblies is configured to become responsive to a command signal which is encrypted with the universal encryption key upon receipt of a transition command signal from the blasting machine which is encrypted with the respective group encryption key of the selected group.

9. The blasting system according to claim 8 wherein all the detonator assemblies of each group are provided with the respective group encryption key and the universal encryption key by means of a tagger.

10. The blasting system according to claim 8 wherein the groups of detonator assemblies are positioned at respective blast areas which do not physically overlap with each other on the blast site.11 . The blasting system according to claim 8 wherein each group of detonator assemblies is responsive only to a command signal which is encrypted with the respective group encryption key of that group of detonator assemblies, prior to receiving and successfully decrypting the transition command signal.

12. The blasting system according to claim 8 wherein two or more selected groups of detonator assemblies are combined into a combined group of detonator assemblies upon receipt and successful decryption by each group of said selected groups of detonator assemblies of a transition command signal which is encrypted with the respective group encryption key of that group of detonator assemblies, each transition command being transmitted successively by the blasting machine, thereby to cause all of the groups ofINT1616 / MAJRDETN13116 detonator assemblies of the combined group to become responsive to a command signal which is encrypted with the universal encryption key.

13. The blasting system according to claim 12 wherein the blasting machine is operable to transmit a revert command signal which is encrypted with the universal encryption key, and each group of detonator assemblies of the combined group is configured to become responsive only to a command signal which is encrypted with the respective group encryption key of that group of detonator assemblies in response to receiving and successfully decrypting the revert command signal.

14. The blasting system according to claim 8 wherein each detonator assembly which misfires after receiving and successfully decrypting a fire command signal which is encrypted with the universal encryption key is automatically configured to be responsive only to a command signal which is encrypted with the detonator assembly’s group encryption key.