Patent Application
20230228549
The present invention relates to wireless detonators, and more particularly to a magneto-inductive wireless detonator having a quantum receiver.
In the mining industry, conventional explosive detonation systems, commonly referred to as “detonators”, are generally of the electric type. Explosive charges are usually connected by means of cables to a firing system, which sends an electrical impulse, with or without delay, in order to optimize a firing plan.
A new “wireless” technology has emerged in recent years in the mining industry to optimize productivity and eliminate annoying cables. Importantly, however, while achieving its primary goal of eliminating cables, wireless technology currently in use has resulted in a significant negative collateral effect in connection with the security of operations.
There are currently two types of electronic detonators: wired and wireless. Wire detonators have two main advantages. They are extremely small and inexpensive to manufacture. On the other hand, they are very bulky, especially in mines underground, because they require a lot of winding. Hence the ever-growing industry interest in developing wireless detonators.
The current wireless detonators, called magneto-inductive, have a diameter much larger than wired detonators and they are much more expensive to manufacture. Moreover, since the diameter of the detonator is larger, the diameter of the bit, used to drill the hole to receive it, must have a directly proportional size. Consequently, the drilling process in the rock is automatically longer and more expensive.
These are the main reasons why these wireless detonators, which exist only for about five years and this without ever having, to our knowledge, been the subject of patents, are currently little used. At present, the use of the wireless detonator accounts for about 1% of the industry.
On the other hand, these magneto-inductive wireless detonators have some very important unique advantages: they are not connected to cables, they facilitate the search for metallic veins and they facilitate their own deployment.
We have designed a wireless detonator system based on the magneto-inductive principle which uses a low-frequency magnetic field to communicate with a transmitter within a radius of more than 1 square km buried up to several tens of meters in ground. Our design uses an ultra-miniature detonator, wireless, magneto-inductive, equipped with a diamond quantum radio, doped with nitrogen. This makes it possible to detect weak magnetic fields along all axes (X, Y and Z). The quantum radio is composed of a quantum receiver allowing the miniaturization of the wireless communication system. Indeed, the most recent discoveries in quantum electronics allow for new applications in the field of wireless detonators. Our design replaces conventional three bulky single-frequency antennae with a quantum receiver. This incorporates, on the one hand, an ultra-sensitive magnetic field measurement system (picotesla), based on the micro diamond doped with nitrogen, and, on the other hand, all the other usual functions of a wireless detonator system inside one or more integrated circuits. We can now manufacture detonators at low cost without magneto-inductive wires. This new quantum receiver technology makes it possible to reduce the diameters of the detonators, which improves productivity, particularly in the mining sector when searching for metal deposits. The multifrequency quantum receiver also makes it possible to correct an important problem of zone security for operators by adding a function for this purpose hitherto non-existent in wireless detonators.
Accordingly, in one embodiment there is provided a wireless detonator circuit comprising:
a nitrogen-doped diamond quantum receiver, the nitrogen being embedded inside a diamond substrate;
a light source for illuminating the nitrogen-doped diamond;
a plurality of layered optical filters are in communication with the light source;
one or more photodetector cells are located to measure the quantity of photons emitted by the light source; and
one or more microwave antennae are located to permit even polarization of the micro diamond, thereby permitting magnetic field detection sensitivity in the picotesla range.
In one example, the light source emits light in the red range and measures the intensity of photons emitted therefrom.
In one example, the light source is a light emitting diode or a laser diode.
In another example, the optical filters are a network of metallic conductors separated by a few nanometers, the filters eliminate residual photons at 532 nm,
In one example, the circuit further includes a second microwave excitation circuit is connected so as to control the detection frequency of the magneto-inductive signal.
In yet another example, the circuit further include a third ultra-sensitive circuit located to acquire data from the photodetector cells.
In one example, a digital filter located to permit digital demodulation to be performed on the magneto-inductive signal The digital filter is a Lock-In type digital filter.
In yet another example, a processing unit in communication with the digital filter, the processing unit allows decoding and activation of an explosive charge.
In another example, the circuit further includes a redundancy processing unit.
In another example, the circuit further includes one or more supply circuits.
In another example, the circuit further includes a communication circuit having an integrated ignition system.
In one example, a detonator that incorporates a multi-frequency quantum receiver.
In one example, a detonator which contains a zone protection system using a multi-frequency quantum receiver.
In still another example, the picotesla range is less than or equal to 10 picotesla.
In yet another example, the diamond is a micro diamond.
These and other features of that described herein will become more apparent from the following description in which reference is made to the appended drawings wherein:
Referring first to
To be effective, the antennae must be perfectly tuned using a capacitor which makes it possible to create a single frequency resonant circuit. This resonant circuit makes it possible to increase the sensitivity of the antenna to obtain a very narrow frequency response in order to eliminate the sources of surrounding noise produced mainly by the electrical networks (50/60 Hz and their harmonics). A variation, even very small, of the characteristics of the antenna or the capacitor creates a frequency shift of the resonant circuit and reduces the uniformity of the gain between the detonators. In a standard firing plan, we must be able to detonate several hundred detonators in a synchronized manner over an area of more than 1 square km and up to 30 meters deep in the ground. The communication times of magneto-inductive detonators are very long due to the preamble, which can be up to more or less about fifteen seconds, which must be added to the detonation programming. The electronic circuit of the detonator must select the best reception axis (choice of antenna X, Y or Z) by scanning in order to obtain the best signal integrity. This forces the transmitter to repeat its preamble sequence at least three times before activating the exchange of commands with the detonators. It is easy to understand that these repetitions lead to considerably increased risks of difficulties in synchronizing the communication with the detonators, thereby affecting the efficiency required during such operations.
Conventional wireless detonators also pose a major security problem for personnel. Given the long range of transmitters, these detonator systems are susceptible to harmful handling errors such as activation in another zone than that intended for the firing sequence.
For example, a firing plan can be planned within a radius of 1 km at 30 meters deep in the rock, but the signals can easily be picked up by mistake beyond this zone on the surface. An operator, or group of operators, could suffer a fatal accident if a detonator was activated in an area outside the intended area. In another example, detonators activated by mistake in a truck, in an area outside the firing plan, could explode accidentally. Finally, wireless detonators also have a definitely larger environmental footprint than standard electric detonators, due to their larger size (which generates waste plastic and metals such as copper and ferrite)
For all the above reasons, the mining industry seeks to reduce the size of its wireless detonators, which currently have a minimum diameter of around 3 cm.
Referring generally now to
Referring now more specifically to
Thus, in sum, our design provides a complete, fast, economical, ecological and security to the problems created both by traditional wired detonators and by the most recent current wireless detonators. This eliminates the very bulky nature of wired detonators while retaining their main advantages, their small format and their low manufacturing cost, thanks to miniaturization. Our design miniaturizes the current format of wireless detonators by reducing the diameter by 40 to 50% while maintaining their sensitivity (≤10 picotesla). This reduced diameter help obtain significant gains efficiency by reducing drill bit diameters and, by extension, drilling time. Furthermore, we have eliminated the axis antennae and replaced them with a quantum receiver. Moreover, our design eliminates the antenna selection process, thus improving the transmission time of information between the transmitter and the detonators by the fact that the quantum magnetometer is able to measure the magnetic field in all axes simultaneously. The significant time saving which design provides, also makes it possible, at choice, either to reduce the size of the battery integrated in the wireless detonator, or to increase its autonomy while maintaining the current size. Our design further reduces the diameter of the detonator by 40 to 50%, while maintaining its sensitivity (≤10 picotesla), making it possible to reduce the diameter of the boreholes necessary to insert the detonator. This in turn makes it possible to detect several frequencies simultaneously (multiple reception frequency) by merely modulating the excitation microwave field. Finally, the design uses the multi-frequency receiver, to enormously improve the safety of the process by giving the option of temporarily deactivating the detonator in certain zones when the quantum receiver detects a pattern of predetermined signals emitted by a short-range portable protection system. This then reduces by at least 50% the negative environmental footprint related to the manufacture and use of current wireless detonators which, due to their larger size and the materials of which they are made, generate garbage plastic and metals, such as copper and ferrite, in very large quantities.
From the foregoing description, it will be apparent to one of ordinary skill in the art that variations and modifications may be made to the embodiments described herein to adapt it to various usages and conditions.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CA2020/000085 | 6/3/2020 | WO |
