4. DESCRIPTION:
a. Statement of invention:
Robotic arm arrangement for autonomous blasthole mining cum tunneling machine.
b. Field of invention
The present invention relates to a device comprising of robotic arms for autonomously performing various operation for blasthole mining and tunneling. The robotic arms are arranged in a manner that can be used for blasthole drilling and explosive charging in an integrated manner.
c. Background of invention
Most of the current mining processes are performed using blasthole mining operation, in which a series of long holes (whose length and distribution depends on the hardness of the mineral rock being mined) called blast holes are drilled into the mineral rock using a drilling machine. Then the detonators are inserted into these holes followed by insertion of explosive cartridges. The processes of inserting detonators and explosives into the blast holes and making proper connections between these charged holes is called charging. Finally, this complete arrangement is detonated to give out various small rock fragments, which are eventually carried out of the tunnels/mines and subjected to further processing operations as applicable. In the current scenario, all these processes are manual in nature. Humans are performing all these operations- from drilling to explosive charging, making electrical connections amongst the detonators to exploding the system using appropriate hand tools. This consumes a lot of time making the production process too much slow. Further explosive handling requires high-grade labourers and has potential risks both in pre-charging and post-explosion durations.
Recently, a large number of inventions have accompanied this research area but in a practical sense, mining industry still remain away from the application of robotics and automation. Adrian et al [1] described about robotic explosive charging. This method charges explosives in blast holes drilled by some other drilling machine and the Robotic Explosive Charging System(RECS) function was divided into four basic functions namely detection of blast holes, tele-operated arm pose control, automatic arm pose control and human in the loop visual surveying. As drilling and charging are performed by two different machines, proper

identification of drilled blastholes remain a challenge for this system and so far have not addresses satisfactorily. Shaffer et al [2] discussed about the automation of a continuous miner machine. But application of continuous miner machine is limited to coal only due to its several limitations. Edlund et al invented drill automation control system [US005358058A] for blasthole mining operations. This system performs only drilling and require a separate charging device. Schweikart invented a method and apparatus for charging explosives [WO 2010144952 Al], but this system works well for open pit mines and surface mines only. Automatic explosive charging device of full-diameter colloid emulsion explosive charging machine was discussed in CN 201756515 U. This system also has limited applications inn underground mines and tunnels. Kullborg invented an automated connection system for a charging application and a charging method [WO 2017041820 Al]. This system uses detonating chord to initiate the detonators. Hummel et al invented wireless detonator assembly, and methods of blasting [US 7568429 B2]. All these inventions are only either drilling or charging and blasting platforms. References:
1. Adrian Bonchis, Elliot Duff, Jonathan Roberts, Mike Bosse, 'Robotic Explosive Charging in Mining and Construction Applications', IEEE Transactions On Automation Science and Engineering, Vol. 11, No. 1, January 2014, pp. 245- 250
2. Gary Shaffer, Anthony Stentz, 'A Robotic System for Underground Coal Mining', Proceedings of the 1996 IEEE International Conference on Robotics and Automation, Nice, France - May 1992, pp 633-638
Patent cited:

Cited Patent Patent title Filing date Publication date Inventor
[US005358058A] DRILL
AUTOMATION CONTROL SYSTEM Sep. 27, 1993 Oct. 25, 1994 Hans F. Edlund;
Marvin L. Haines
WO 2010144952 Al Method and apparatus for charging explosives Jun 15,2010 Dec 23,2010 Victor Schweikart
CN 201756515 U Automatic Jun 18,2010 Mar 9, 2011

explosive charging device of full-diameter colloid emulsion explosive charging machine

WO 2017041820 Al An automated connection system for a charging application and a charging
method Sep 7, 2015 Mar 16,2017 Camilla Kullborg
US 7568429 B2 Wireless detonator assembly, and methods of blasting 17 March 2006 4. Aug. 2009 Dirk Hummel, Michael J. McCann, Ronald F. Stewart
d. Objective of invention
The objective of the current invention is to perform blasthole drilling and explosive charging in an integrated and continuous manner to boost productivity as well as to reduce cost of production. Here all the three operations namely drilling, detonator charging and explosive charging need to be performed autonomously to exempt human workers from hazardous underground mine and tunnel environment.
e. Summary of invention
The proposed machine consists of a robotic bed where three different robotic arms mounted in a coordinated way, with each robotic arm performing a different function. The first robotic arm drills a series (pattern) of hole of required diameter in the rock/mineral ore while the second robotic arm takes out an electronic detonator from the vehicle container and inserts it

deep into the drilled hole. The third robotic arm acts the same way as the second one except that it places a much heavier explosive cartridge instead of detonator. The machine then after retracts to a safe distance and then detonates the charge, thus completing one cycle of operation. The pieces of rocks, so formed are removed transported as per the traditional transportation systems used in mines, f. Brief description of the prototype
The said invention has following components:
1. Robotic bed
2. Drill arm lead screw
3. Explosive arm lead screw
4. Detonator arm lead screw
5. Drill arm base
6. Explosive arm base
7. Detonator arm base
8. Drill arm vertical lead screw
9. Drill arm support

10. Drill arm top base
11. Drill arm feed link
12. Explosive arm link 2
13. Explosive arm link 3
14. Detonator arm link 2
15. Detonator arm link 3
16. Explosive gripper holder
17. Explosive gripper
18. Detonator gripper holder
19. Explosive arm pneumatic tube
20. Detonator arm pneumatic tube
21. Drill arm motor 1
22. Explosive arm motor 1
23. Detonator arm motor 1

24. Drill arm motor 2
25. Drill arm motor 3
26. Explosive arm motor 2
27. Explosive arm motor 3
28. Explosive arm motor 4
29. Detonator arm motor 2
30. Detonator arm motor 3
31. Detonator arm motor 4
32. Detonator gripper
The complete product assembly is shown in Figure 1 and Figure 2. Figure 1 and Figure 2 are two different views of the same assembly and show different components of the assembly. Robotic bed (1) consists of six holes, three on each side, to hold the three lead screws namely drill arm lead screw (2), explosive arm lead screw (3) and detonator arm lead screw(4). Robotic bed is shown in Figure 3. Further, robotic bed (1) has two slots to facilitate movement of pneumatic tubings (19 and 20) placed beneath the bed and there connected to a vacuum gripper cum compressor. There are five lead screws used in the proposed machine. Lead screw is shown in Figure 4. The first three lead screws [drill arm lead screw (2), explosive arm lead screw (3) and detonator arm lead screw(4) ] are mounted to the robotic bed (1) and act as the first link of each of the three robotic arms. Drilling arm lies on one extreme end and is named to be the first arm and numbering is done serially thereafter. Drill arm base (5) is mounted to the drill arm lead screw (2). Drill arm base (5) is shown in Figure 5 and consists of four holes, two for mounting it to the drill arm lead screw (2) and one each for holding a support pipe called drill arm support (9) and another lead screw called drill arm vertical lead screw(8). Drill arm support (9) is shown in Figure 8. Drill arm vertical lead screw(8) forms the second link of the drilling arm and is responsible for the Y- direction (vertical) motion of the drilling machine. Drill arm top base (10) is depicted in Figure 6 and consists of three cylindrical holes. Here two holes with parallel axis are there, one each for mounting it to the drill arm vertical lead screw(8) and the drill arm support (9), with the threaded one mating with the drill arm vertical lead screw(8). There is one more threaded hole in the perpendicular direction and houses the final link of the drilling arm called drill arm feed link(ll) . Drilling machine is mounted to the outer end of this drill arm feed link (11). Manipulator arm base is shown in Figure 7 and is used as explosive arm base (6) and detonator arm

base (7) in two separate instances. Explosive arm base (6) consisis of two coaxial holes that allow it to get mounted on the explosive arm lead screw (3) and also cons.sts of a protrusion to allow a motor (26) and explosive arm link 1(12) fix to it. Explosive arm base (6) has one more small hole to allow explosive arm pneumatic tubing (19) come out through it. Explosive arm base (6) is placed such that the slot in the robotic bed (1) is incorporated along the width of the explosive arm base (6). Detonator arm base (7) consists of two coaxial holes that allow it to get mounted on the detonator arm lead screw (4) and also consists of a protrusion to allow a motor (29) and detonator arm link 1(14) fix to it. Detonator arm base (7) has one more small hole to allow detonator arm pneumatic tubing (20) come out through it. Detonator arm base (7) is placed such that the slot in the robotic bed (1) is incorporated along the width of the detonator arm base (7). Explosive arm link 2 (12), explosive arm link 3 (13), detonator arm link 2 (14) and detonator arm link 3 (15) are shown in Figure 9, Figure 10, Figure 11 and Figure 12 respectively. All these links are rotary links and similar in construction with only difference being in their length. These links have triangulated type cross section to improve bending rigidity and to accommodate the flexible pneumatic tubing (19 and 20) inside it, preventing meshing up of rotary links (of detonator and explosive arm) with the tubings. Explosive arm pneumatic tube (19) comes out through the slot near explosive arm lead screw (3) and is routed towards the hole in explosive arm base(6). From there it enters the explosive arm link2 (12) and then to explosive arm link 3 (13) and finally enters the explosive gripper (17). Explosive gripper (17) is a vacuum gripper cup as shown in Figure 14 and is attached to explosive arm link 3 via Explosive gripper holder (16). Explosive gripper holder (16) is a vacuum gripper holder as shown in Figure 13 and has two ports - one to mount it to a motor and the other to hold the vacuum gripper cup. Detonator arm pneumatic tube (20) comes out through the slot near detonator arm lead screw (4) and is routed towards the hole in detonator arm base (7). From there it enters the detonator arm link2 (14) and then to detonator arm link 3 (15) and finally enters the detonator gripper (32). Detonator gripper (32) is a vacuum gripper cup as shown in Figure 14 and is attached to detonator arm link 3 via detonator gripper holder (18). Detonator gripper holder (18) is a vacuum gripper holder as shown in Figure 13 and has two ports - one to mount it to a motor and the other to hold the vacuum gripper cup. Flexible tubing (19 and 20) are connected via a compressor cum suction gripper and used for gripping the required explosive cartridges and detonators through a suction cup. Tubing are also used to blow air to the explosives and detonators to place it deep into the drilled hole. Three motors (21, 22 and 23) are placed in the inverted U type shell that forms a part of the robotic bed (1). These motors drive drill arm lead screw (2), explosive arm lead screw (3) and detonator arm lead screw(4)

and thus provide linear displacement to drill arm base (5), explosive arm base (6), detonator arm base (7). Motor (24) drives drill arm vertical lead screw and thus provide vertical motion to the drilling tool. Motor (25) provides feed to the drilling tool during drilling operation. Motor (26) actuates explosive arm link 2 (12) while motor (27) actuates explosive arm link 3 (13). Motor (28) helps in repositioning of explosive gripper (16) by properly orienting the explosive gripper holder (17) to face the drilled hole directly. Similarly, motor (29) actuates detonator arm link 2 (14) while motor (30) actuates explosive arm link 3 (15). Motor (31) helps in repositioning of detonator gripper (16) by properly orienting the detonator gripper holder (17) to face the drilled hole directly.
The proposed model consists of a robotic bed (1) housing robotic arms. Here the minimum number of robotic arms is two (at least one for drilling and one for detonator/explosive charging) and can be extended indefinitely based upon work requirement and restricted by working condition constraints. The robotic bed (1) housing all the robotic arms can be mounted over any vehicle chassis and preferably automated continuous tracked vehicle for better motion and traction. Here, lead screws (2,3,4,8,11) of all the robotic arms are actuated by DC servo motor (21,22,23,24,25) and the rotary links (12,13,14,15) are actuated by DC stepper motor (26,27,29,30). The end effector (16 & 17, 18 &32) motion is also rotary in nature and so is actuated by DC stepper motor (28,31). Further, all these DC motors are powered either by the electric cables available in the mines/tunnel or by electric battery -whichever is used to drive the vehicle containing this robotic bed. The vehicle housing this robotic bed must be able to remember its position in the three dimensional space and also to reorient itself in case of any misalignment.
Considering a three robotic arm model, the first arm (comprising of 2,5,8,9,10,11) is used for drilling blastholes, the third arm for charging the detonator into the drilled blastholes and the second arm (comprising of 3,6,12,13,16,17,19,26,27,28) for putting explosive cartridges in the holes already fitted with electronic detonators. The first arm (drilling arm) consists of all linear joints as each arm is a lead screw. The drilling machine is mounted at the outer end of drill arm feed link (11). Consider that the z-axis lies along the length of the drill arm lead screw (2), the y-axis along the height (depth) and x-axis perpendicular to the y-z plane. The rotation of the drill arm lead screw (2) gives the drill arm base (5) a motion in the Z-direction. In addition, the rotation of the drill arm vertical lead screw (8) gives the drilling arm a motion in the Y-direction. Here the actual drilling machine is mounted to the drill arm feed link(l 1), which is further supported by drill arm top base (10) engaged to the drill

arm vertical lead screw (8) and drill arm support (9). Here the drill arm support (9) performs an important function. It prevents the rotation (generated by principle of conservation of angular momentum) of drill arm top base (10) while the it is traversing upwards, thus making it easy to position the drill at point of the y-axis. The rotation of the drill arm feed link(ll) gives the drill arm base (5) a motion in the X-direction and is useful for providing feed during the drilling operation. Initially drill arm base (5), explosive arm base(6) and detonator arm base (7) - all are at zero lead screw position. The drilling arm starts the cycle of operation. It is to be noted here that the third arm, carrying detonator is the second in action. Explosive cartridges are charged only after the detonator has been inserted into the hole. Explosive cartridges and detonators are held by vacuum gripper action while being manipulated from their respective boxes to the mouth of the drilled blastholes. After placing the explosives cartridges/ detonators at the mouth of the drilled blastholes, vacuum gripper action ends and the pneumatic system switches on to a compressor. The compressor, then through the suction cup gives out a sufficient blow of air to gently push the explosive cartridge/ detonators to the end of the blasthole.
The direction of motion of robotic arms is divided into two - one along the direction of the lead screw and other along the transverse plane to the lead screw. Both types of motion may happen simultaneously in all the robotic arms. But when two or more robotic arms are at similarly parallel positions of the lead screw, motion in transverse direction is arrested to avoid collision. The explosive arm and the detonator arm take out explosive from the explosive box and detonator box respectively placed on one side of the robotic bed (on the detonator arm side of the robotic bed) and insert it into the blastholes drilled in mineral rock on other side of the robotic bed (on the drill arm side of the robotic bed).

5. CLAIMS:
We claim:
1. A flat bed (1) houses three different robotic arms - one of Cartesian configuration(2,5,8,9,l0,11,21,24,25) and rest two (3,6,12,13,16,17,19,22,26,27,28 and (4,7,14,15,18,20,23,29,30,3l,32)of hollow cylindrical configuration.
2. As claimed in claim 1, hollow cylindrical configuration is characterized by a first linear link (3 and 4)and two subsequent rotary links(12, 13 and 14,15).
3. As claimed in claim 2 the length of the second rotary link (13 and 15) for both the explosive and detonator arms is smaller than the first rotary link (12 and 14).
4. As claimed in claim 2 and 3, the range for the angular rotation of the 3rd link (13 and 15) with respect to the 2nd link (12 and 14) is restricted.
5. The flat bed as claimed in claim 1, includes a system to keep no arm functional in transverse direction at parallelly similar positions of various lead screws (2, 3, 4).
6. The flat bed as claimed in claim 1, includes a system to arrest rotation of arm base (5, 6, 7) by a flat bed (1) itself without making any other arrangement for arresting bed rotation.
7. A hollow triangulated section arrangement is made for tne rotary links (12, 13, 14, 15) that incorporates the flexible pneumatic tubing (19, 20) inside it and avoid meshing up of pneumatic tubing with robotic arms.
8. The flat bed as claimed in claim 1, includes a system to put the explosives cartridges and detonators deep in the drilled holes using gas/air supply from a compressor which comprises a vacuum gripper cup (17,32) connected to a pneumatic supply cum compressor.