Humanitarian Demining Part 12 potx

Land Robotic Vehicles for Demining 321 - External detection and sensory systems for sensing / monitoring environment (global position sensing – GPS, multi- sensorial mine detection / recognition systems, vehicle navigation, obstacles, etc.) - Sophisticated communication and control systems. The vehicle control system includes navigation and mobility control. As regards to navigation the vehicle operates within the global world coordinates measured by GPS or within local references defined on place. Control of robot arm is considered to be in local world or tool reference coordinates. Global control scheme of the system shows Fig.5. - An operation / control center with monitoring devices. Fig. 5 . Global control scheme of the robotic vehicle for demining operations 4. Further Development of Demining Machines 4.1 Design and System Description As discussed in (Havlik, 2007) there are several criteria should be taken into account and standards (CEN, 2004) that any vehicle for mechanical demining should satisfy. On the example of Božena machines further research and development of vehicles with mechanical activation technology is shown. “Božena 4” in Fig. 6, is the fourth generation of the mini-flail vehicles mainly oriented for clearing large areas from antipersonnel mines (AP) as well as from anti-tank (AT) mines up to 9 kg of TNT equivalent. The last generation machine of this family, “Božena 5”, belongs to category of midi-flail systems. This much more powerful machine exhibits about two-times higher productivity of Multisensorial p erceptionand recognition systemfor landmine detection - manipulator - robot - gun - marking system- Servo drivers for steering ENVIRONMENT OPERATION CENTER Tools Navigation - position control - collision avoidance, Target positioning Tools, robot, manipulator, Sensors for vehicle and tools control GPS / local position Minefield, world coordinates, camera, Local / vehicle coordinatesGlobal / field coordinates Humanitarian Demining: Innovative Solutions and the Challenges of Technology 322 cleaning comparable terrains. To reach a good maneuvering capability in various terrains the solution that enables to combine wheels and belts was adopted. Fig. 6. Božena 4 (left) and Božena 5 (right) in demining action Control of all mechanisms is realized from the cabin where all data and information about the machine and its environment are transmitted. The operator can use the special portable control box with keyboard and joystick. Some principal control routines are pre- programmed. To improve controllability of vehicle actions the on-board remote vision system has been developed and can be installed. In the most complex configuration it consists of two stable cameras for observation the environment in front and in rear of the vehicle and one camera fixed on the 2 d.o.f. mechanism, in Fig. 7., which enables adjustable possibility of observation within the whole area 360 0 around the vehicle and +/- 20 0 tilting. Pictures from cameras are digitally transmitted on screens into the operation center. Thus, combining the visual pictures with GPS data it is possible to recognize actual situation on the minefield (terrain, obstacles, trenches, trees, etc.) and to make correct decisions. Fig. 7. The robust camera and monitor box of the vision system In cases when the vehicle can not move due to any serious failures (engine, communication, etc.) it should be removed from the minefield. For this purpose it is equipped by the hydraulic winch - cable mechanism. This simple recovery system enables the machine to be pulled back from a dangerous place. Land Robotic Vehicles for Demining 323 4.2 Tools and Attachments Concept of the multi-purpose machine includes two categories of tools and attachments. There are: - Equipment directly related to the demining process: platform for detection systems, flailing mechanism, target marking system, saw / cutter of vegetation, system for removing metal parts, grippers, etc. - Equipment for engineering works as digging, drilling, loading and transport of soil or loose materials, removing obstacles, etc. Some examples of these accessories have been developed for Božena machines are given in next. Flailing Mechanism The well known flailing principle consists of the rotating shaft with set of chains and hammers on their ends. The crucial problem is to design such a flailing system which keeps maximal efficiency and quality together with high productivity of cleaning process. To achieve this performance many parameters and characteristics should be studied and experimentally verified. Some of them are: length of chains, forms and material of hammers, positions of chains on the shaft, speed of rotation, impact energy of hammers, advance speed with respect to depth of penetration, soil, etc. Beside technical criteria, the mechanism should be very robust to resist explosions of AP mines and possible AT mines too. The flailing mechanism in Fig. 8 is designed as an independent system powered by two hydro-motors with reverse rotation possibility. The flailing process, including advance speed, shaft rotation speed, depth, copying the terrain, is fully controlled by pre programmed routines. Fig. 8. Flailing mechanism Collector of Magnetic Parts After cleaning process on each minefield are usually spread great numbers of metal parts, such as shells, ammunition cartridges, mine fragments, or other ferromagnetic parts such as wires, screws, etc. Obviously, these spread parts result in false signals of metal detectors when the verification procedure is doing. To pick up all small ferromagnetic parts the special attachment -magnetic collector, in Fig.9, is designed. Humanitarian Demining: Innovative Solutions and the Challenges of Technology 324 Fig. 9. Magnetic collector Soil Separator Another useful attachment is the mechanism for sifting and recycling soils where AP mines and UXO are expected. This attachment enables to take up the material (soil, waste) and, after closing the drum, by turning motion the content is sifted. The objects, as AP mines, remain inside the drum and may be dumped afterwards after opening the jaw. Grated form of jaws is as well the best solution enables to spread the blast wave in case explosions inside the drum. As the procedure is remotely controlled the safety for operator is provided. Fig. 10. Separator for sifting and recycling soil Other Attachments Beside direct demining process, there are many dangerous works should be made in remote operation mode. Main reason is to protect persons if any suspicion on explosion or other possible hazard situation could arise. There are several useful accessories that can be directly attached on the end flange of the heavy load manipulator. Some of them frequently applied for most principal works are in Fig.11. Land Robotic Vehicles for Demining 325 Fig. 11. Some accessories for remotely operated machines 5. Conclusion Considering large polluted areas and drawbacks of actual demining technologies main contributions of using robotic vehicles are expected in following topics: − Searching large areas and localization of mines and any explosives (UXO) by fast and reliable way. − Fast and reliable neutralization/destruction of mines without the need of personal assistance to be inside, or close to dangerous places. Demining process remains and will be still one of the most dangerous operations. For this reason new robotic technologies and detection principles should be applied. The paper presents a modular concept and on examples describes the robotic vehicles equipped by the flailing activation mechanism and other accessories used in demining process and other civil engineering works. All activities in dangerous terrains, as minefields, require applying specific approaches to searching, precise localization of single targets, neutralization process and other works, as well. Operations of unmanned vehicles in such terrains suppose that they have some level of autonomy to solve especially critical situations. This is the task for research in the future. Humanitarian Demining: Innovative Solutions and the Challenges of Technology 326 Acknowledgment Author highly appreciates the help of the WAY industry company – Slovakia (www.wayindustry.sk) and will express thanks for information and photo-material used in this article. 6. References GICHD (2006). Mechanical demining equipment catalogue. Geneva Int. Center for Humanitarian Demining. (www.gichd.ch), March 2006, ISBN 2-88487-026-1 GICHD (2004). A study of mechanical application in demining. Geneva Int. Center for Humanitarian Demining. www.gichd.ch, May 2006, ISBN 2-88487-023-7 CEN (2004). Workshop Agreement „Test and evaluation of demining machines.“ CWA 150 44, July 2004, Proc. (2007). Proc. on the 4th International Symposium “Humanitarian Demining 2007 – Mechanical Demining” 24 - 27 April, Šibenik, Croatia. (to be published in 2007) Habib, M.K. (2002). Mechanical mine clearance technologies and humanitarian demining. Applicability and Effectiveness. In Proc. 5 th. Int. Symposium on Technology and mine problem. Monterey, CA, USA Apr. 22-25. pp. Havlík, Š. (2005). A modular concept of robotic vehicle for demining operations. Autonomous Robots, 18, 2005, pp. 253 – 262 Havlík Š. (2007). Some robotic approaches and technologies for humanitarian demining. Publ. in this book. Ide, K. et al. (2004). Towards a semi -autonomous vehicle for mine neutralization. In Proc. International Workshop Robotics and Mechanical assistance in Humanitarian Demining and Similar risky interventions, IARP, Brussels-Leuven, Belgium, June 16-18. Kaminski, L. et al. (2003). The GICHD Mechanical Application in Mine Clearance Study. Proc. EUDEM2-SCOT –2003 Int. Conf. on Requirements and Technologies for Detection, Removal and Neutralization of Landmines and UXO. Sept. 15-18, Brussel, Belgium, pp.335-341 Licko, P. & Havlik, S. 1997. The demining flail and system BOZENA. In Proc. International Workshop on Sustainable Humanitarian Demining, SUSDEM 97, Zagreb, Croatia, Sept. 29 – Oct. 1, pp. S4.8-S.4.11. Lindman, A.R. & Watts, K.A. (2003). Inexpensive mine clearance flails for clearance of anti- personnel mines. In Proc. EUDEM2-SCOT–2003 Int. Conf. on Requirements and Technologies for Detection, Removal and Neutralization of Landmines and UXO, Brussels, Belgium, Sept. 15-18, pp.356-359. Stilling, D.S.D., Kushwaha, R.L. & Shankhla, V.S. (2003). Performance of chain flails and related soil interaction. In Proc. EUDEM2-SCOT –2003 Int. Conf. on Requirements and Technologies for Detection, Removal and Neutralization of Landmines and UXO. , Brussels, Belgium, Sept. 15-18, pp.349-355. WAY Industry, a.s. (2006). Technical specifications of mine clearance flail systems: BOZENA 4, 5; WAY Industry, a.s., Slovakia 14 PEACE: An Excavation-Type Demining Robot for Anti-Personnel Mines Yoshikazu Mori Ibaraki University Japan 1. Introduction We propose an excavation-type demining robot PEACE for farmland aiming at “complete removal” and “automation.”(Mori et al., 2003, Mori et al., 2005) The reason why we choose farmland as the demining area is as follows: farmland is such an area where local people cannot help entering to live, so it should be given the highest priority (Jimbo, 1997). PEACE is designed to clear APMs (anti-personnel mines) after disposing ATMs (anti-tank mines) and UXOs (unexploded ordnances). Needless to say, the first keyword “complete removal” is inevitable and is the most important. The second one “automation” has two meanings, that is, safety and efficiency. In the conventional research, detection and removal of mines are considered as different works, and the removal is after the detection. However, in the case of the excavation-type demining robot, detecting work will be omitted because the robot disposes of all mines in the target area. As the result, no error caused in the detecting work brings the demining rate near to 100%. Currently, the demining work mainly depends on hazardous manual removal by humans; it presents serious safety and efficiency issues. For increased safety and efficiency, some large- sized machines have been developed. For example, the German MgM Rotar rotates a cylindrical cage attached in front of the body and separates mines from soil (see Fig. 1, Geneva International Centre for Humanitarian Demining, 2002; Shibata, 2001). The RHINO Earth Tiller, also made in Germany, has a large-sized rotor in front of the body; it crushes mines while tilling soil (see Fig. 2, Geneva International Centre for Humanitarian Demining, 2006). The advantages of MgM Rotar and RHINO are a high clearance capability (99%) and high efficiency respectively. In Japan, Yamanashi Hitachi Construction Machinery Co., Ltd. has developed a demining machine based on a hydraulic shovel. A rotary cutter attached to the end of the arm destroys mines; the cutter is also used for cutting grasses and bushes. Although many machines with various techniques have been developed, a comprehensive solution that is superior to human manual removal remains elusive. Salient problems are the demining rate, limitation of demining area (MgM Rotar), prohibitive weight and limitation of mine type (RHINO Earth Tiller), and demining efficiency (MgM Rotar, and the demining machine made by Yamanashi Hitachi Construction Machinery Co., Ltd.). Because those machines are operated manually or Humanitarian Demining: Innovative Solutions and the Challenges of Technology 328 by remote control, expert operators are required for each machine. Also, working hours are limited. Recently, various demining robots have been developing mainly at universities. Hirose et al. have developed a probe-type mine detecting sensor that replaces a conventional prod (Kama et al., 2000). It increases safety and reliability. They have also developed a quadruped walking robot TITAN, some snake-type robots, mechanical master-slave hands to remove landmines Mine Hand, and robotic system with pantograph manipulator Gryphon (Hirose et al., 2001a; Hirose et al., 2001b; Furihata et al., 2005; Tojo et al., 2004). Nonami et al. have developed a locomotion robot with six legs for mine detection COMET (Shiraishi et al., 2002). A highly sensitive metal detector installed on the bottom of each foot detects mines and marks the ground. Ushijima et al. proposes a mine detecting system using an airship (Ushijima, 2001). On this system, the airship has a control system and a detecting system for mines using electromagnetic waves; it flies over the minefield autonomously. These studies mainly address mine detection; it is difficult to infer that they effectively consider all processes from detection to disposal. This study proposes an excavation-type demining robot PEACE and presents the possibility of its realization. The robot has a large bucket in front of the body and can travel while maintaining a target depth by tilting the bucket. The robot takes soil into the body and crushes the soil, which includes mines. It then removes broken mine fragments and restores Fi g . 1. M g M Rotar Mk-I Fig. 2. RHINO Earth Tiller PEACE: An Excavation-Type Demining Robot for Anti-Personnal Mines 329 the soil, previously polluted by mines, to a clean condition. In the process, the soil is cultivated, so the land is available for farm use immediately. Expert robot operators are not required; the robot works all day long because it can be controlled autonomously. Section 2 presents the conceptual design of the excavation-type demining robot PEACE. Section 3 describes robot kinematics and trajectory planning. In Section 4, the optimal depth of the excavation is discussed. Section 5 shows experimental results of traveling with digging soil by a scale model of the robot. In Section 6, the structure of the crusher and parameters for crush process are discussed through several experiments. Finally, Section 7 contains summary and future works. 2. Conceptual Design of PEACE The conceptual design of the robot is shown in Fig. 3. The robot uses crawlers for the transfer mechanism because of their high ground-adaptability. The robot has a large bucket on its front. A mine crusher is inside the bucket, and a metal separator is in its body. The first process of demining is to take soil into the body using the bucket. Figure 4 shows the excavating force on the contact point between the bucket and ground. Torque T is generated at the base of the bucket when the bucket rotates. The torque T generates force t F against the ground. The body generates propelling force v F . As the result, contact force F is generated as the resultant force. The rotational direction of the bucket decides the direction of the contact force F . Therefore, the robot can realize both upward motion and downward motion by adjusting the bucket torque T and the propelling force v F . Furthermore, the robot can advance while maintaining a target depth by using some sensors. The next process is to crush mines. The soil is conveyed into the bucket by the conveyor belt 1 in Fig. 3. As the soil is immediately carried, the strong propelling force of the body is not 1. Conveyor belt 1 2. Sensors for ATM 3. Crusher 4. Lattice 5. Conveyor belt 2 6. Metal separator 1 2 6 4 Bucket Body Crawler 3 5 Fig. 3. Conceptual design of the robot Humanitarian Demining: Innovative Solutions and the Challenges of Technology 330 required. The soil, which includes mines, is crushed by the crusher. Most of the blast with the crush escapes from the lattice 4 because the fore of the bucket is underground when demining. The crusher and the bucket are hardly damaged because the explosive power of APMs is so weak to the metal. The sufficient thickness of the steel plate is about 1 cm (Geneva International Centre for Humanitarian Demining, 2002, 2006). The last process is to separate metal splinters of mines from the soil using a metal separator. Crushed debris are conveyed by the conveyer belt 2 in Fig. 3. The metal splinters, which are used for recycling, can be selected by an electromagnet. The rest are discharged from the rear. t F F T v F Bucket Ground Fig. 4. Excavating force on the contact point Fig. 5. Aardvark Mk IV Fig. 6. Armtrac 100 [...]... Protected Demining Operation, Autonomus Robots, 18, pp 337-350 Geneva International Centre for Humanitarian Demining (2002) Mechanical Demining Equipment Catalogue Geneva International Centre for Humanitarian Demining (2006) Mechanical Demining Equipment Catalogue Hirose, S & Kato, K (2001a) Development of the quadruped walking robot, TITAN-IX mechanical design concept and application for the humanitarian. .. Debenest, P.; Fukushima, E F & Hirose, S (2004) Robotic System for Humanitarian Demining Proceedings of International Conference on IEEE Robotics and Automation, pp 2025-2030 346 Humanitarian Demining: Innovative Solutions and the Challenges of Technology Ushijima, K (2001) Mine Detection System Using Blimps Workshop on Humanitarian Demining of Anti-Personnel Mines, pp 55-60, (in Japanese) 15 A Human-Animal-Robot... between length of the bits and ratio of the particle sizes (b) Relationship between gap and ratio of the particle sizes (a) Time response of the electric current (b) Relationship between traveling speed and ratio of the particle sizes of motor Fig 27 Comparison for the traveling speeds 344 Humanitarian Demining: Innovative Solutions and the Challenges of Technology Figure 25 shows the experimental results... angle of the body The bucket followed the trajectory and dug to near the goal depth 6 Crush Process The processing reliability of demining machines or robots is the most important to humanitarian demining The main point is the crush process Most conventional rotor-type demining machines have rotor bits that are larger than mines Therefore, it is possible that the mines do not touch the bits and they... Nakamura, T (2003) Conceptual Design of an Excavation-type Demining Robot Proceedings of the 11th Int Conf on Advanced Robotics, Vol.1, pp 532-537 Mori, Y.; Takayama, K.; Adachi, T.; Omote, S & Nakamura, T (2005) Feasibility Study on an Excavation-Type Demining Robot Autonomous Robots 18, pp 263-274 Shibata, T (2001) Research and Development of Humanitarian Demining in Robotics, Journal of the Robotics Society... supplied to the rotor motor was constant In the conventional demining machines, the frequency is at most as 700 rpm (Geneva International Centre for Humanitarian Demining, 2002, 2006) Figure 24 (a) shows that high rotational frequency leads to continuous crush Figure 24 (b) shows that high rotational frequency is related to fineness of the particle sizes of the samples after the crush, that is, high... and ratio of the particle sizes Fig 24 Comparison for the rotational frequencies PEACE: An Excavation-Type Demining Robot for Anti-Personnal Mines (a) Time response of the electric current of motor Fig 25 Comparison for the lengths of bits (a) Time response of the electric current of motor Fig 26 Comparison for the gaps 343 (b) Relationship between length of the bits and ratio of the particle sizes (b)... time 4 PEACE is designed to work after clearing ATMs and UXOs In order to clear them, chain flail type demining machine, e.g Aardvark Mk IV or Armtrac 100 would be suitable in terms of the mobility, the simplicity and the maintenance (see Figs 5 and 6, Geneva International Centre for Humanitarian Demining, 2002, 2006) If the robot should detect ATMs by using sensors for ATM 2, it would stop before... it was confirmed that small distance is desirable for humanitarian demining operation Figure 27 shows the experimental results to the three kinds of traveling speeds of the robot: 10 mm/s, 15 mm/s and 20 mm/s As the robot traveled faster, the maximum value of the electric current of the motor increased However, there is little difference to the particle sizes of the samples after the crush Therefore,... reliability cannot be realized without the sifting process Almost all of conventional machines, however, have no such process Although MgM Rotar has this process, the demining efficiency is not so high (Geneva International Centre for Humanitarian Demining, 2002) We discuss the structure of the crusher We made the test equipment shown in Figs 22 and 23 in order to examine the validity of it and the improved . Symposium Humanitarian Demining 2007 – Mechanical Demining 24 - 27 April, Šibenik, Croatia. (to be published in 2007) Habib, M.K. (2002). Mechanical mine clearance technologies and humanitarian demining. . Mechanical demining equipment catalogue. Geneva Int. Center for Humanitarian Demining. (www.gichd.ch), March 2006, ISBN 2-88487-026-1 GICHD (2004). A study of mechanical application in demining. . problems are the demining rate, limitation of demining area (MgM Rotar), prohibitive weight and limitation of mine type (RHINO Earth Tiller), and demining efficiency (MgM Rotar, and the demining machine