References of "Ahmad, Rafiq 50000011"
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See detailRobot and Human safety in a semi-automated assembly workspace
Ahmad, Rafiq UL

in IEEE transactions (2015, October 02)

Robots used for automation in industries should be able to react to any uncomfortable situations in their vicinity in order to avoid harming humans, working product, other machinery and itself. The ... [more ▼]

Robots used for automation in industries should be able to react to any uncomfortable situations in their vicinity in order to avoid harming humans, working product, other machinery and itself. The manipulator robots might not only be able to predict potential collisions but should also be able to take intelligent decisions for automatically avoiding them with a safe detour around the obstacles. This paper introduces a 3D-Time- of-Flight sensor based SARPP algorithm which automatically plans path for the robot in a human robot collaborative semi- automated assembly environment. The application of algorithm can be foreseen in more complex Human-Robot-Collaborative industrial environment where the safety of human as well as robots are the highest priority. [less ▲]

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See detailGeneration of safe tool-path for 2.5D milling/drilling machine-tool using 3D ToF sensor
Ahmad, Rafiq UL; Plapper, Peter UL

in CIRP - Journal of Manufacturing Science and Technology (2015), 10

The complexity of multi-axis, milling and drilling CNC machines and the demand of high precision for complex parts production increase the importance of safe and efficient tool-paths generation during ... [more ▼]

The complexity of multi-axis, milling and drilling CNC machines and the demand of high precision for complex parts production increase the importance of safe and efficient tool-paths generation during manufacturing. In these machines, multi-tool working in the same area, or static un-programed machine elements, such as fixtures, another work-part may cause collision problems. It is important to know the collision risks in advance during production in order to avoid unexpected production stops, and machinery damage. This research study is focusing on automatic collision detection and avoidance for safe non-functional (rapid) tool-path generation in a static 2.5D milling or drilling machining environment, as an initial step toward complex, dynamic multi-axis machine-tool manufacturing. A 3D vision based Time of Flight (ToF) sensor provides the depth information about the manufacturing scene that are exploited by the method presented for taking an effective decision to automatically detect and avoid collisions in order to achieve safe tool-path during production. The concept presented opens up new areas for research and application of ToF camera in a CNC manufacturing environment for tool-path planning. The results obtained are for traversal safe tool-paths in a static environment, which will be adapted to more complex and dynamic real machining scenarios by integrating it with STEP-NC technology in future. [less ▲]

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See detailSafe and Automated Assembly Process using Vision assisted Robot Manipulator
Ahmad, Rafiq UL; Plapper, Peter UL

in Procedia CIRP (2015)

Many manufacturing industries especially small and medium size (SMEs) industries are reluctant to automatize their production using robots. This is due to the fact that mostly industrial robots are not ... [more ▼]

Many manufacturing industries especially small and medium size (SMEs) industries are reluctant to automatize their production using robots. This is due to the fact that mostly industrial robots are not properly equipped to recognize their surrounding and take intelligent decisions regarding path planning especially for low volume, flexible production with versatile production lines. The proposed idea is that a robot manipulator performing assembly or disassembly tasks should be able to predict potential collisions even with unknown obstacles and must be able to prevent i.e. react automatically for safe detour around obstacle. Currently, industrial robots have tactile sensing abilities, which detect collisions after a real contact but the existing proposals for its avoidance are either computationally expensive, need prior information about the obstacles or not very well adapted to the safety standards. Therefore, this paper introduces a ToF sensor based information collection and intelligent decision methodology in order to localize the un-known, un-programmed obstacles and propose a safe peg-in-hole automated assembly process. In the case of collisions, the proposed method will provide various solutions and decides for the best solution according to the scenario on-hand. The proposed solution is quick and robust and currently applied for static environment, whereas dynamic obstacles will be treated in future. [less ▲]

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See detailAnt-Air self-learning algorithm for path planning in a cluttered environment
Ahmad, Rafiq UL; Plapper, Peter UL

in Applied Mechanics and Materials Journal (2014, December)

Path planning in unstructured area while dealing with narrow spaces is an area of research which is receiving extensive interest. Many existing algorithms are able to produce safe paths but the presented ... [more ▼]

Path planning in unstructured area while dealing with narrow spaces is an area of research which is receiving extensive interest. Many existing algorithms are able to produce safe paths but the presented concepts are either not adapted to narrow spaces or they are unable to learn from the past experience to improve repeated movements from the same agent or followed trajectories by other agents. This paper introduces an original concept based on Ant-Air phenomenon for safe path planning in a cluttered environment where narrow passages are treated. The algorithm presented is able to learn from the past experience and hence improve the already generated trajectory further by using some lessons learned from the past experience. The concept is applicable in various domains such as mobile robot path planning, manipulator trajectory generation and part movement in narrow passages in real or virtual assembly/disassembly process. [less ▲]

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See detailHuman-Robot Collaboration: Twofold strategy algorithm to avoid collisions using ToF sensor
Ahmad, Rafiq UL; Plapper, Peter UL

in Applied Mechanics and Materials Journal (2014, December)

The importance of Human Robot Interaction to complement human skills in a manufacturing environment with industrial robots increases the concerns over safety of human and the robot. It is necessary to ... [more ▼]

The importance of Human Robot Interaction to complement human skills in a manufacturing environment with industrial robots increases the concerns over safety of human and the robot. It is necessary to identify collision risks and avoid them otherwise production stops may cost a huge amount to the industry. A robot working at manufacturing facility should be able to predict potential collisions and must be able to prevent i.e. react automatically for safe detour around obstacle/human. Currently, industrial robots are able to detect collisions after a real contact but the existing proposals for avoiding collisions are either computationally expensive or not very well adapted to human safety. The objective of this paper is to provide intelligence to the industrial robot to predict collision risks and react automatically without stopping the production in a static environment. The proposed approach using Time of Flight (TOF) camera, provides decision regarding trajectory correction and improvement by shifting robot to a secure position. The application presented in this paper is for safe KUKA robot trajectory generation in peg-in-hole assembly process in the laboratory context. [less ▲]

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See detailSafe and Automated Tool-Path Generation for Multi-Axis Production Machines
Ahmad, Rafiq UL; Plapper, Peter UL

in Transactions of the American Society of Mechanical Engineers (2014, November 14), 2B(Advanced Manufacturing), 0202034-7

Multi-axis machines are growing rapidly their precision and complexity with the increasing importance of machine intelligence, automation, optimization and safety. It is necessary to identify collision ... [more ▼]

Multi-axis machines are growing rapidly their precision and complexity with the increasing importance of machine intelligence, automation, optimization and safety. It is necessary to identify collision risks and avoid them in manufacturing otherwise production stops may cost a huge amount to the manufacturing company. This study has focused on safe trajectory generation for CNC machines especially focusing on high risked non-functional trajectories. These machines should be able to see any unwilling situation (i.e. collisions) in their vicinity and must be able to detect and react automatically in real-time for safe tool movements. Currently CAM software and some multi-axis machines are able to detect collisions but they do not have any solution to avoid such collisions automatically. The main objective is to make multi-axis machine vision system effective enough that it can see all its activities regarding collisions and can react or command automatically online as well as off-line for real and virtual productions. In presence of obstacles during manufacturing, the proposed approach will provide decisions regarding trajectory correction and improvement automatically. The proposed vision concept is able to take into account the evolution of the scene i.e. the aspects of changes to the obstacle like shape, size or presence during production. The application presented in this paper is for 2D traversal safe online trajectories generation in virtual simulated dynamic environment, which will be adapted to the real-time real machining scenarios at shop-floor by integrating it with STEP-NC technology in future. [less ▲]

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See detail2D Tool-Path Generation Method for Multi-Axis Milling Machine using ToF camera
Ahmad, Rafiq UL; Plapper, Peter UL

Scientific Conference (2014, September 12)

Multi-axis machines are known for their precise production of complex parts, where multi-tool are working in the same area or static workpiece support or clamping parts, may cause collision problems. It ... [more ▼]

Multi-axis machines are known for their precise production of complex parts, where multi-tool are working in the same area or static workpiece support or clamping parts, may cause collision problems. It is therefore necessary to identify potential collision risks and avoid them in an efficient way, which may cause production stops and machinery damage. This research study has been focusing on safe non-functional (rapid) tool-path generation for multi-axis milling machine, where no efficient automatic collision avoidance solution exists (in the literature). A 3D Time of Flight (TOF) camera attached into the machine will be able to sense any unwanted situation in the manufacturing environment and provide rapid and automatic solution to detect and avoid collisions for safe tool movements during production. In the presence of obstacles, the proposed approach will provide decisions regarding tool-path correction and improvement automatically. The proposed algorithm based on 3D vision concept is also able to take into account unknown obstacle shape, size during production but dynamic aspects of the scene will be treated in future. The concept presented take into account the 3D information from the scene for traversal safe tool-paths generation for a static environment as an initial application, which will be adapted to more complex real machining scenarios by integrating it with STEP-NC technology in future. [less ▲]

Detailed reference viewed: 98 (6 UL)