Automatic decomposition of planned assembly sequences into skill primitives

This paper presents a new method to decompose complex sequences of assembly operations into skill primitives. This can be realized by analyzing hyper-arcs of the underlying AND/OR graphs representing automatically generated assembly plans. Features like local depart spaces, symbolic spatial relations, and the necessary tools classify the type of assembly operation (peg in hole, placements, alignments, etc.). Skill primitives are robot movements or commands for grippers and tools. The unified modeling language is used to model the robot tasks and skill primitives. A robot control system uses the skill primitives as input to select the desired control scheme (position, force, or hybrid). In addition to this, we use an algorithm to identify assembly process states considering static friction under uniform gravity to execute skill primitives. This enables a robot to select and modify its motion strategies adequately according to the state of the assembly operation.

[1]  John Kenneth Salisbury,et al.  Contact Sensing from Force Measurements , 1990, Int. J. Robotics Res..

[2]  K. Suzanne Barber,et al.  Design of an experience-based assembly sequence planner for mechanical assemblies , 1998, Robotica.

[3]  A. Bourjault.  Methodology of Assembly Automation: A New Approach , 1988 .

[4]  Arthur C. Sanderson,et al.  Task sequence planning for robotic assembly , 1989 .

[5]  Matthew T. Mason,et al.  Compliance and Force Control for Computer Controlled Manipulators , 1981, IEEE Transactions on Systems, Man, and Cybernetics.

[6]  Friedrich M. Wahl,et al.  Generating and evaluating stable assembly sequences , 1996, Adv. Robotics.

[7]  Randall H. Wilson,et al.  The Archimedes 2 mechanical assembly planning system , 1996, Proceedings of IEEE International Conference on Robotics and Automation.

[8]  H.S. Cho,et al.  Disassemblability analysis for generating robotic assembly sequences , 1995, Proceedings of 1995 IEEE International Conference on Robotics and Automation.

[9]  D. Dutta,et al.  Automatic Disassembly and Total Ordering in Three Dimensions , 1991 .

[10]  Jan D. Wolter.  On the automatic generation of assembly plans , 1989, Proceedings, 1989 International Conference on Robotics and Automation.

[11]  Pradeep K. Khosla,et al.  Finding all stable orientations of assemblies with friction , 1996, IEEE Trans. Robotics Autom..

[12]  Gregory D. Hager,et al.  Task-Directed Sensor Fusion and Planning , 1990 .

[13]  Lydia E. Kavraki,et al.  Partitioning a Planar Assembly Into Two Connected Parts is NP-Complete , 1995, Inf. Process. Lett..

[14]  Michael H. Goldwasser,et al.  AN EFFICIENT SYSTEM FOR GEOMETRIC ASSEMBLY SEQUENCE GENERATION AND EVALUATION , 1995 .

[15]  John J. Craig,et al.  Hybrid position/force control of manipulators , 1981 .

[16]  Friedrich M. Wahl,et al.  Assembly stability as a constraint for assembly sequence planning , 1998, Proceedings. 1998 IEEE International Conference on Robotics and Automation (Cat. No.98CH36146).

[17]  Joris De Schutter,et al.  Contact identification and monitoring based on energy , 1996, Proceedings of IEEE International Conference on Robotics and Automation.

[18]  Tien-Chien Chang,et al.  3D MAPS: Three-dimensional mechanical assembly planning system , 1993 .

[19]  Thomas L. DeFazio,et al.  Simplified generation of all mechanical assembly sequences , 1987, IEEE Journal on Robotics and Automation.

[20]  Jianwei Zhang,et al.  Instructing cooperating assembly robots through situated dialogues in natural language , 1997, Proceedings of International Conference on Robotics and Automation.

[21]  Oussama Khatib,et al.  A unified approach for motion and force control of robot manipulators: The operational space formulation , 1987, IEEE J. Robotics Autom..

[22]  Christian Laugier,et al.  Planning fine motion strategies by reasoning in the contact space , 1989, Proceedings, 1989 International Conference on Robotics and Automation.

[23]  Takashi Suehiro,et al.  Skill-based backprojection for fine motion planning , 1996, Proceedings of IEEE/RSJ International Conference on Intelligent Robots and Systems. IROS '96.

[24]  Sukhan Lee,et al.  Assemblability evaluation based on tolerance propagation , 1995, Proceedings of 1995 IEEE International Conference on Robotics and Automation.

[25]  Shinichi Hirai,et al.  Kinematics and Statics of Manipulation Using the Theory of Polyhedral Convex Cones , 1993, Int. J. Robotics Res..

[26]  R.H. Wilson,et al.  On constraints in assembly planning , 1998, IEEE Trans. Robotics Autom..

[27]  Rajiv S. Desai,et al.  Identification and verification of termination conditions in fine motion in presence of sensor errors and geometric uncertainties , 1989, Proceedings, 1989 International Conference on Robotics and Automation.

[28]  Friedrich M. Wahl,et al.  Generating polyhedral convex cones from contact graphs for the identification of assembly process states , 2000, Proceedings 2000 ICRA. Millennium Conference. IEEE International Conference on Robotics and Automation. Symposia Proceedings (Cat. No.00CH37065).

[29]  T. Suehiro,et al.  A model-based manipulation system with skill-based execution in unstructured environment , 1991 .

[30]  Rajeev Sharma,et al.  Interactive evaluation of assembly sequences using augmented reality , 1999, IEEE Trans. Robotics Autom..

[31]  Jing Xiao,et al.  A general strategy to determine geometrically valid contact formations from possible contact primitives , 1995, Proceedings of 1995 IEEE International Conference on Robotics and Automation.

[32]  Sukhan Lee,et al.  Computer-Aided Mechanical Assembly Planning , 1991 .

[33]  Friedrich M. Wahl,et al.  Stability analysis of assemblies considering friction , 1997, IEEE Trans. Robotics Autom..

[34]  Shinichi Hirai.  Identification of contact states based on a geometric model for manipulative operations , 1993, Adv. Robotics.

[35]  Daniel E. Whitney,et al.  Modeling and controlling variation propagation in mechanical assemblies using state transition models , 1999, IEEE Trans. Robotics Autom..

[36]  Jing Xiao,et al.  Automatic Generation of High-Level Contact State Space , 1999, Proceedings 1999 IEEE International Conference on Robotics and Automation (Cat. No.99CH36288C).

[37]  D. Taghirad.  Ieee Transactions on Robotics and Automation 1 Robust Torque Control of Harmonic Drive Systems , 1997 .

[38]  Tomás Lozano-Pérez,et al.  LAMA: A Language for Automatic Mechanical Assembly , 1977, IJCAI.

[39]  Friedrich M. Wahl,et al.  Identification of assembly process states using polyhedral convex cones , 1999, Proceedings 1999 IEEE International Conference on Robotics and Automation (Cat. No.99CH36288C).

[40]  Friedrich M. Wahl,et al.  Stability of Assemblies as a Criterion for Cost Evaluation in Robot Assembly , 1998 .

[41]  Ann Patricia Fothergill,et al.  An Interpreter for a Language for Describing Assemblies , 1980, Artif. Intell..

[42]  K. Rathmill,et al.  The Development of a European Benchmark for the Comparison of Assembly Robot Programming Systems , 1985 .