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Full-Text Articles in Mechanical Engineering
One-Class-At-A-Time Removal Sequence Planning Method For Multiclass Classification Problems, Chieh-Neng Young, Chen-Wen Yen, Yi-Hua Pao, Mark L. Nagurka
One-Class-At-A-Time Removal Sequence Planning Method For Multiclass Classification Problems, Chieh-Neng Young, Chen-Wen Yen, Yi-Hua Pao, Mark L. Nagurka
Mechanical Engineering Faculty Research and Publications
Using dynamic programming, this work develops a one-class-at-a-time removal sequence planning method to decompose a multiclass classification problem into a series of two-class problems. Compared with previous decomposition methods, the approach has the following distinct features. First, under the one-class-at-a-time framework, the approach guarantees the optimality of the decomposition. Second, for a K-class problem, the number of binary classifiers required by the method is only K-1. Third, to achieve higher classification accuracy, the approach can easily be adapted to form a committee machine. A drawback of the approach is that its computational burden increases rapidly with the number of classes. …
Spatial Admittance Selection Conditions For Frictionless Force-Guided Assembly Of Polyhedral Parts In Single Principal Contact, Shuguang Huang, Joseph M. Schimmels
Spatial Admittance Selection Conditions For Frictionless Force-Guided Assembly Of Polyhedral Parts In Single Principal Contact, Shuguang Huang, Joseph M. Schimmels
Mechanical Engineering Faculty Research and Publications
By judiciously selecting the admittance of a manipulator, the forces of contact that occur during assembly can be used to guide the parts to proper positioning. This paper identifies conditions for selecting the appropriate spatial admittance to achieve reliable force-guided assembly of polyhedral parts for cases in which a single feature (vertex, edge, or face) of one part contacts a single feature of the other, i.e., all single principal contact cases. These conditions ensure that the motion that results from frictionless contact always instantaneously reduces part misalignment. We show that, for bounded misalignments, if an admittance satisfies the misalignment-reducing conditions …
Robust Procedures For Obtaining Assembly Contact State Extremal Configurations, Pan Feng, Joseph M. Schimmels
Robust Procedures For Obtaining Assembly Contact State Extremal Configurations, Pan Feng, Joseph M. Schimmels
Mechanical Engineering Faculty Research and Publications
Two important components in the selection of an admittance that facilitates force-guided assembly are the identification of: 1) the set of feasible contact states, and 2) the set of configurations that span each contact state, i.e., the extremal configurations. We present a procedure to automatically generate both sets from CAD models of the assembly parts. In the procedure, all possible combinations of principle contacts are considered when generating hypothesized contact states. The feasibility of each is then evaluated in a genetic algorithm based optimization procedure. The maximum and minimum value of each of the 6 configuration variables spanning each contact …
Sufficient Conditions For Admittance To Ensure Planar Force-Assembly In Multi-Point Frictionless Contact, Shuguang Huang, Joseph M. Schimmels
Sufficient Conditions For Admittance To Ensure Planar Force-Assembly In Multi-Point Frictionless Contact, Shuguang Huang, Joseph M. Schimmels
Mechanical Engineering Faculty Research and Publications
An important issue in the development of force guidance assembly strategies is the specification of an appropriate admittance control law. This paper identifies procedures for selecting the appropriate admittance to achieve reliable planar force-guided assembly for multi-point contact cases. Conditions that restrict the admittance behavior for each of the various types of two-point contact are presented. These conditions ensure that the motion that results from contact reduces part misalignment for each case. We show that, for bounded misalignments, if the conditions are satisfied for a finite number of contact configurations, the conditions ensure that force guidance is achieved for all …
Efficient Contact State Graph Generation For Assembly Applications, Feng Pan, Joseph M. Schimmels
Efficient Contact State Graph Generation For Assembly Applications, Feng Pan, Joseph M. Schimmels
Mechanical Engineering Faculty Research and Publications
An important aspect in the design of many automated assembly strategies is the ability to automatically generate the set of contact states that may occur during an assembly task. In this paper, we present an efficient means of constructing the set of all geometrically feasible contact states that may occur within a bounded set of misalignments (bounds determined by robot inaccuracy). This set is stored as a graph, referred to as an Assembly Contact State Graph (ACSG), which indicates neighbor relationships between feasible states. An ACSG is constructed without user intervention in two stages. In the first stage, all hypothetical …
Admittance Selection For Planar Force-Guided Assembly For Single-Point Contact With Friction, Shuguang Huang, Joseph M. Schimmels
Admittance Selection For Planar Force-Guided Assembly For Single-Point Contact With Friction, Shuguang Huang, Joseph M. Schimmels
Mechanical Engineering Faculty Research and Publications
This paper identifies procedures for selecting the appropriate admittance to achieve reliable planar force-guided assembly for single-point frictional contact cases. A set of conditions that are imposed on the admittance matrix is presented. These conditions ensure that the motion that results from contact reduces part misalignment. We show that, for bounded misalignments, if an admittance satisfies the misalignment-reduction conditions at a finite number of contact configurations and a given coefficient of friction /spl mu//sub M/) then the admittance will also ensure that the conditions are satisfied at all intermediate configurations for all coefficients less than /spl mu//sub M/.