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An exploration of nonprehensile twopalm manipulation: Planning and execution
 In Robotics Research: The Seventh International Symposium, G. Giralt and
, 1996
"... This paper describes our current research into nonprehensile palm manipulation. The term “palm ” refers to the use of the entire device surface during manipulation, as opposed to use of the fingertips alone. ..."
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Cited by 82 (14 self)
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This paper describes our current research into nonprehensile palm manipulation. The term “palm ” refers to the use of the entire device surface during manipulation, as opposed to use of the fingertips alone.
A Complete Algorithm for Designing Passive Fences to Orient Parts
, 1996
"... this paper we describe the first complete algorithm to design such sequences for a given convex polygonal part. The algorithm is complete in the sense that it is guaranteed to find a design if one exists and to terminate with a negative report otherwise. Based on an exact breadthfirst search of the ..."
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Cited by 75 (14 self)
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this paper we describe the first complete algorithm to design such sequences for a given convex polygonal part. The algorithm is complete in the sense that it is guaranteed to find a design if one exists and to terminate with a negative report otherwise. Based on an exact breadthfirst search of the design space, the algorithm is also guaranteed to find the design requiring the fewest fences. We describe the algorithm and compare results with those previously reported. We conjecture that a fence design exists to orient any convex polygonal part.
Posing Polygonal Objects in the Plane by Pushing
 In IEEE International Conference on Robotics and Automation
, 1992
"... This paper studies the use of pushing actions with a fence to orient and translate objects in the plane. It describes a planner which is guaranteed to construct a sequence of pushing actions to move any polygonal object from any initial configuration to any final configuration. This planner, which u ..."
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Cited by 62 (4 self)
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This paper studies the use of pushing actions with a fence to orient and translate objects in the plane. It describes a planner which is guaranteed to construct a sequence of pushing actions to move any polygonal object from any initial configuration to any final configuration. This planner, which utilizes an analysis of the mechanics of pushing an object, generates openloop plans which do not require feedback sensing. These plans are guaranteed to succeed provided certain physical assumptions are met. We present results of experiments conducted to demonstrate the generated plans. 1 Introduction The manipulation of objects restricted to motions in the plane is important in cases where the object cannot be grasped or it is more efficient to move the object in the plane. An example is planar parts transfer, where parts are to be moved from one position to another in the plane, often with a change in orientation. In this paper, we develop a method to find openloop plans, which do not r...
Parts Feeding on a Conveyor with a One Joint Robot
, 2000
"... . This paper explores a method of manipulating a planar rigid part on a conveyor belt using a robot with just one joint. This approach has the potential of offering a simple and flexible method for feeding parts in industrial automation applications. In this paper we develop a model of this system a ..."
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Cited by 42 (7 self)
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. This paper explores a method of manipulating a planar rigid part on a conveyor belt using a robot with just one joint. This approach has the potential of offering a simple and flexible method for feeding parts in industrial automation applications. In this paper we develop a model of this system and of a variation which requires no sensing. We have been able to characterize these systems and to prove that they can serve as parts feeding devices for planar polygonal parts. We present the planners for these systems and describe our implementations. Key Words. Robotics, Manipulation, Mechanics, Planning, Minimalism, Automation, Manufacturing, Parts feeding. 1. Introduction. The most straightforward approach to planar manipulation is to use a rigid grasp and a robot with at least three joints, corresponding to the three motion freedoms of a planar rigid part, but three joints are not really necessary to manipulate a part in the plane. In this paper we achieve effective control of all t...
Complementarity Formulations and Existence of Solutions of Dynamic MultiRigidBody Contact Problems with Coulomb Friction
 Mathematical Programming
"... . In this paper, we study the problem of predicting the acceleration of a set of rigid, 3dimensional bodies in contact with Coulomb friction. The nonlinearity of Coulomb's law leads to a nonlinear complementarity formulation of the system model. This model is used in conjunction with the theory of ..."
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Cited by 42 (6 self)
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. In this paper, we study the problem of predicting the acceleration of a set of rigid, 3dimensional bodies in contact with Coulomb friction. The nonlinearity of Coulomb's law leads to a nonlinear complementarity formulation of the system model. This model is used in conjunction with the theory of quasivariational inequalities to prove for the first time that multirigidbody systems with all contacts rolling always has a solution under a feasibilitytype condition. The analysis of the more general problem with sliding and rolling contacts presents difficulties that motivate our consideration of a relaxed friction law. The corresponding complementarity formulations of the multirigidbody contact problem are derived and existence of solutions of these models is established. Key Words. Rigidbody contact problem, Coulomb friction, linear complementarity, quasivariational inequality, setvalued mappings. 1 Introduction One of the main goals of the robotics research community is to a...
Manipulating Algebraic Parts in the Plane
, 1993
"... When manipulating parts, it is important to determine the orientation of the part with respect to the gripper. This orientation may not be known precisely or may be disturbed by the act of grasping. It is in some cases possible to use mechanical compliance to orient parts during grasping. It was rec ..."
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Cited by 31 (9 self)
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When manipulating parts, it is important to determine the orientation of the part with respect to the gripper. This orientation may not be known precisely or may be disturbed by the act of grasping. It is in some cases possible to use mechanical compliance to orient parts during grasping. It was recently shown [14] that any part with polygonal boundary can be oriented and grasped in this manner using a paralleljaw gripper. Many of the curves currently used in engineering design are algebraic but nonlinear. Although these curves can be approximated as polygons for the purpose of visualization, such approximations can lead to false conclusions about mechanical behavior. In this paper we consider the class of parts whose planar projection has a piecewise algebraic convex hull. Our primary result is a proof that a grasp plan exists for any such part. We give a planning algorithm that produces the shortest plan and runs in time O(n² log n + N ), where n is the number of transitions in ...
Prediction of the Quasistatic Planar Motion of a Contacted Rigid Body
 IEEE Transactions on Robotics and Automation
, 1995
"... Planning the motion of bodies in contact requires a model of contact mechanics in order to predict sliding, rolling, and jamming. Such a model typically assumes that the bodies are rigid and that tangential forces at the contacts obey Coulomb's law. Though, usually assumed to be constant, the static ..."
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Cited by 24 (9 self)
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Planning the motion of bodies in contact requires a model of contact mechanics in order to predict sliding, rolling, and jamming. Such a model typically assumes that the bodies are rigid and that tangential forces at the contacts obey Coulomb's law. Though, usually assumed to be constant, the static and dynamic coefficients of friction vary in space and time and are difficult to measure accurately. In this paper, we study a quasistatic, multirigidbody model for planar systems, in which the coefficients of friction are treated as independent variables. Our analysis yields inequalities defining regions in the space of friction coefficients for which a particular contact mode (i.e., a particular combination of sliding, rolling, or separating at the contacts) is feasible. The geometrical interpretation of these inequalities leads to a simple graphical technique to test contact mode feasibility. This technique is then used to generate a nontrivial example in which several contact modes ar...
Nonprehensile Two Palm Manipulation with NonEquilibrium Transitions between Stable States
 In Proc. IEEE Int. Conf. on Robotics and Automation (ICRA
, 1996
"... Manipulation without prehension is a natural way of handling objects for both humansand machines. Nonprehensile operations are appropriate when complete constraint over the object to be manipulated is either undesirableor impractical, but some control overthe object is desired over its entire trajec ..."
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Cited by 24 (3 self)
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Manipulation without prehension is a natural way of handling objects for both humansand machines. Nonprehensile operations are appropriate when complete constraint over the object to be manipulated is either undesirableor impractical, but some control overthe object is desired over its entire trajectory, in orderto bring the object reliably to a desired final state. Research to date has explored only a small portion of this class. We are interested in controlling the shape of the constraint surfaces so that constraint and externalforcesnaturally attract the systemto the desired state, even if the object momentarily loses stability during the motion. We present a preliminary analysisof the nonprehensile orientation of planar objects by two low friction palms joined at a central hinge. These palms support an object in a gravitational field, without grasping or gripping. We determine connected regions of stable states of the object, and give a method of planning part orientation based on ...
Nonprehensile Robotic Manipulation: Controllability and Planning
, 1997
"... the author and should not be interpreted as representing the o cial policies, either expressed or A good model of the mechanics of a task is a resource for a robot, just as actuators and sensors are resources. The e ective use of frictional, gravitational, and dynamic forces can substitute for extra ..."
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Cited by 23 (5 self)
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the author and should not be interpreted as representing the o cial policies, either expressed or A good model of the mechanics of a task is a resource for a robot, just as actuators and sensors are resources. The e ective use of frictional, gravitational, and dynamic forces can substitute for extra actuators; the expectation derived from a good model can minimize sensing requirements. Despite this, most robot systems attempt to dominate or nullify task mechanics, rather than exploit them. There has been little e ort to understand the manipulation capabilities of even the simplest robots under more complete mechanics models. This thesis addresses that knowledge de cit by studying graspless or nonprehensile manipulation. Nonprehensile manipulation exploits task mechanics to achieve a goal state without grasping, allowing simple mechanisms to accomplish complex tasks. With nonprehensile manipulation, a robot can manipulate objects too large or heavy to be grasped and lifted, and a lowdegreeoffreedom robot can control more degreesoffreedom of an object by allowing relative motion between the object and the manipulator. Two key problems are determining controllability of and motion planning for
Complete Algorithms for Feeding Polyhedral Parts using Pivot Grasps
, 1995
"... To rapidly feed industrial parts on an assembly line, Carlisle et. al. [7] proposed a flexible part feeding system that drops parts on a flat conveyor belt, determines position and orientation of each part with a vision system, and then moves them into a desired orientation. A robot arm with 4 degre ..."
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Cited by 18 (7 self)
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To rapidly feed industrial parts on an assembly line, Carlisle et. al. [7] proposed a flexible part feeding system that drops parts on a flat conveyor belt, determines position and orientation of each part with a vision system, and then moves them into a desired orientation. A robot arm with 4 degrees of freedom (DoF) is capable of moving parts through 6 DoF when equipped with a passive pivoting axis between the parallel jaws of its gripper. The idea is to grasp a part with 2 hard finger contacts such that it pivots, under gravity, into a desired orientation when lifted and replaced on the table. We refer to these actions as pivot grasps. This paper considers the planning problem. Given a polyhedral part shape, coefficient of friction and a pair of stable configurations as input, find pairs of grasp points that will cause the part to pivot from one stable configuration to the other. For some transitions, pivot grasps may not exist. For a part with n faces and m stable configurations, ...