The Experts below are selected from a list of 345732 Experts worldwide ranked by ideXlab platform
Guy Bessonnet - One of the best experts on this subject based on the ideXlab platform.
-
Sagittal gait of a biped robot during the single Support Phase. Part 2: optimal motion
Robotica, 2001Co-Authors: Mostafa Rostami, Guy BessonnetAbstract:The paper is aimed at generating optimal swing motions during the single-Support Phase of sagittal gait. Unlike the previous Part 1 which deals with passive motions, all joints of the biped are assumed to be active in the present Part 2. The final conditions specify an impactless heel-touch in order to avoid a destabilizing effect on the biped motion. As the biped is essentially submitted to gravity forces, the motion is generated by minimizing the joint actuating torques. Feasible motions are defined by state inequality constraints limiting joint motions, and defining foot clearance and obstacle avoidance during the swing. The optimization problem is dealt with using Pontryagin's Maximum Principle. A final two-point boundary value problem is solved by implementing a shooting method. The approach presented is illustrated by various numerical simulations applying to a seven-body planar biped which has four or five active joints during the swing Phase.
-
Sagittal gait of a biped robot during the single Support Phase. Part 1: passive motion
Robotica, 2001Co-Authors: Mostafa Rostami, Guy BessonnetAbstract:The paper is aimed at generating optimal swing motions during the single-Support Phase of sagittal gait. Unlike the previous Part 1 which deals with passive motions, all joints of the biped are assumed to be active in the present Part 2. The final conditions specify an impactless heel-touch in order to avoid a destabilizing effect on the biped motion. As the biped is essentially submitted to gravity forces, the motion is generated by minimizing the joint actuating torques. Feasible motions are defined by state inequality constraints limiting joint motions, and defining foot clearance and obstacle avoidance during the swing. The optimization problem is dealt with using Pontryagin's Maximum Principle. A final two-point boundary value problem is solved by implementing a shooting method. The approach presented is illustrated by various numerical simulations applying to a seven-body planar biped which has four or five active joints during the swing Phase.
-
ICRA - Impactless sagittal gait of a biped robot during the single Support Phase
Proceedings. 1998 IEEE International Conference on Robotics and Automation (Cat. No.98CH36146), 1Co-Authors: Mostafa Rostami, Guy BessonnetAbstract:The problem of generating optimal sagittal reference gaits in bipedal walking is addressed. In our study the single-Support Phase during which the biped reaches its highest instability is considered. The approach developed allows for a fully dynamic model of the biped, and is based on minimizing the integral of quadratic joint actuating torques. Impactless and non-sliding heel-touch is accounted for, ensuring a more stable and easier controlled walking. Optimal motion synthesis is achieved by applying the Pontryagin maximum principle. Two numerical simulations are presented. Computed optimal motions reveal anthropomorphic gait characteristics.
Mostafa Rostami - One of the best experts on this subject based on the ideXlab platform.
-
Gait Optimization of Biped Robot during Double Support Phase by Pure Dynamic Synthesis
American Journal of Applied Sciences, 2008Co-Authors: Nima Jamshidi, Mostafa RostamiAbstract:This paper deals with dynamic optimization of biped locomotion. The main focus of this research is motion optimization of double Support Phase. The optimization problem is dealt by using Pontryagins Maximum Principal. For motion optimization of double Support Phase, the closed kinematic chain has been considered to be opened at appropriate joint and the components of ground reaction forces has been applied on the tip of front leg and finally the penalty method has been used to tighten the leg to its prescribed location. The feasible sets of motion are taken into consideration by using inequality constraint to limit the joint motion. Also the components of ground reaction forces on front leg have been introduced as control variables in optimization of double Support Phase. The proposed technique has the ability to generate optimal free motions without specifying joint trajectories and minimized the performance criterion based on joint actuating torques. The two point boundary value problem has been solved by implementing a shooting method. This technique allows for specifying a few parameters to characterize gait pattern. The optimization process has the ability to generate a motion with a minimum of postural and kinematics data. Unlike previous research which used computational intelligent techniques for biped gait optimization, this study focuses on development of purely dynamic synthesis of biped motion during the double Support Phase.
-
Sagittal gait of a biped robot during the single Support Phase. Part 2: optimal motion
Robotica, 2001Co-Authors: Mostafa Rostami, Guy BessonnetAbstract:The paper is aimed at generating optimal swing motions during the single-Support Phase of sagittal gait. Unlike the previous Part 1 which deals with passive motions, all joints of the biped are assumed to be active in the present Part 2. The final conditions specify an impactless heel-touch in order to avoid a destabilizing effect on the biped motion. As the biped is essentially submitted to gravity forces, the motion is generated by minimizing the joint actuating torques. Feasible motions are defined by state inequality constraints limiting joint motions, and defining foot clearance and obstacle avoidance during the swing. The optimization problem is dealt with using Pontryagin's Maximum Principle. A final two-point boundary value problem is solved by implementing a shooting method. The approach presented is illustrated by various numerical simulations applying to a seven-body planar biped which has four or five active joints during the swing Phase.
-
Sagittal gait of a biped robot during the single Support Phase. Part 1: passive motion
Robotica, 2001Co-Authors: Mostafa Rostami, Guy BessonnetAbstract:The paper is aimed at generating optimal swing motions during the single-Support Phase of sagittal gait. Unlike the previous Part 1 which deals with passive motions, all joints of the biped are assumed to be active in the present Part 2. The final conditions specify an impactless heel-touch in order to avoid a destabilizing effect on the biped motion. As the biped is essentially submitted to gravity forces, the motion is generated by minimizing the joint actuating torques. Feasible motions are defined by state inequality constraints limiting joint motions, and defining foot clearance and obstacle avoidance during the swing. The optimization problem is dealt with using Pontryagin's Maximum Principle. A final two-point boundary value problem is solved by implementing a shooting method. The approach presented is illustrated by various numerical simulations applying to a seven-body planar biped which has four or five active joints during the swing Phase.
-
ICRA - Impactless sagittal gait of a biped robot during the single Support Phase
Proceedings. 1998 IEEE International Conference on Robotics and Automation (Cat. No.98CH36146), 1Co-Authors: Mostafa Rostami, Guy BessonnetAbstract:The problem of generating optimal sagittal reference gaits in bipedal walking is addressed. In our study the single-Support Phase during which the biped reaches its highest instability is considered. The approach developed allows for a fully dynamic model of the biped, and is based on minimizing the integral of quadratic joint actuating torques. Impactless and non-sliding heel-touch is accounted for, ensuring a more stable and easier controlled walking. Optimal motion synthesis is achieved by applying the Pontryagin maximum principle. Two numerical simulations are presented. Computed optimal motions reveal anthropomorphic gait characteristics.
Jong Hyeon Park - One of the best experts on this subject based on the ideXlab platform.
-
A Fast Turning Method for Biped Robots With Foot Slip During Single-Support Phase
IEEE ASME Transactions on Mechatronics, 2014Co-Authors: Je Sung Yeon, Jong Hyeon ParkAbstract:For a biped robot to have the capability to change the direction of locomotion fast without tripping itself is important in enhancing its mobility. This paper proposes a new method to realize a quick and natural turn, or to make an abrupt change in the walking direction of a biped robot by taking advantage of a foot slip, which is created intentionally between the sole of the foot and the ground. By using the slip at the Supporting foot, the robot can turn its body, in a single step, beyond the kinetic limit of its yaw joint. Thus, the proposed method makes it possible for the robot to make a single turning motion during the single-Support Phase in order to achieve a change in the locomotion that would not be possible unless the robot takes multiple steps. This reduces the time and the amount of space needed for a biped robot to make a turn. The mathematical conditions for a foot slip to occur are derived based on a simplified 3-D dynamic model of a biped robot consisting of three parts: a swing leg, a Supporting leg, and the rest of the body. Under these conditions, the desired translational and rotational trajectories for the swing foot and the main body are generated based on the expected floor surface condition. Computer simulations and experiments were carried out to prove the effectiveness of the proposed method for a quick and natural turn.
-
Humanoids - Quick change of walking direction of biped robot with foot slip in single-Support Phase
2011 11th IEEE-RAS International Conference on Humanoid Robots, 2011Co-Authors: Jin Tak Kim, Jong Hyeon ParkAbstract:This paper proposes a method to realize a quick and natural turn, or a change of the walking direction in the middle of locomotion of a biped robot, which takes advantage of a slip between the sole of the foot on the ground and the ground. The turn occurs during a single Support Phase to shortening the time to turn. Based on the 3D dynamics of a biped model which consists of one particle for a swing foot and a rigid body representing the main body of the robot, the desired trajectory of the swing foot and the expected friction on the ground, the desired ankle motion is computed. Simulations were performed with a 20-DOF biped robot model and the results of the simulations are described.
W.a. Gruver - One of the best experts on this subject based on the ideXlab platform.
-
ICRA - Trajectory synthesis and physical admissibility for a biped robot during the single-Support Phase
Proceedings. IEEE International Conference on Robotics and Automation, 1Co-Authors: C.-l. Shih, S. Churng, T.t. Lee, W.a. GruverAbstract:The synthesis and verification of biped walking trajectories during the single-Support Phase is discussed. The biped is modeled as a seven-link twelve degree-of-freedom anthropomorphic robot. By utilizing the zero moment point (ZMP) and the equivalent force-moment, the physical admissibility of the biped walking is characterized. For physically realizable walking during the single-Support Phase, the trajectory of the ZMP on the ground must be inside the stable region of the Supporting sole. A biped walking trajectory specified by eight pattern parameters is derived through inverse kinematics. ZMP trajectories for different walking patterns and the influence of the pattern parameters on the ZMP trajectories are presented. >
Mohammad Jafar Sadigh - One of the best experts on this subject based on the ideXlab platform.
-
Effect of Heel to Toe Walking on Time Optimal Walking of a Biped During Single Support Phase
Volume 3: Biomedical and Biotechnology Engineering, 2014Co-Authors: Tara Farizeh, Mohammad Jafar SadighAbstract:Dynamic modeling of a biped has gained lots of attention during past few decades. While stability and energy consumption were among the first issues which were considered by researchers, nowadays achieving maximum speed and improving pattern of motion to reach that speed are the important targets in this field. Walking model of bipeds usually includes two Phases, single Support Phase (SSP), in which only the stance foot is in contact with the ground while the opposite leg is swinging; and double Support Phase (DSP) in which the swing leg is in contact with the ground in addition to the rear foot. It is common in the simplified model of walking to assume the stance leg foot, flat during the entire SSP; but one may know that for human walking, there is also a sub-Phase during SSP in which the heel of stance foot leaves the ground while the whole body is Supported by toe link. Actually in this sub Phase the stance leg foot rotates around the toe joint. This paper is trying to study the effect of toe-link and heel to toe walking model on dynamic and specially speed of walking compare to flat foot model.Copyright © 2014 by ASME
-
ROBIO - Effect of increase in single Support Phase on walking speed of a biped robot
2011 IEEE International Conference on Robotics and Biomimetics, 2011Co-Authors: Tara Farizeh, Saeed Mansouri, Mohammad Jafar SadighAbstract:Fast motion of bipeds is an interesting subject for researchers. It is well known that for a specified biped, with certain physical parameters and actuation capability, change of kinematic parameters of motion may change the speed of motion. Among such parameters is the share of single Support Phase (SSP) in one complete step. This work presents a parameter study in which a Phase-plane analysis for minimum time motion of a biped is used to find maximum speed of biped for different values of SSP share in one step. A frame work is given for minimum time solution which fulfills zero moment point criteria for stability and friction condition for slippage prevention in addition to some kinematic constraints which guarantees normal pattern for walking. Parameter study is done through numerical simulation using the introduced algorithm.
