Passive dynamic walking is a gait developed, partially or in whole, by the energy provided by gravity. Research on passive dynamic bipedal walking helps develop an understanding of bipedal walking mechanics. Moreover, experimental passive dynamic research provides a base to compare and validate simulation results. An improved kneed bipedal walking mechanism and an improved measurement system are used to study the passive gait patterns. Gait measurements are conducted on the treadmill to evaluate the effects of the treadmill angle of inclination, mass distribution of the biped, treadmill belt speed, length of flat feet and thigh-shank length on the gait patterns. Most of these dynamic and geometric parameters have significant effects on step length, step period and robustness of the passive gait. Difficulties have been faced with the study of the flat feet and the leg length variation. Suggestions have been provided for future work. Experimental results are compared with previous work based on both the experimental and the computer simulation.

Passive dynamic walking is a gait developed, partially or in whole, by the energy provided by gravity. Research on passive dynamic bipedal walking helps develop an understanding of bipedal walking mechanics. Moreover, experimental passive dynamic research provides a base to compare and validate simulation results. An improved kneed bipedal walking mechanism and an improved measurement system are used to study the passive gait patterns. Gait measurements are conducted on the treadmill to evaluate the effects of the treadmill angle of inclination, mass distribution of the biped, treadmill belt speed, length of flat feet and thigh-shank length on the gait patterns. Most of these dynamic and geometric parameters have significant effects on step length, step period and robustness of the passive gait. Difficulties have been faced with the study of the flat feet and the leg length variation. Suggestions have been provided for future work. Experimental results are compared with previous work based on both the experimental and the computer simulation.

This work deals with automatic generation of hybrid dynamics of bipedal robot in Matlab symbolic toolbox. Next goal is to provide linearisation of nonlinear model and achieve optimal state space controller. Work implements object model generator and simulator based on core of Matlab Simulink and visualisation of the results in user friendly GUI.

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Bipedal locomotion is a challenging control engineering problem due to the non-linear dynamics and postural instability of the bipedal form. In addition to these challenges, some dynamical effects such as the ground reaction force are difficult to model accurately in simulation. To this end, it is essential to develop physical hardware to validate walking control strategies and gait generation methods. This thesis develops an on-line walking control strategy for humanoid robots and the electromechanical design of a physical platform for experimental validation. The first part of the thesis presents the development of a 14 degrees-of-freedom (DOF) lower body humanoid robot. The initial electromechanical design of the proposed system is derived from dynamic modeling of a general multibody system. Kinematic trajectories for the lower body joints are extracted from motion captured human gait data to form the preliminary design specifications. The drivetrain components are selected by analyzing the mechanical power requirements, torque-speed profiles, efficiency and thermal characteristics of actuators. The supporting mechanical chassis and power transmission system are designed to raise the center-of-mass (to reduce the swinging inertia of each leg) while minimizing the overall weight of the system. Refining the design of a complex multibody robotic system like the biped is an iterative process. The mechanical model of the system is transferred from Computer-Aided-Design (CAD) software to a dynamic simulator for analysis and the design is revised to improve performance. This iterative approach is necessary as small changes in the mechanical model can have significant impact on the overall dynamics of the system as well as implications for control design. A streamlined prototyping toolchain is developed in this thesis to extract the relevant kinematic/dynamic parameters of a mechanical system in CAD and automatically generate the equivalent system in a dynamic simulator. This toolchain is used to revise the electromechanical design and generate forward dynamics simulations. The second portion of this thesis develops a novel walking control strategy for on-line gait synthesis for 3D bipedal robots based on Wight's Foot Placement Estimator (FPE) algorithm. This algorithm is used to determine the desired swing foot position on the ground to \emph{restore} balance for a 2D bipedal robot. The FPE algorithm is extended to the general 3D case by selecting a suitable plane in the desired direction of motion. Complete gait cycles are formed by combining a finite state machine with the 2D FPE solution along the selected plane. Gait initiation is accomplished by computing state-dependent task space trajectories on-line to produce a forward momentum along the selected plane. A whole-body motion control framework (Jacobian-based prioritized task space control scheme) tracks the task space trajectories and generates the appropriate joint level command for each state. The joint level commands are tracked by local high gain PD controllers. This framework produces the desired whole-body motion during each state while satisfying higher priority constraints. Gait termination is accomplished by controlling the swing foot position to track the FPE point on the ground along the selected plane. The proposed control strategy is verified in simulation and experiments. A parallel hardware-in-the-loop (HIL) testing environment is developed for the physical lower body humanoid robot. The motion control framework and joint dynamics used in the proposed walking control strategy are verified through HIL experiments.

The locomotion robots have wheeled, biped, quadruped and so on. Walking robot may not move faster or more popular than wheeled robot. But walking robot is a good assistant to pass through the rough roadway and to explore unknown landforms. The advantages of walking robot have: mobility, walking in danger environment, across obstacles, up stairs and down stairs and nimbleness. These difficulties environment are the obstacles for the wheeled robot. Today, many robots are designed to make up for human body and ability. Application in explore the outer space, to relieve the victims of a disaster, to move work, to offer greater convenience to the people, housekeeper, to substitute for handicapped limbs and so on. In the thesis, we analyze the gait of biped robot. Biped robot arrive a destination rapidly in the limit environment. Biped can use turning motion gait to bypass obstacles. We purpose to maintain motion velocity of biped robot and come out the speed and stride distance of the biped robot. The studies have: biped robot turning design, planning humanoid motion gait and experiment motion gait.

Biped walking remains a difficult problem and robot models can greatly {facilitate} our understanding of the underlying biomechanical principles as well as their neuronal control. The goal of this study is to specifically demonstrate that stable biped walking can be achieved by combining the physical properties of the walking robot with a small, reflex-based neuronal network, which is governed mainly by local sensor signals. This study shows that human-like gaits emerge without {specific} position or trajectory control and that the walker is able to compensate small disturbances through its own dynamical properties. The reflexive controller used here has the following characteristics, which are different from earlier approaches: (1) Control is mainly local. Hence, it uses only two signals (AEA=Anterior Extreme Angle and GC=Ground Contact) which operate at the inter-joint level. All other signals operate only at single joints. (2) Neither position control nor trajectory tracking control is used. Instead, the approximate nature of the local reflexes on each joint allows the robot mechanics itself (e.g., its passive dynamics) to contribute substantially to the overall gait trajectory computation. (3) The motor control scheme used in the local reflexes of our robot is more straightforward and has more biological plausibility than that of other robots, because the outputs of the motorneurons in our reflexive controller are directly driving the motors of the joints, rather than working as references for position or velocity control. As a consequence, the neural controller and the robot mechanics are closely coupled as a neuro-mechanical system and this study emphasises that dynamically stable biped walking gaits emerge from the coupling between neural computation and physical computation. This is demonstrated by different walking experiments using two real robot as well as by a Poincar\' map analysis applied on a model of the robot in order to assess its stability. In addition, this neuronal control structure allows the use of a policy gradient reinforcement learning algorithm to tune the parameters of the neurons in real-time, during walking. This way the robot can reach a record-breaking walking speed of 3.5 leg-lengths per second after only a few minutes of online learning, which is even comparable to the fastest relative speed of human walking.

Passive dynamic walking is a manner of walking developed, partially or in whole, by the energy provided by gravity. Studying passive dynamic walking provides insight into human walking and is an invaluable tool for designing energy efficient biped robots. The objective of this research was to develop a new mathematical model of passive dynamic walking that modeled the ground reaction forces. A physical passive walker was built to validate the proposed mathematical model. The stability of the gait was analyzed using the proposed model. A novel method was created to determine the stability region of the model. Using the insights gained from the stability analysis, the relation between the angular momentum and the stability of the gait was examined. The proposed model matched the gait of the physical passive walker exceptionally well, both in trend and magnitude. The angular momentum of the passive walker was not found to correlate to the stability of the gait.

Passive dynamic walking is a manner of walking developed, partially or in whole, by the energy provided by gravity. Studying passive dynamic walking provides insight into human walking and is an invaluable tool for designing energy efficient biped robots. The objective of this research was to develop a new mathematical model of passive dynamic walking that modeled the ground reaction forces. A physical passive walker was built to validate the proposed mathematical model. The stability of the gait was analyzed using the proposed model. A novel method was created to determine the stability region of the model. Using the insights gained from the stability analysis, the relation between the angular momentum and the stability of the gait was examined. The proposed model matched the gait of the physical passive walker exceptionally well, both in trend and magnitude. The angular momentum of the passive walker was not found to correlate to the stability of the gait.

Bipedal locomotion is a challenging control engineering problem due to the non-linear dynamics and postural instability of the bipedal form. In addition to these challenges, some dynamical effects such as the ground reaction force are difficult to model accurately in simulation. To this end, it is essential to develop physical hardware to validate walking control strategies and gait generation methods. This thesis develops an on-line walking control strategy for humanoid robots and the electromechanical design of a physical platform for experimental validation. The first part of the thesis presents the development of a 14 degrees-of-freedom (DOF) lower body humanoid robot. The initial electromechanical design of the proposed system is derived from dynamic modeling of a general multibody system. Kinematic trajectories for the lower body joints are extracted from motion captured human gait data to form the preliminary design specifications. The drivetrain components are selected by analyzing the mechanical power requirements, torque-speed profiles, efficiency and thermal characteristics of actuators. The supporting mechanical chassis and power transmission system are designed to raise the center-of-mass (to reduce the swinging inertia of each leg) while minimizing the overall weight of the system. Refining the design of a complex multibody robotic system like the biped is an iterative process. The mechanical model of the system is transferred from Computer-Aided-Design (CAD) software to a dynamic simulator for analysis and the design is revised to improve performance. This iterative approach is necessary as small changes in the mechanical model can have significant impact on the overall dynamics of the system as well as implications for control design. A streamlined prototyping toolchain is developed in this thesis to extract the relevant kinematic/dynamic parameters of a mechanical system in CAD and automatically generate the equivalent system in a dynamic simulator. This toolchain is used to revise the electromechanical design and generate forward dynamics simulations. The second portion of this thesis develops a novel walking control strategy for on-line gait synthesis for 3D bipedal robots based on Wight's Foot Placement Estimator (FPE) algorithm. This algorithm is used to determine the desired swing foot position on the ground to \emph{restore} balance for a 2D bipedal robot. The FPE algorithm is extended to the general 3D case by selecting a suitable plane in the desired direction of motion. Complete gait cycles are formed by combining a finite state machine with the 2D FPE solution along the selected plane. Gait initiation is accomplished by computing state-dependent task space trajectories on-line to produce a forward momentum along the selected plane. A whole-body motion control framework (Jacobian-based prioritized task space control scheme) tracks the task space trajectories and generates the appropriate joint level command for each state. The joint level commands are tracked by local high gain PD controllers. This framework produces the desired whole-body motion during each state while satisfying higher priority constraints. Gait termination is accomplished by controlling the swing foot position to track the FPE point on the ground along the selected plane. The proposed control strategy is verified in simulation and experiments. A parallel hardware-in-the-loop (HIL) testing environment is developed for the physical lower body humanoid robot. The motion control framework and joint dynamics used in the proposed walking control strategy are verified through HIL experiments.