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The purpose of this paper is to design an electromechanical actuator which can inherently tolerate a stuck or loose failure without any need for fault detection isolation and reconfiguration.

Generalized design methodology for a thrust vector control application is adopted to reduce the design iterations during the initial stages of the design. An optimum ball screw pitch is selected to minimize the motor sizing and maximize the load acceleration.

A high redundancy electromechanical actuator for thrust vector control has lower self-inertia and higher reliability than a direct drive simplex configuration. This configuration is a feasible solution for thrust vector control application because it offers a more acceptable and graceful degradation than a complete failure.

Future work will include testing on actual hardware to study the transient disturbances caused by a fault and their effect on launch vehicle dynamics.

High redundancy electromechanical actuator concept can be extended to similar applications such as solid motor nozzle in satellite launch vehicles and primary flight control system in aircraft.

High redundancy actuators can be useful in safety critical applications involving human beings. It can also reduce the machine downtime in industrial process automation.

The jam tolerant electromechanical actuator proposed for the launch vehicle application has a unique configuration which does not require a complex fault detection isolation and reconfiguration logic in the controller. This enhances the system reliability and allows a simplex controller having a lower cost.

This paper aims to describe how a novel biomimetic chewing robot was designed, including its motion, force, control and mechanical designs, and shows some initial experiments about motion tracking.

According to the biomechanics, the authors modeled the muscles of mastication in six linkages and the temporomandibular joint in higher kinematic pairs of point contact. As a result, the chewing robot was represented in a redundantly actuated parallel mechanism. With reference to literature data on the biological system, the authors specified the motion and force requirements for the robot via inverse kinematics and force analysis. A prototype of the robot was built, which has a position control system and is driven by six linear actuators. Experiments were conducted to show the capability of the robot in reproducing the human chewing motion.

A chewing robot was successfully modeled and developed, which is able to simulate the motion of human mastication in a biologically faithful way.

The chewing robot as a scientific instrument can be used to test dental materials and evaluate food textural properties of chewing.

Two higher kinematic pairs of point contact are proposed to simulate the two temporomandibular joints. The mechanism of the novel chewing robot is the first of this kind, which has two higher kinematic pairs of point contact and is a redundantly actuated spatial parallel mechanism.

This paper aims to verify the workspace and movement performance of a redundantly actuated humanoid chewing robot.

A redundantly actuated humanoid chewing robot with 6-PUS linkages and two higher kinematic pairs (HKPs) is introduced. The design of HKPs is specified by mimicking the temporomandibular joint (TMJ) structure obtained through a computed tomography scan of the mastication system. The border movement, mouth-opening trajectory and velocity of subjects’ lower incisor point are measured by using the mandibular kinesiograph. Based on the kinematics, the envelope of the workspace is analyzed. The workspace and mouth-opening movement experiments are carried out. The border movement of the lower incisor point is measured. The mouth-opening trajectory is planned and tested on the chewing robot.

Comparing with measurement results of border movement and mouth-opening movement of human, it is shown that the humanoid chewing robot can meet the workspace requirements and is able to perform mouth-opening movement like human-beings.

The chewing robot is designed to reproduce human jaw movements and application in test of dental components and materials or evaluation of food textural properties.

The chewing robot is inspired by the mastication system which itself is mechanically redundant because of the TMJ and more muscles than required. The novel spatial redundantly actuated chewing robot is the first of this kind with two HKPs to mimic the human TMJ and is a higher fidelity mechanism.

An optimal solution method based on 2-norm is proposed in this study to solve the inverse kinematics multiple-solution problem caused by a high redundancy. The current research also presents a motion optimization based on the 2-Norm of high-redundant mobile humanoid robots, in which a kinematic model is designed through the entire modeling.

The current study designs a highly redundant humanoid mobile robot with a differential mobile platform. The high-redundancy mobile humanoid robot consists of three modular parts (differential driving platform with two degrees of freedom (DOF), namely, left and right arms with seven DOF, respectively) and has total of 14 DOFs. Given the high redundancy of humanoid mobile robot, a kinematic model is designed through the entire modeling and an optimal solution extraction method based on 2-norm is proposed to solve the inverse kinematics multiple solutions problem. That is, the 2-norm of the angle difference before and after rotation is used as the shortest stroke index to select the optimal solution. The optimal solution of the inverse kinematics equation in the step is obtained by solving the minimum value of the objective function of a step. Through the step-by-step cycle in the entire tracking process, the kinematic optimization of the highly redundant humanoid robot in the entire tracking process is realized.

Compared with the before and after motion optimizations based on the 2-norm algorithm of the robot, its motion after optimization shows minimal fluctuation, improved smoothness, limited energy consumption and short path during the entire mobile tracking and operating process.

In this paper, the whole kinematics model of the highly redundant humanoid mobile robot is established and its motion is optimized based on 2-norm, which provides a theoretical basis for the follow-up research of the service robot.

In this paper, the whole kinematics model of the highly redundant humanoid mobile robot is established and its motion is optimized based on 2-norm, which provides a theoretical basis for the follow-up research of the service robot.

In this paper, the whole kinematics model of the highly redundant humanoid mobile robot is established and its motion is optimized based on 2-norm, which provides a theoretical basis for the follow-up research of the service robot.

Motion optimization based on the 2-norm of a highly redundant humanoid mobile robot with the entire modeling is performed on the basis of the entire modeling. This motion optimization can make the highly redundant humanoid mobile robot’s motion path considerably short, minimize energy loss and shorten time. These researches provide a theoretical basis for the follow-up research of the service robot, including tracking and operating target, etc. Finally, the motion optimization algorithm is verified by the tracking and operating behaviors of the robot and an example.

Outlines the methods and costs of converting existing robotic systems to new applications and gives research results of software and hardware conversion strategies which speed up re‐configuration. Discusses the trade‐offs between buying new solutions or upgrading old ones, describes the uses and extra costs of multi‐arm systems and attempts to generalize the applications to which they can be put. Concludes that the application of co‐operating, multi‐arm systems can provide high system reusability, although this is at the cost of greater planning needs, some of which have been met. Continued enhancement of processing power, sensing and operator interfaces are permitting multi‐arm systems to be used and reused in versatile, high dexterity industrial applications.

The paper aims to address the combined attitude control and Sun tracking problem in a flexible spacecraft in the presence of external and internal disturbances. The attitude stabilization of a flexible satellite is generally a challenging control problem, because of the facts that satellite kinematic and dynamic equations are inherently nonlinear, the rigid–flexible coupling dynamical effect, as well as the uncertainty that arises from the effect of actuator anomalies.

To deal with these issues in the combined attitude and Sun tracking system, a novel control scheme is proposed based on the adaptive fuzzy Jacobian approach. The augmented spacecraft model is then analyzed and the Lyapunov-based backstepping method is applied to develop a nonlinear three-axis attitude pointing control law and the adaptation law.

Numerical results show the effectiveness of the proposed adaptive control scheme in simultaneously tracking the desired attitude and the Sun.

Reaction wheels are commonly used in many spacecraft systems for the three-axis attitude control by delivering precise torques. If a reaction wheel suffers from an irreversible mechanical breakdown, then it is likely going to interrupt the mission, or even leading to a catastrophic loss. The pitch-axis mounted solar array drive assemblies (SADAs) can be exploited to anticipate such situation to generate a differential torque. As the solar panels are rotated by the SADAs to be orientated relative to the Sun, the pitch-axis wheel control torque demand can be compensated by the differential torque.

The proposed Jacobian control scheme is inspired by the knowledge of Jacobian matrix in the trajectory tracking of robotic manipulators.

The robot offers interesting capabilities, but suffers from a lack of stiffness. The proposed solution is to introduce redundancies for the overall improvement of different capabilities. The management of redundancy associated with the definition of a set of kinematic, mechanical and stiffness criteria enables path planning to be optimized.

The resolution method is based on the projection onto the kernel of the Jacobian matrix of the gradient of an objective function constructed by aggregating kinematic, mechanical and stiffness weighted criteria. Optimized redundancy management is applied to the 11-DoF (degrees of freedom) cells to provide an efficient placement of turntable and track. The final part presents the improvement of the various criteria applied to both 9-DoF and 11-DoF robotic cells.

The first application concerns the optimized placement of a turntable and a linear track using 11-DoF architecture. Improved criteria for two 9-DoF robotic cells, a robot with parallelogram closed loop and a Tricept are also presented. Simulation results present the contributions of redundancies and the leading role of the track.

The redundancy-based optimization presented and the associated simulation approach must be completed by the experimental determination of the optimization criteria to take into account each machining strategy.

This work in robotics machining relates to milling operations for automotive and aerospace equipment. The study is carried out within the framework of the RobotEx Equipment of Excellence programme.

The resolution method to optimized path planning is applied to 9- and 11-DoF robotic cells, including a hybrid robot with a parallelogram closed loop and a Tricept PKM.

The purpose of this paper is to present a new method to establish a kinematic model for a continuum manipulator, whose end can be controlled to move in a three-dimensional workspace. A continuum manipulator has significant advantages over traditional, rigid manipulators in many applications because of its ability to conform to the environment. Moreover, because of its excellent flexibility, light weight, low energy consumption, low production cost, it has a number of potential applications in areas of earthquake relief, agricultural harvesting, medical facilities and space exploration.

This paper uses basic theory of material mechanics to deduct motion equations of the manipulator. Unlike other published papers, the manipulator is not based on segments tactics, but regarded as an integrated flexible system, which simplifies its kinematics modelling and motion controlling. The workspace of the manipulator is analysed by theoretical deducing and simulation modelling. For verification of the presented theory, simulation based on ADAMS software was implemented, while a prototype of the manipulator was developed. Both the software simulation and prototype experiment show that the theoretical analysis in this paper is reasonable. The manipulator can move accurately along the desired trajectories.

This paper developed a novel and fully continuous manipulator driven by steel wires. A kinematic model of the manipulator was established. The physical manipulator developed for verifying the kinematic model can effectively track the prescribed trajectory. The presented kinematic model agrees with not only the simulation but also with the experiment.

The manipulator presented in this paper is constructed by steel wires. It possesses the advantages of structural continuity, high flexibility and low production cost. It can be extensively used in many fields, such as search and rescue robotic systems. The limitation of this research is that the dynamic model of the manipulator is not yet clear, which is one of the directions for future research.

The manipulator breaks through the limitation of the joint-type or flexible-link-type manipulator, which can also be extensively used in many fields such as search and rescue robotic systems.

The manipulator developed in this paper, currently, is a prototype under the project of “Automatic Picking Manipulator Research”. It possesses a good market value.

The value of this research is that the manipulator breaks through the limitation of the joint-type or flexible-link-type manipulator and establishes the kinematic model for a fully continuous manipulator by a simple strategy. This is the first study that uses such a strategy for establishing the motion equations of a monolithic continuum manipulator.

Reports on the UK Mechatronics Forum Conference held in Minho, Portugal, in September 1996. Outlines the major themes and focuses on those papers most relevant to industrial robotics, giving brief details of the content of the papers.

The paper aims to achieve translational shaking tests on a 6-DOF hydraulic parallel manipulator. Shaking tests are commonly performed on shaking tables, which are generally used for small motion ranges and are usually financially costly. The research is required to generate shaking motions in three translational directions for a specimen for shaking tests, but it also needs to produce 6-degree of freedom (DOF) motions with large motion ranges.

A hydraulic 6-DOF (degree of freedom) parallel manipulator is applied to achieve this goal. The link-space control is adopted for the manipulator, and PID controller and feed-forward controller are used for each loop of the system. A hybrid reference signal generator is proposed by using a shaking controller, which is developed to convert the shaking motion into position signal. The converted result is directly added to the pose signal. The whole real-time control system is realized by using MATLAB xPC Target.

The developed method is verified on the hydraulic 6-DOF parallel manipulator with specimen. Experiments show very promising results that the proposed technology is really applicable to perform translational shaking tests on the hydraulic parallel manipulator.

A simple yet efficient solution is proposed that allows shaking tests in three translational directions performed on the hydraulic 6-DOF parallel manipulator with wide motion ranges. The paper presents a state-of-the-art related to the applications of parallel robots in several fields of technology.