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We present a hierarchical controller for a set of two linear synchronous motors with permanent magnets moving in two orthogonal directions for a two degree of freedom high-precision positionning system developed by Newport-France. This system is supposed to realize relatively fast linear displacements from 1 count (4 nm) to 400 mm. A linear displacement of 25mm must be achieved in less than 0.2 s...
This paper presents the performance validation of the motion control system for integration force and trajectory information. To realize the implementation high-quality motion that includes contact and non-contact motion to robot system, two contradictory systems; force and trajectory control should be synthesized in one control axis. In order to respond to the request, we proposed a motion synthesis...
Several algorithms have been proposed in the last 25 years on the problem of generating time-optimal trajectories for robot manipulators along specified paths. This article describes an application of an optimal trajectory algorithm to an industrial manipulator used in the transfer of solar panel substrates between process modules. These manipulators operate in a vacuum environment and have constraints...
A pursuer UAV tracking and loitering around a target is the problemanalyzed in this work. The UAV is assumed to be a fixed-wing vehicle and constant airspeed together with bounded lateral accelerations are the main constraints of the problem. The pursuer motion control law proposed in this paper is based on the definition of an oscillatory motion created by a center of oscillation: it allows the pursuer...
In this paper, a new approach to identify the parameters of robot manipulator dynamics is presented. The approach is based on exciting the robot manipulator with multiple identification trajectories that pass through the operating point with specific speeds and accelerations. The position, velocity and acceleration of the robot joints along with the corresponding torque at the operating point are...
In generating walking patterns for humanoid robots, a Center-of-Mass trajectory is usually derived from the desired Zero-Moment-Point (ZMP) trajectory. One way to accomplish this is the use of the preview-control method, which tracks the desired ZMP trajectory while minimizing the jerk. Another method, which is more computationally efficient, is based on the convolution-sum method. Although this method...
Many tracking problems are split into two sub-problems, first a smooth reference trajectory is generated that meet the control design objectives, and then a closed loop control system is designed to follow this reference trajectory as well as possible. Applications of this kind include (autonomous) vehicle navigation systems and robotics. Typically, a spline model is used for trajectory generation...
This paper deals with the trajectory planning of a full-rotate parallel robot for wafer transfer operations. With the path length in work space of the robot as parameter, the dynamic model is parameterized. The system constraints-input torque and velocity constraints and the task constraints-output velocity, acceleration, and jerk limits are set; with the minimized operation time as the optimization...
The paper deals with modeling of human-like reaching movements. Several models are under study. First, we consider a model of reaching movement that corresponds to the minimization of control effort. It is shown that this model is represented by the well-known Beta function. The representation can be used for the construction of fractional order models and also for modeling of asymmetric velocity...
This paper presents a method for mapping captured human motion with stepping to a humanoid model, considering the current state and the controller behavior. The mapping algorithm modifies the joint angle, trunk and center of mass (COM) trajectories so that the motion can be tracked and desired contact states can be achieved. The mapping is performed in two steps. The first step modifies the joint...
In this paper, a trajectory generator based on causal modeling is presented. This strategy is applied to the velocity constraint trajectory generation of an automatic subway. The constraints take into account of passengers comfort by the use of imposed maximum jerk and acceleration values. The proposed velocity generator is enhanced by the use of torque model of the DC machines. The proposed velocity...
This paper deals with time-optimization of trajectories of wheeled robots within the speed and other constraints. The cubic Hermite spline curve with the method of speed profile computation is used to determine the trajectory. This method is summarized and extended to allow the optimization with the described constraints. It ensures fulfilment of required initial parameters of motion. The parameters...
We tackle the problem of trajectory control of a four-wheel driven skid-steering (4WDSS) robotic platform with asynchronous wheels velocity. A practical mathematical formulation for solving inverse and direct kinematics is provided. This approach also includes the formulation and implementation of a home made arrange of accelerometers to infer robot displacements in global coordinates system. Although...
In order to solve the vibration during the process of transferring wafers and achieve the purpose of transferring wafers accurately and stably, the wafer transfer robot dynamic model was modelled and the strategy of vibration suppression based on input shaping was proposed. Based on the characteristics of wafer transfer robot, ZV input shaper and skewed shaper was designed to solve the single axis's...
A filter for trajectories smoothing is presented. The filter provides an output reproducing the input trajectory if this is compliant with given constraints on the velocity, the acceleration and the torque required for tracking it. Otherwise, the filter approximates the input profile guaranteeing that the output trajectory satisfies all the kinematic and dynamic limits. The tracking of the input signal...
The present paper proposes the throwing manipulation method which cannot only control the position and orientation of the rigid object at the final goal, but also make the object track the desired trajectory which minimizes the impact at landing to avoid damages to the object as much as possible. Due to a model uncertainty, it is generally difficult to obtain the exact model and find appropriate control...
A strategy for trajectory design, motion camouflage, is introduced within the context of orbital relative motion. At first the equations of orbital motion for this approach are developed. The control strategy is then implemented using both an impulsive and continuous approach. A number of parameters are then optimized to minimize the fuel mass. The simulation results reveal that the predator successfully...
The issue of satellite operations in close proximity to a reference satellite is of interest for both civilian and military applications. One such operation is fast fly around formation in a time period less than the orbital period of the reference satellite. A control law based on continuous low thrust is derived in this paper to realize fast fly around space circle formation on circular orbit. The...
In the entry phase, aero-environment is extremely complex for Reusable Launch Vehicles (RLVs). This brings a huge challenge to design the entry guidance law for RLVs. In this paper, an entry trajectory planning method for RLVs is researched and the algorithm is improved to ensure the continuity and smoothness of the longitudinal reference trajectory. Meanwhile, the skipping of trajectory control is...
Relative coordination has predominant advantage in uncertain environment path planning problem because it denies much of redundant information of the dynamic environment while avoids the rotation transformation which is a big burden in the traditional methods. Based on relative coordination, this paper proposes a trimmed Ant Colony Optimization (ACO) algorithm for three dimensional trajectory generation,...
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