Purpose: This study aimed to investigate excursion changes at the hip, knee, and ankle joints during gait in patients with knee osteoarthritis (KOA) of varying severity. Methods: The method of research was causal-comparative (Ex Post Facto). A Vicon motion analysis system with 4 T-Series cameras was used to measure the kinematics variables. Fifteen normal subjects without KOA and thirty patien...

In this paper, we investigate the task-space consensus problem for multiple robotic systems with both the uncertain kinematics and dynamics in the case of existence of constant communication delays. We propose an observer-based adaptive controller to achieve the manipulable consensus without relying on the measurement of task-space velocities, and also formalize the concept of manipulability to...

In this paper, we propose a robust control framework for object manipulation for when the robotic hand has limited knowledge of the grasp scenario. The framework considers a hand-object system subject to disturbances resulting from uncertainties in the object center of mass/inertia, hand kinematics, external wrenches, and contact locations. The framework guarantees semi-global asymptotic stabil...

We present a high resolution, SparsePak two-dimensional velocity field for the center of the low surface brightness (LSB) galaxy DDO 39. These data are a significant improvement on previous H I or Hα long slit data, yet the inner rotation curve is still uncertain due to significant noncircular and random motions. These intrinsic uncertainties, probably present in other LSB galaxies too, result ...

In this paper, we investigate the visual tracking for robotic systems without visual velocity measurement, simultaneously taking into account the uncertain depth information, the kinematic and the dynamic uncertainties. We propose a new image-space observer that exploits the image-space velocity information contained in the unknown kinematics, upon which, we design an adaptive controller withou...

We report on a study of the time sequence for the appearance of highvelocity jets and equatorial tori in the transition of stars from the asymptotic giant branch to the planetary nebulae phase. Jets and tori are prominent features of this evolution, but their origins are uncertain. Using the kinematics of molecular tori and molecular or optical jets, we determine the ejection histories for a sa...

Autonomous wheeled skid-steering mobile robot off-road trajectory tracking is focused on. According to the kinematics and dynamics analysis of the robot, a constraint of the robot motion is put forward. As uncertain disturbance factors exist during the robot off-road running, a novel fuzzy lateral control law is proposed, which makes the robot motion globally asymptotically stable. According to...

Robot systems in critical applications, such as those in space and nuclear environments, must be able to operate during component failure to complete important tasks. One failure mode that has received little attention is the failure of joint position sensors. Current fault tolerant designs require the addition of directly redundant position sensors which can affect joint design. The proposed m...

Abstract: An adaptive neural network controller is proposed to deal with the end-effector tracking problem of manipulators with uncertainties. By employing the adaptive Jacobian scheme, neural networks, and backstepping technique, the torque controller can be obtained which is demonstrated to be stable by the Lyapunov approach. The updating laws for designed controller parameters are derived by...

An adaptive impedance control algorithm for tendon-driven dexterous hands is presented. The main idea of this algorithm is to compensate the output of the classical impedance control by an offset that is a proportion-integration-differentiation (PID) expression of force error. The adaptive impedance control can adjust the impedance parameters indirectly when the environment position and stiffne...