The paper considers the behavior of redundant manipulators which collide with an obstacle and the obstacle avoidance after the collision. Without changing the motion of the end-effector, the reconfiguration of the manipulator into a collision-free configuration can be done only by utilizing the self-motion of the manipulator. In the paper some motion controllers are analyzed which minimize the ...

Continuum manipulators such as robotic tele-operated cardiac catheters continue to gain popularity for use in minimally invasive surgical procedures due to their inherent safety characteristics. However, their flexible nature makes them prone to both steady state positioning errors and undesirable vibrations. We propose a combined control system incorporating both a tracking position controller...

In this paper we present a new, and extremely fast, algorithm for the inverse kinematics of discretely actuated manipulator arms with many degrees of freedom. Our only assumption is that the arm is macroscopicallyserial in structure,meaning that the overall structure is a serial cascade of units with each unit having either a serial or parallel kinematic structure. Our algorithm builds on previ...

In this paper, we study continuous path operation of a 3-RRR planar parallel manipulator whose joints have clearance. During continuous path operation end-effector must go through a predefined path. However, clearance introduces an additional uncontrollable degree of freedom to the manipulator. Therefore it causes error and should not be neglected in a successful path operation. In this paper, ...

This paper presents experimental investigations into the applications of feedforward control schemes for vibration control of a flexible manipulator system. Feedforward control schemes based on input shaping and filtering techniques are to be examined. A constrained planar single-link flexible manipulator is considered in this experimental work. An unshaped bang-bang torque input is used to det...

This paper presents the position control of a 3-DOF 3-RRR planar parallel manipulator by using the model predictive control. Not only the numerical simulations are demonstrated but also an experimental hardware-in-the-loop system is constructed. The experimental results are used to verify the simulation results. The entire system is designed as a semi-closed loop system. The manipulator is driv...

This article presents the development of an autonomous motion planning algorithm for a soft planar grasping manipulator capable of grasp-and-place operations by encapsulation with uncertainty in the position and shape of the object. The end effector of the soft manipulator is fabricated in one piece without weakening seams using lost-wax casting instead of the commonly used multilayer laminatio...

The UDUT – U and D are respectively the upper triangular and diagonal matrices – decomposition of the generalized inertia matrix of an n-link serial manipulator, introduced elsewhere, is used here for the simulation of industrial manipulators which are mainly of serial type. The decomposition is based on the application of the Gaussian elimination rules to the recursive expressions of the eleme...

• Non-linear dynamics modelling description for simulating the behaviour of forestry cranes 2014 • Modeling an industrial flotation process: A case study at the mining company Boliden AB 2012 • Modeling dynamics of an electro-hydraulic servo actuated manipulator: A case study of a forestry forwarder crane 2012 • Underactuated mechanical systems: Contributions to trajectory planning, analysis, a...

The application of quadratic optimization and sliding-mode approach is considered for hybrid position and force control of a robot manipulator. The dynamic model of the manipulator is transformed into a state-space model to contain two sets of state variables, where one describes the constrained motion and the other describes the unconstrained motion. The optimal feedback control law is derived...