Mechanics analysis and predictive force models for the single-diamond grain grinding of carbon fiber reinforced polymers using CNT nano-lubricant

Mechanical behavior and semiempirical force model of aerospace aluminum alloy milling using nano biological lubricant

This paper presents a new robot for eye surgeries, referred to as DIAMOND. It consists of a spherical mechanism that has a remote center of motion (RCM) point and is capable of orienting the surgical instrument about this unique point. Using the RCM as the insertion point of the surgery instruments makes the robot suitable for minimally invasive surgery applications. DIAMOND has two pairs of identical spherical serial limbs that form a closed kinematic chain leading to high stiffness. The spherical structure of the mechanism is compatible with the human head and the robot may perform the surgery upon the head without any collision with the patient. Furthermore, dexterity and having a compact size is taken into account in the mechanical design of the robot. The workspace of the robot is a complete singularity free sphere that covers the region needed for any eye surgeries. In this paper, a comparison between different types of existing eye surgery robots is presented, the structure of the mechanism is described in detail and kinematic analysis of the robot is investigated.

Kinematic and workspace analysis of DIAMOND: An innovative eye surgery robot

Chatter in milling with robots with structural nonlinearity

An effect of hygrothermal effects on high velocity impact event for polymer matrix composites

Modeling and identification of cutting forces in milling of Carbon Fibre Reinforced Polymers

Online identification of mechanistic milling force models

Since rapid positioning and high accuracy is an important characteristic of closed-chain manipulators, the design of parallel manipulator should satisfy this performance. Dynamic analysis and optimization problem of a Spherical 3-DoF Parallel Manipulator (SPM) is the main subject of this paper. Based on Lagrange method, the closed-form dynamic formulation of the mechanism is investigated. Using jacobian and generalized inertia matrix, Global Dynamic Conditioning Index (GDCI) is proposed to evaluate the manipulator behavior in task space. Optimization procedure is formulated as maximization of GDCI, applying a simple genetic algorithm subjected to a set of appropriate constraints. So, a multi-criteria optimization analysis including both kinematics and dynamics behavior is considered on which achieving the largest workspace, fewest singularities and appropriate dynamic performance are available. Optimization results are used to have an optimum design of Agile-wrist mechanism that is represented in relevant tables and graphs.

Multi criteria design of a spherical 3-DoF parallel manipulator for optimal dynamic performance

This paper is devoted to dynamic formulation and motion control of a planar PRP parallel robot. Three intersecting rod comprises the manipulator of the mechanism which are fixed to each other and are coupled pivotedly to linear guides at the free ends. by actuating any of the linear guides along the sides of a triangle individually, the planar motion of the manipulator is provided. At first the kinematic and dynamic formulation of the mechanism is extracted in a closed form, which is of great interest in control applications. Based on the dynamic model, a computed torque control scheme is applied for the motion control of the robot. To analyze the performance of the controller it is implemented on a model of the mechanism made on simulation software for a predefined trajectory. The results of the motion tracking indicates the suitable performance of the implemented control scheme.

Dynamics formulation and motion control of a planar parallel manipulator

In this paper, a novel fuzzy model-based control scheme is presented for enhancing the controller performance in a complicated dynamical system of a 3-DoF spherical parallel manipulator. Firstly, the kinematics analysis and dynamics formulation of the robot are discussed briefly. Then, a fuzzy logic paradigm is utilized into a computed torque controller (CTC), which is implemented after extracting the kinematics and dynamics equations. This paradigm aims considerable decrease in settling time and damping the overshoot. Moreover, the designed controller satisfies the computational constraints for real-time implementation. A prototype has been manufactured for experimental studies in this work.

M. Farhadmanesh

Papers

Modeling and identification of cutting forces in milling of Carbon Fibre Reinforced Polymers

Online identification of mechanistic milling force models

Multi criteria design of a spherical 3-DoF parallel manipulator for optimal dynamic performance

Dynamics formulation and motion control of a planar parallel manipulator

Design of a new fuzzy model-based controller for complex dynamical systems with application to a 3-RRR spherical parallel manipulator