Preface

Kinematics deals with changes of position (motion, displacement, velocity, acceleration, etc.) and/or geometry (strain, strain rate, volume, etc.), without being concerned with the causes of these changes (forces, torques, etc.). Numerous problems in engineering and biology can be described, formulated, characterized, and analyzed in kinematics terms.

In classical machinery and robotics the most distinctive characteristic is constrained motion of interconnected parts relative to one another. Thus, multi-degree-offreedom kinematic chains, robotic arms, and manipulators have become essential devices in industrial applications, including manufacturing, vehicle, space, agriculture, military, and medicine. Impressive recent developments in medical robotics have included surgical robots and robots for aiding persons with disabilities. Miniaturization has led to nano-manipulators and robots. Kinematics is also used as a basis for designing sensors such as displacement transducers, accelerometers, gyroscopes, and strain gauges.

In biological organs kinematics serves to describe motion, deformation, or both. Multi-segment representation of the human body, with the segments usually treated as rigid bodies, enables to describe sets of movements, including standing, walking, running, and jumping. More recent analyses have extended the multi-segment representation to express effects of wobbling mass due to influence of the soft internal organs in the limbs, abdomen, chest, skull, and the like. Kinematics of deformable bodies, such as the beating heart or uterus under labor contractions, can be expressed in terms of strain, geometric curvature, and local obliqueness, providing essential information about the deforming organ. At the micro level, kinematics is being applied in investigations of cellular response (motion and deformation) through mechanical changes induced to the medium in which the cells are being cultured.

This book provides the reader with an updated look at the current trends in kinematics methods and applications. It comprises of three sections. The first section deals with kinematics of linkages and includes analysis of cam mechanisms, kinematic pairs, and transformation of rotary motion into oscillation. The second section covers compliant mechanisms, whereby elastically deformable parts rather than conventional joints are part of the mechanism. The third section deals with kinematics of spacecrafts and satellites in the contexts of global navigation systems as well as space robot analysis using forward and inverse kinematics.

> **Joseph Mizrahi** Professor Department of Biomedical Engineering Technion, Israel Institute of Technology, Haifa, Israel

Section 1

Kinematics of Linkages

1

Section 1
