robotics
Chapter 1
Preview
Robotics is a relatively young subject that has set itself the rather ambitious– some would say impossible–goal of trying to create intelligent, physical machines that think and behave like humans. This attempt to create intelligent machines naturally leads us to first examine ourselves, to ask, for example, why our bodies are designed the way they are, how our limbs are coordinated, what are the purpose of reflexes and how do they work, and how do we learn and refine complex motions. Unlike the defining problems of many other scientific disciplines, the main problems in robotics are far easier to describe to the layman.
In contrast to the lofty goals set by robotics researchers, the aims of this textbook are much more modest. Our focus will be on the analysis, planning and control of robotic mechanisms, the most popular physical manifestations of intelligent machines. Basically, a mechanism is constructed by connecting rigid bodies (called links) together with joints, so that relative motion between adjacent links becomes possible. In practice the rigid bodies may actually be elastic to some degree, and the joints may be affected by factors such as elasticity, backlash, friction, and hysteresis; throughout the book we shall for the most part consider only idealized robotic mechanisms, and not worry about these effects.
1
2
Mechanisms can be constructed in a serial fashion, like the familiar open chain industrial manipulator shown in Figure 1.1-(a). Mechanisms can also have closed loops, such as the parallel mechanism shown in Figure 1.1-(b).
In the case of an open chain all of its joints are actuated by motors, while for mechanisms with closed loops only a subset of the joints may be actuated.
Wheeled vehicles, often with one or more arms mounted at its base, also constitute another important class of robotic mechanisms that we consider in this book.
We now provide a preview of each of the chapters, which taken together
Preview
Robotics is a relatively young subject that has set itself the rather ambitious– some would say impossible–goal of trying to create intelligent, physical machines that think and behave like humans. This attempt to create intelligent machines naturally leads us to first examine ourselves, to ask, for example, why our bodies are designed the way they are, how our limbs are coordinated, what are the purpose of reflexes and how do they work, and how do we learn and refine complex motions. Unlike the defining problems of many other scientific disciplines, the main problems in robotics are far easier to describe to the layman.
In contrast to the lofty goals set by robotics researchers, the aims of this textbook are much more modest. Our focus will be on the analysis, planning and control of robotic mechanisms, the most popular physical manifestations of intelligent machines. Basically, a mechanism is constructed by connecting rigid bodies (called links) together with joints, so that relative motion between adjacent links becomes possible. In practice the rigid bodies may actually be elastic to some degree, and the joints may be affected by factors such as elasticity, backlash, friction, and hysteresis; throughout the book we shall for the most part consider only idealized robotic mechanisms, and not worry about these effects.
1
2
Mechanisms can be constructed in a serial fashion, like the familiar open chain industrial manipulator shown in Figure 1.1-(a). Mechanisms can also have closed loops, such as the parallel mechanism shown in Figure 1.1-(b).
In the case of an open chain all of its joints are actuated by motors, while for mechanisms with closed loops only a subset of the joints may be actuated.
Wheeled vehicles, often with one or more arms mounted at its base, also constitute another important class of robotic mechanisms that we consider in this book.
We now provide a preview of each of the chapters, which taken together