This book is written as an initial course in robotics. It is ideal for study of unmanned aerial or underwater vehicles, a topic on which few books exist. It presents the fundamentals of robotics, from an aerospace perspective, by considering only the field of robot mechanisms. For an aerospace engineer, three dimensional and parallel mechanisms - flight simulation, unmanned aerial vehicles, and space robotics - take on an added significance. Biomimetic robot mechanisms are fundamental to manipulators, walking, mobile, and flying robots. As a distinguishing feature, this book gives a unified and integrated treatment of biomimetic robot mechanisms. It is ideal preparation for the next robotics module: practical robot control design. While the book focuses on principles, computational procedures are also given due importance. Students are encouraged to use computational tools to solve the examples in the exercises. The author has also included some additional topics beyond his course coverage for the enthusiastic reader to explore.