Untethered Small-scale Robots for Biomedical Applications introduces the principle, design, fabrication and application of small-scale robots for biomedical applications. Robots in the scale of nanometer, micrometer and millimeter are described in detail, along with their impact on the field of biomedical engineering. The selected examples of robots across different scales are of the most essential and innovative designs in a small-scale robot with various application settings for biomechanics characterization, drug delivery and surgical procedure. The representative robots represented operate robustly and safely in complex physiological environments where they have a transformative impact in bioengineering and healthcare. This book will lead the audience to the field of small-scale robots through the description of the physics in the small scale, design and fabrication of small-scale robots, and how these robots may impact the future of biomedical studies and minimally-invasive surgical procedures.