Safety mechanism for robotic bone cutting

Methods and systems for providing a safety mechanism for a robotically controlled surgical tool. Embodiments of these methods use sensors to detect parameters that vary with tissue traversed by a surgical tool. A sensor detects a signal generated by interaction of the surgical tool with the tissue and provides the information to the robotic controller. For example, during drilling, a sensor may measure power, vibration, sound frequency, mechanical load, electrical impedance, and distance traversed from preoperative measurements of a three-dimensional image set for a planned tool trajectory. By comparing the detected output to an output expected for the tool position based on the planned trajectory, the identified output difference will indicate that the tool has turned from the planned trajectory. The robot controller may, in turn, vary the tool trajectory, vary the speed of the tool, or interrupt power supply to the tool, thereby preventing damage to the underlying tissue. 用于为机器人控制的手术工具提供安全机构的方法和系统。这些方法的实施方案