What is a Capstan Drive? Cable, or Capstan, drives are special reducers which act similarly to spur gears but which implement cables and drums to transmit motion and increased torque for the desired application. Advantages of these systems include high stiffness, low backlash, and low inertia which are typically sought in legged robots or similar applications. However, they are subject to other disadvantages like size, limited rotation, and stretching of the cable (creep). To accommodate this and achieve stiff cables, they are often equipped with a tensioning system. Project Motivation and Goals To better understand the design considerations of the drive system and to gain hands-on experience with its design, this project was undertaken. Additionally, the project investigates its potential application to drive a robotic manipulator. 1. Design and build a functional Capstan reducer capable of transmitting some torque and rotation to the output drum 2. Exhibit a near 10:1 reduction 3. Implement the design in a 2-DOF symmetric 5-bar linkage