A capstan represented by a Belt Pulley block from the Simscape™ Driveline™ library. A 100-N tension applied to belt end A holds a variable load at end B in place, even as the load increases. When the load force increases past the friction limit, the belt slips. Increasing the friction by using a higher friction coefficient or wrap angle allows the pulley to hold an even greater load force. This example also shows how suddenly turning the capstan, starting at 5 seconds, causes momentary slip, which is quickly recovered.