Ensuring mobility of the elderly is an important task in our aging society. To this end, this paper presents an automatic speed controller for the SmartWalker – a high-tech extension of a regular walker. The walker locates its user by detecting the user’s legs using a laser range scanner. The controller then determines the optimal speed for the walker using the user’s location and other sensory data. We evaluated the walker and its speed controller with thirteen residents at three different retirement homes. Our analysis showed that the walker with the controller is slightly more comfortable and easier to maneuver than the walker without the controller and is more liked than traditional walkers. Categories and Subject Descriptors H.5.2 [Information Interfaces and Presentation]: User Interfaces—Input devices and strategies, Interaction styles; I.2.9 [Artificial Intelligence]: Robotics General Terms Experimentation, Human Factors Keywords Ambient assisted living, Robotics