Researchers Wietse van Dijk and Cor Meijneke from biomechanical engineering (3mE) have created robot boots, which provide an additional boost when the wearer steps down on the heel, making it easier to walk. The Achilles walking boot, as the invention has been named, contains a spring system and a small electro-motor. The device could be useful for people with muscle disease or for those in rehabilitation. The technique does not yet work perfectly. The movement still feels unnatural, causing users to adopt another walking posture – putting more weight on their toes – thereby failing to reduce the amount of energy used. By improving the mathematical models of human walking dynamics, the researchers hope that they will ultimately be able to improve their robot boots.