Gecko toes can adhere strongly to nearly any surface and yet release with minimal effort. Stanford University engineers are developing controllable, reusable adhesive materials that - like the gecko toes that inspire the work - can form a strong bond with smooth surfaces but also release with minimal effort. The team has developed a device that shares large loads very evenly across every patch of the adhesive, and it can create sufficient adhesion to allow a person to climb a glass wall. The current version of the device can support about 200 pounds. Each handheld gecko pad is covered with 24 adhesive tiles, and each of these is covered with sawtooth-shape polymer structures each 100 micrometers long (about the width of a human hair). The pads are connected to special degressive springs, which become less stiff the further they are stretched. This characteristic means that when the springs are pulled upon, they apply an identical force to each adhesive tile and cause the sawtooth-like structures to flatten. Manufacturing robots that lift large glass panels or LCD displays are a potential application, and the team is working with NASA's Jet Propulsion Laboratory to apply the devices to the robotic arms of spacecraft.