In 2014, we have a lot of robots. We have robots or drones that fly through the air, that walk on the ground, float on or dive under the water. We even have robots exploring the surface of Mars. What we do not have at this point is robots that can do more than one of these things. The specialized equipment that allows a robot to do one of these things generally does not allow it to have the specialized equipment to do a second of these things.

New research published in Bioinspiration and Biometrics has now challenged that norm. A team led by Ludovic Daler describes the Deployable Air-Land Exploration Robot (DALER), a robot that is modeled on the vampire bat and can use its wings for flight as well as walking. The DALER uses adaptive morphology to allow for wings that have a folding skeleton mechanism covered with a soft fabric that allows the limbs to be used as wings, or whets as the researchers refer to them.

The DALER is being designed as a joint project between LIS, EPFL and NCCR Robotics. It is intended, primarily, as a tool for search and rescue operations. The robot could, for example, conduct aerial surveillance of the site of a natural disaster and then land and explore individual buildings. It could also assist in a search for a downed plane and then, once it is located, export the fuselage or fly into a nuclear power plant and then explore pipes and passageways searching for the source of a problem.

Ordinarily, flying robots or drones cannot be used in tight spaces. Even if they have a means of moving on the ground, the necessary wingspan for flight prevents them from moving into narrow passages. The researchers observed the unique solution to this problem taken by Desmodus rotundus, the common vampire bat in an attempt to find a mechanical solution.

The DALER uses a foldable actuator to allow the wings to fold into a small space and then rotate around a hinge which attaches the whegs to the body. “D. rotundus doesn’t look very pretty when it walks, but it has certainly perfected the art of using all four limbs for two purposes,” according to a statement.

In designing the drone the team had to choose a primary method of locomotion, in this case flight, and then search for a means of allowing the robot to walk without adding extra weight which would interfere with its primary method of movement.

The team also had to solve the problem of maintaining an optimal center of mass for both walking and flying. In other words, they had to ensure that, after the DALER shifted from one mode to the next it had the proper balance for the next activity, walking or flying.

In tests the DALER can reach speeds of 20 meters or 65 feet per second in the air and 6 centimeters or 2.36 feet per second while walking.

A video demonstrating the DALER’s wing technology as well as other videos demonstrating the evolution of the idea can be found on Ludovic Daler’s YouTube channel.