The Laboratory of Intelligent Systems in Switzerland recently revealed the first robot prototype to come out of its project aimed at designing robots for applications that involve traversing complex terrains, such as semi-collapsed buildings, deep caverns, or forests with a lot of vegetation. Named DALER (Deployable Air Land Exploration Robot) after lead researcher, Ludovic Daler, the robotic platform is uniquely capable of both flight and ground locomotion.
What?s novel about the DALER platform is that it uses one set of limbs for both modes of transportation. To accomplish this, researchers applied ?adaptive morphology? to their robot design. The robot?s wings–termed ?whegs?–transform into walking legs after landing.
The robot was designed for flight, says Daler, and ?the main design challenge was to integrate the ground locomotion capability on the robot without reducing its flight performance.?
Not having to add an additional structure for a different mode of locomotion curbs the robot?s weight, therefore sustaining its flight capability.
This dual use of a single structure is unique for a robot. Most robots are only capable of one mode of locomotion. Those that are capable of two have a separate structure for each mode. Daler says ?the main disadvantage of multi-modal robots… is that they cannot have an optimal performance in each mode.?
Using its whegs, the DALER robot can fly at a speed of 14 m/s, and is capable of flying in winds of up to 12 m/s. But on the ground, the robot moves at a speed of 0.2 m/s and can rotate on the spot at 25°/s.
?Ground robots that use whegs to move in rough terrains usually have whegs with three or four spokes, whereas the DALER has whegs with two spokes,? says Daler. ?However, the geometrical parameters of the robot (the swept angle, the tapper ratio, and the length of the limbs) are designed to maximize the ground speed.? And the robot can still ?[walk] with different gaits, move on different surfaces, overcome high obstacles, and… navigate in rough terrains.?
Although the robot does face some disadvantages while walking, ?for the types of applications that we are targeting, most of the distances will be covered in forward flight,? which the robot is good at, says Daler. The main purpose of the robot will be search-and-rescue missions in rough terrain.
After covering most of the distance by flying, the robot will land and take less than a second to unlock its wings, making it capable of walking across the terrain in order to perform a careful search. The fact that the DALER robot can walk is a huge advantage in this circumstance, as merely hovering or flying low to the ground would not be as effective. But switching back to flight mode isn?t simple for the robot yet.
?From walking to flying it?s more complicated; this version of the DALER robot has to be launched by someone. However, the next version of the robot will have Vertical Take Off and Landing (VTOL) capability; which would make the robot fully autonomous,? Daler says.
As the robot was designed for these search-and-rescue missions, when it reaches production, it will be sold with specific software for that application. However Daler believes that the robot can be used in a myriad of ways.
?[It] could be used as a delivery system; it could land in your garden, drop a small package next to your door, and go back. Or it could also be sold as a remote controlled toy. I am convinced that we can find plenty other applications that we have not thought of yet.?