An American team was able to optimize the process an amazing six-legged walking robot. Result: The machine is fifteen times faster than the rovers to the Martian Nasa.
On 26 April 2005, the Mars rover Opportunity, which then rolls over a year on the planet red, bogged down in an area of very fine sand. The engineers of JPL will need to replenish on Earth the ground that has trapped the rover and the development of slow and complicated maneuvers to clear the small craft lost on Mars. A year later, in June 2006, Opportunity bogged down again in front of the Victoria crater.
Five years after its landing, the rover has traveled 13.62 km. His brother, twin, Spirit, who arrived some twenty days before him, totaling 7.53 km. The feat is remarkable as it is the longest exploration carried out on a planet (Opportunity has done better than Lunakhod 1, the robot made by the USSR in 1970, which ran 10.54 km on the Moon) .
After immobile Phoenix, NASA is ready the next rover, Mars Science Laboratory, which will fly to Mars in 2011 (not 2009 as originally planned). As Spirit and Opportunity, the device will move by rolling.
For future missions to Mars or elsewhere, it might well be that Explorer is a craft legs. The assumption, at least, is seriously studied. Department of Physics at the Georgia Institute of Technology (Atlanta), Daniel Goldman directs a laboratory called Complex Rheology and Biomechanics Lab, or, more graphically, the Crab Lab.
Walk without getting bogged down? A question of know-how
With his team is studying how animals such as lizards, cockroaches, turtles or crabs, are doing to move, sometimes rapidly, over all kinds of soils, cluttered with the most diverse. If man is proud of having invented the wheel, nature has never served, but uses the legs with formidable efficiency. Not a lizard would have left as sand encroachment Opportunity.
The walking robots have long proved their effectiveness. An American company, Boston Dynamics, has produced a range of small six-legged robots, hexapod therefore, RHex, which have impressive capabilities for obstacle, as shown in the video we present here. Their mechanism is quite simple since the legs, curves, turning like a needle shows. It is therefore not of articulation. The team of Daniel Goldman used a cousin Sandbot, a hexapod robot by 2.3 kg made by Sandbox Innovations, a spin of the University of Pennsylvania.
Researchers have modified the program to inculcate the way of walking adopted by lizards and cockroaches on the very fine sand. On such a substrate granular, the movements and the weight of a leg (or a wheel) disrupt the assembly of grains of sand, which crumble and cause the deadlock. The phenomenon occurs because the movement is fast. To cope, we must move more slowly. This is what the Mars rovers. But not used legged animals of the desert. The researchers noted that in a very loose soil, slowing down their legs when they touch the sand while their movement in the air is faster. In dealing with cockroaches, the team was also able to observe a hexapod at work and see that the right strategy is to move three legs at once. To make progress, the Sandbot had three legs simultaneously in the sand and then slows the movement and it accelerates to the other three, in the process of turning in the air.
With these tricks animals, Sandbot darkens rescheduled to 30 centimeters per second (about 1 km / h) on very loose soil, fifteen times the speed of the Mars rovers at NASA. With a clearing obstacles more effectively, it has something of interest to the U.S. space agency. This research has also attracted the attention of the U.S. Army.Will we ever drones legged waging war on Earth or explore other planets?