Asimo is a humanoid robot who has overcome the challanges and obstacles of walking technology to tour the world and demonstrate hhis amazing feats of human activity.
ASIMO, a humanoid robot, was created by the Honda Motor Company, a producer of cars, motorcycles and power products, as a new challenge in mobility --- the development of a two-legged humanoid robot that can walk. Standing at 4 feet 3 inches and weighing 119 pounds, the robot resembles a small astronaut wearing a backpack and can walk or run on two feet at speeds up to 3.7 mph.
The Concepts Behind Asimo
Back in 1986, the main concept behind Honda's robot was to create a robot with more viable mobility that would allows robots to help and live in harmony with people. Research began by envisioning the ideal robot form for use in human society. The idea was that the robot would need to be able to maneuver between objects in a room and be able to go up and down stairs. For this reason it had to have two legs, just like a person. In addition, if two-legged walking technology could be established, the robot would need to be able to walk on uneven ground and be able to function in a wide range of environments. Although considered extremely difficult at the time, Honda set itself this ambitious goal and developed revolutionary new technology to create a two-legged walking robot.
The Challenge of Two-Legged Walking Technology
To achieve stable walking, the following issues needed to be addressed:
- Not falling down even when the floor is uneven.
- Not falling down even when pushed.
- Being able to walk stable on stairs or slopes.
This is achieved by three posture controls that achieve stable walking. The first is “Floor Reaction Control” which absorbs irregularities in the floor and controls the placement of the soles of the feet when falling is imminent. For example, if the tip of the robot's toe steps on a rock, the actual center of ground reaction shifts to the tip of the toe. The floor reaction control then causes the toe to rise slightly, returning the center of ground reaction to the target ZMP, or Zero Moment Point when the total inertia force is zero.
The target ZMP control, the next posture control, operates to prevent the robot from falling if the robot leans too far over. The target ZMP control maintains the robot's stability. For example, if the robot starts to fall forward, its walking speed is accelerated forward from the ideal walking pattern. As a result, the target ZMP is shifted rearward from the actual floor reaction action point and a rearward falling force is created which corrects the robot's position.
The final posture control, the “Foot Planting Location Control”, uses side steps to adjust for irregularities in the upper torso caused by target ZMP control. This stepping placement control idealizes the stride to ensure the ideal relationship between torso speed and length of stride is maintained.
Asimo Today
As of 2007, there are 46 ASIMO units in existence. Each one costs less than $1 million to manufacture, and some units are available to be hired out for $166,000 per year.
