‘Soccerbot’ learns how to fall gracefully during matchesMay 21st, 2009 - 4:11 pm ICT by ANI
London, May 21 (ANI): Scientists have made a robot learn how to fall gracefully during soccer matches, reducing damage to themselves and their environment.
According to a report in New Scientist, to find out the optimum ways for a robot to fall, Javier Ruiz-del-Solar of the University of Chile in Santiago and his team used a computer simulation based on a humanoid robot called Nao, the player used by all teams competing in the RoboCup’s Standard Platform League.
Nao has 22 simple joints, each with a single degree of freedom, and is typical of the bipedal soccer robots being built today.
Ruiz-del-Solar and colleagues put their simulated soccerbot through a series of different fall sequences. The simulation computes the stresses on each joint, which can then be plugged into the team’s equations to work out the total damage factor.
They found that one of the main ways to minimise damage is for the robot to fold its legs underneath it. Among other things, that means the robot is much less likely to hit its head on the ground.
Another good strategy is to use a fall sequence consisting of several movements, so the falling body has several points of contact with the ground, spreading the energy of the impact over a large number of joints, rather than taking it all in one disastrous crunch.
One of the main ways to minimize damage is for the robot to fold its legs underneath it.
The Santiago team tested their method for real using their UCH H1 robot, which they built to compete in the RoboCup’s Humanoid League.
It is similar to Nao, but has a stronger frame and joints.
Using a high-speed camera, they recorded the speed and acceleration of the robot’s joints as it fell, and used that to calculate the forces and torques on each joint.
The tests confirm that UCH H1 suffers less damage when it bends its legs to keep its centre of mass low as it falls.
Ruiz-del-Solar estimates that a well-equipped soccerbot would need about five different fall sequences stored in its memory, to be triggered when the robot is fouled or needs to dive to save a shot on goal, for example.
The true test of the new work will come at this year’s RoboCup, to be held in Graz, Austria, in June and July, where the Santiago team are planning to try out their robot, programmed with safe fall sequences, on the soccer pitch. (ANI)
Tags: acceleration, centre of mass, computer simulation, crunch, degree of freedom, high speed camera, humanoid robot, javier ruiz, joints, legs, new scientist, robocup, santiago, sequences, several points, soccer robots, soccerbot, stresses, torques, university of chile