Keisuke Suga

Fast running experiments involving a humanoid robot

The present paper describes an implementation of fast running motions involving a humanoid robot. Two important technologies are described: a motion generation and a balance control. The motion generation is a unified way to design both walking and running and can generate the trajectory with the vertical conditions of the Center Of Mass (COM) in short calculation time. The balance control enables a robot to maintain balance by changing the positions of the contact foot dynamically when the robot is disturbed. This control consists of 1) compliance control without force sensors, in which the joints are made compliant by feed-forward torques and adjustment of gains of position control, and 2) feedback control, which uses the measured orientation of the robots torso used in the motion generation as an initial condition to decide the foot positions. Finally, a human-sized humanoid robot that can run forward at 7.0 [km/h] is presented.

Biped navigation in rough environments using on-board sensing

We present an approach to navigating a biped robot safely and efficiently through a complicated environment of previously unknown obstacles and terrain using only on-board sensing and odometry. Sensing of the environment is performed by a pivoting laser scanner, which continues to update the terrain representation as the robot walks. Safe stepping motions are planned from this data to follow the users command, given in the form of an end goal, a rough path, or a joystick input. Results are demonstrated on a prototype robot in several environments.

Realization of biped walking on uneven terrain by new foot mechanism capable of detecting ground surface

We have developed a new biped foot mechanism capable of detecting ground surface to realize stable walking on uneven terrain. The size of the foot mechanism is 160 mm × 277 mm and its weight is 1.5 kg. The foot system consists of four spikes each of which has an optical sensor to detect ground height. The foot makes a support polygon on uneven terrain by using three or four spikes. We have conducted several experiments on the outdoor ground surface that has a slope of 7.0 degrees and a maximum height of 15 mm bumps, and the effectiveness of the foot mechanism is confirmed.

Motion having a Flight Phase: Experiments Involving a One-legged Robot

In the present paper, we introduce a new method by which to generate motions having flight phases such as jumping or running. Such motions are expected to expand the speed and stability of legged robots. Motions with flight phases are examined with respect to jumping, stability and implementation. A novel method of determining the center of mass (COM) and foot locations is proposed that is independent of the target robot actuators or assignments of joints. Moreover, the proposed method allows an on-line system to be built easily and is useful for actual robots. A one-legged jumping robot having a toe joint is built in order to demonstrate the feasibility of this method. Using the toe joint of the robot, the proposed method can reduce the angular velocities of the joints remarkably. Experiments are conducted to investigate the control of the direction, velocity and turning of the robot

One-legged Jumping Robot

This video demonstrates a one-legged robot which moves by repeating jumps. The motions having flight phases such as jumping or running are expected to expand the speed and stability of legged robots. A novel method of determining the Center of Mass (COM) and foot locations is proposed that is independent of the target robot actuators or assignments of joints, and suitable for building an on-line control system. Using the toe joint of the robot, the proposed method can reduce the angular velocities of the joints remarkably. This video includes an experiment to control of the direction, velocity and turning of the robot. In addition, the maximum vertical jumps which have 180[ms] flight phases are shown.