Standing four feet tall and weighing 95 pounds, Honda's Asimo walked onto the stage like a small child, with a fast, smooth gait that amazed the human observers. Not to be outdone, one of Sony's Aibo robots showed its smarts by finding, and then netting, a soccer ball of a certain color.

"The early decades of the 21st century will be the era of the robot," declared Toshi T. Doi, president of Sony's Digital Creatures Laboratory. "We expect that the robot industry will eventually grow larger than the PC industry."

Sony's soccer-playing Aibo 'bot has a camera, mikes, and smarts.

The brains behind Honda's Asimo is a PowerPC processor. The 'bot incorporates a total of 26 joints: two in the head, five in each arm, one per hand and six in each leg. At the demonstration here, Asimo was put through its paces from a workstation and also by a remote controller.

Honda researchers have developed several generations of humanoid robots over the past 14 years. Asimo — the name stands for "Advanced Step in Innovative Mobility" — is based on technologies incorporated in Honda's 1997 model, the P3 prototype, which was 64 inches tall and weighed a hefty 286 pounds.

Honda engineers said they decided to downsize Asimo to 48 inches, a height perceived as "a people-friendly size." (Indeed, it might be intimidating to have a robot in the house as large as oneself.) At 4 feet, Asimo is able to reach switches and doorknobs, and can perform tasks at tables and benches.

Honda's goal is to develop autonomous humanoid robots that will be useful in society, able to help people in daily life and take on dangerous work in places not fit for human beings. "Honda hopes to create a partner for people, a new kind of robot with a positive function in society," said Hiroyuki Yoshino, president and chief executive officer of Honda Motor Co. Ltd.

Earlier biped robots have walked slowly in order to keep their balance, but Asimo's maximum walking speed is one mile per hour — still slow compared with the average human. Asimo is able to change direction without stopping; the earlier P3 robot had to halt and stamp its feet before switching direction.

Honda sees its child-size Asimo as 'a partner to people,' around the house and on the job.

Honda engineers at the preview said they combined newly developed Predicted Movement Control technology, which forecasts the robot's next move and shifts the center of gravity accordingly, with existing walking-control know-how used in the P3.

Asimo has a six-axis sensor in each foot, and a gyroscope and deceleration sensor in its torso. Using these sensors, the 'bot can respond quickly, and the sensors help it walk with a natural and stable gait.

Entertainment goal

While Honda has a helpmate for humans in mind, Sony's goal is entertainment. At Robodex2000, Sony demonstrated Aibo, a humanoid robot that stands 20 inches high and weighs in at 11 pounds. Aibo also goes by the model name SDR-3X (SDR stands for Sony Dream Robot), and Sony's dream is to amuse customers and, it hopes, make a pile of money in the process.

Doi, a veteran Sony executive who has spearheaded earlier efforts in the computer field, said Sony made the SDR-3X "as small as possible. We developed this prototype for entertainment, and so it does not need to climb stairs. The smaller it is, the lower the cost becomes."

The SDR-3X robots did more than just walk around. Sony built six units and used four of them in a demonstration during which one robot walked, squatted, got up, balanced on one leg, was directed to search for a colored soccer ball and then kicked that ball into the goal. Three other robots showed up as a dancing team, waltzing around the stage and doing synchronized choreography.

To accomplish that feat, Sony engineers developed actuators that move the joints and real-time control software called Whole Body Coordinated Dynamic Control.

The SDR-3X walks at a maximum rate of 16.5 yards per minute, or roughly 1,000 yards an hour. It achieves a 5-inch stride by moving the upper half of the body to counteract the yaw-axis movement generated by the lower half, much as a human being walks. Aibo is able to climb 10 slopes, and uses information gathered from posture sensors in the torso area and touch sensors on the bottom of its feet to control its posture and keep from falling over. But even if the robot stumbles, it can usually stand up on its own, said a Sony engineer.

The SDR-3X has 24 joints: two for the head, two in the torso, four per arm and six per leg. The newly developed actuators that move the joints consist of a motor unit, a gear unit and a control ASIC. The small actuators generate considerable power partly because the motor, gear and ASIC are packaged as one device. To obtain high power in small actuators, Sony engineers opted to integrated these three basic components.

The most powerful actuator, used in the knee joints, generates a torque of 24 kg.-cm at 1 amp. Two other actuators were developed for other, less powerful joints.

The SDR-3X employs two 64-bit MIPS processors, one for information processing and the other for motion control. The robot has a variety of sensors, including a CCD camera, two microphones, and the posture sensors and touch sensors in its feet. The inputs gathered by the sensors go first to the information processor, then get passed to the motion processor, which synchronizes movements of the body joints.

Sony's newest robot has eyes, ears and a mouth. It recognizes about 20 words and answers in about 20 prerecorded words, and can distinguish color from visual data captured by the CCD camera. In the soccer-playing demo, the SDR-3X recognized an instruction to find a colored ball. It located the net, moved next to the ball, shot the ball and then recognized whether the ball landed in the net or missed.

The demonstration was programmed via Sony's Memory Stick flash cards. The SDR-3X also can be operated by remote control, using a wireless-LAN card in the robot's PC-card slot.

Child of Open-R

In June 1998, Sony proposed the Open-R architecture for entertainment robots, envisioning the robot as a game-playing platform. Built around Sony's proprietary Aperios real-time operating system, the Open-R architecture features hardware and software modules that handle components of the robot's functioning. Movement-control software and information-processing programs such as speech recognition and image recognition are subdivided into modules specific to each function. For small robots, hardware modules are connected by a 10-pin Open-R bus.

By combining hardware modules and software modules, new robots with new functions can be devised. "We developed Aibo as an application of Open-R," said Doi. "We envisioned that with a modular architecture we could develop a biped robot, and these robots are proof." Doi said that robot designers "usually develop a proprietary architecture first, then start working on robot development." But in his view, "that is a big waste."

Doi noted that the same basic technologies used in entertainment robots could be applied to working robots. "I don't think that we need to divide robots into ones for serious tasks and ones for entertainment, like Aibo," he said. "Eventually the distinction will disappear."