In the development of ASIMO, we realized functions that enabled ASIMO to 1) move around in the same space as people, such as walking among people and not falling down even when bumping into a person, 2) use its hands to perform tasks and 3) interact with people, such as understanding what people are saying and controlling its movements based on the intention of the people around it.
In addition to the hardware (multi-fingered hand), Honda Avatar Robot will require the development of various technologies including software technolgoies. For example, software that enables precise conctol as well as AI will be necessary to operate the robotic hand at the will of the operator. In this respect, Honda has been continuously amassing robotic technologies since the start of ASIMO development, and has specialists in various fields such as mechanical mechanisms design, control and AI. In addition, being a manufacturing company, Honda has highly capable prototyping teams, and the speed at which ideas are put into tangible form has been one of the major strengths of Honda.

Human hands feature both the delicate touch to pinch a small item and the strength to grasp an item firmly. On the other hand, currently available multi-fingered robotic hands, including the hands of ASIMO, are not as capable in this respect as human hands.
Honda addressed this challenge and achieved delicateness and strength similar to those of human hands by devising and precisely controlling the drive system of the mechanical mechanism. Our multi-fingered robotic hand can now perform a wider range of daily tasks, such as picking up a coin with dexterity, opening a can using a pull tab and opening a cap of a PET bottle.

ASIMO's hands were driven by a hydraulic actuator built into the torso, whereas the Honda Avatar Robot adopted a wire (cable)-driven mechanism in order to generate strong force while concentrating the components in the forearm rather than the torso.
The mechanism of a movable pulley, which is used for construction cranes and other equipment, was applied and built into each finger as a three-dimensional mechanism. As a result, fingertip force has been dramatically increased to more than five times that of ASIMO, while the components are built compactly into the forearm of the robot.

Compared to a direct drive system, where the motor drives the equipment directly via gears, precise control is more difficult to achieve with a wire-driven system due to the elongation of the wire. To address this issue, the effect of elasticity and friction is corrected by using tension sensors that measure wire tension and information such as finger bending angles. This enables accurate control of our multi-fingered hand. In addition, compact design also was pursued for the circuit system by dividing the circuit board into separate boards for each function.

The motors that drive the fingers of the robotic hand also play an important role in achieving both strength and delicateness. For example, to open the lid of a glass jar, the fingers must continue to hold on to the lid while applying strong force. So, we developed a motor that can continuously generate strong force suitable for such use. In the development of ASIMO, we conducted research on motors with high power density to weight ratio. We utilized knowledge obtained through such research to realize a compact yet high-power motor for our robotic hand. Eleven motors are built into the forearm to move four fingers with a total of 16 joints connected via wires, covering most of the hand shapes people use in their daily lives. As a result, our robotic hand is capable of performing a variety of tasks.

■All measurements included in this story were measured internally by Honda.

ASIMO achieved autonomous behavior by recognizing the movement of people around it based on information from multiple sensors and deciding its next action on its own without human intervention. With the Honda Avatar Robot, the human (operator) is responsible for recognizing the situation and deciding the robot's actions, while the AI supports operation by estimating the operator's intentions and applying corrective control to the multi-fingered hand in accordance with those intentions. Based on ASIMO's autonomous technology, we have been increasing the precision of such AI-based support by incorporating the latest AI technologies.

AI estimates the intensions of the operator based on multidimensional information obtained from various sensors installed to the avatar robot as well as to goggles and gloves worn by the operator. Based on the estimation of the operator’s intentions, necessary corrections will be made to the position of the finger/hand in relation to the object and the balance of forces to achieve smooth grasping.

＜Steps in estimating the operator’s intentions and making corrections to the movement of the robotic hand＞

• Plan:Using the technology to understand the intentions of people, the AI estimates which object the operator intends to grasp with which shape of the hand, based on the movement of the eyes and hands of the operator.
• Do:To address the issue of difficulty in achieving an accurate sense of distance to the object, position correction technology using 3D measurement is applied to adjust the position and angle of the multi-fingered hand to match the operator's sense of distance.
• Check:Proper grasp is checked by estimating the state of contact based on information from the 6-axis force sensor on the fingertips and the contact sensor on the surface of the hand, as well as information from the cameras.
• Adjust:Balance of the force applied to the object is corrected as needed. The feedback will be provided to the operator through vibration of the gloves.