On December 15th, 2004, Honda unveiled a major revision to Asimo. Asimo(2004) can walk at up to 2.5 km/h, and can run at 3 km/h. In order to run, Asimo(2004) lifts both feet off of the ground for 0.05 seconds. Asimo(2004) is 10 cm taller at 130 cm and weighs 54 kg. The battery life has doubled to 1 hour due to a 51.8 V Lithium Ion battery pack. Asimo(2004) also features 34 DoF: a hip rotational joint which helps cancel out reaction force from faster walking, two wrist joints per arm, thumb joint (all 5 fingers were driven by one motor before), and an additional neck joint. In order to achieve that 3 km/h speed, Asimo(2004) has new high speed motor drive units, light-weight legs, and new control theory to prevent spinning and slipping. It’s also important to note that Asimo(2004) has a completely redesigned exterior, featuring a smaller “backpack” and lights on either side of the head.
As Asimo(2004) grew 10 cm to accommodate the added hardware, the design team realized that they needed to increase the length of the legs to keep the proportions looking correct. More lights were added to the chest and the head to communicate robot status to humans. The backpack was no longer necessary due to a more compact battery. Special attention was paid to the new hip rotational joint which could cause the torso to look separate from the lower hip. Flexible material was added to allow for more range of motion in the arms.
On December 13th, 2005, Honda revised Asimo to increase its walking speed to 2.7 km/h and its running speed to 6 km/h. Asimo(2005) has an improved ability to recognize its environment due to visual sensors, floor surface sensor, ultrasonic sensor, and ability to recognize an IC communication card that people can wear as a badge. Asimo(2005) can also hold a person’s hand, push a cart, and move objects on a tray using force sensors on each wrist. Honda also notes that Asimo(2005) can walk at 1.6 km/h while carrying an object weighing 1 kg.
