Stepping up a gear

On an anonymous industrial estate just outside Brussels the world’s most sophisticated humanoid robot is being put through its paces. Climbing stairs, balancing on tilting surfaces, as well as meeting and greeting in the cutesy tones of a brattish American 12-year-old, Honda’s Asimo is a wonder of modern robotics innovation.

First introduced to the world in 2003, Asimo is the product of more than 20 years of research by Honda in a bid to develop a truly useful humanoid robot which can work alongside humans. Far removed from the early giant-sized disembodied legs that made their first faltering steps in Japan, Asimo has wowed people around the world on its frequent public appearances.

This autumn, the latest version — known as ‘New Asimo’ — is due to reach Europe. Launched early last year in Japan, the robot’s latest incarnation boasts a host of new features that bring it one step closer to full robotic autonomy.

It is in one of Asimo’s most noticeable upgrades that the philosophy of the Asimo project is perhaps most apparent. On the mobility side, the robot now has the ability to run at almost four mph (six kph) — twice the speed of the previous generation. According to Honda’s William de Braekeleer there was no real necessity to make Asimo run faster, but once the challenge had been set, Honda’s engineers were determined to find a way to make it happen, he said. It has been this setting of pure research challenges to be overcome which has driven Asimo’s development over the past two decades.

Running is defined as when both feet are off the ground simultaneously. While Asimo’s feet are both airborne for no longer than 0.08 seconds, Honda had to work on the robot’s proactive body control while in the air to increase its running speed.

Another improvement is Asimo’s ability to run in a circular pattern at five kph as well as being able to slalom in between objects. This was made possible by automatic adjustments inside the robot’s body to allow it to alter its centre of gravity as it turns. Honda was also forced to develop fully rotating hips — much like in humans — for the new Asimo to allow it to twist and keep its balance while running. These have added 10cm to its height, but the robot is still considered small enough to be eye-level with a seated human — a crucial consideration for Honda which was aware that humans find it disconcerting to interact with much larger robots.

According to de Braekeleer, it is challenges like this that show just how much humans take for granted in their mobility.

‘When you try to develop a humanoid robot you realise just how complicated the human body is,’ he said. ‘For Asimo, every single movement or balancing adjustment must be thought of in advance.’

The new robot is also far more aware if its surroundings. As well as cameras fitted around its waistband which allow it to line up with markers for when it climbs stairs, it now comes equipped with 360º ultrasonic sensors. These allow Asimo to build an image of its environment and — along with surface sensor lasers — mean it is far more able to map out the terrain ahead so it can alter its gait if necessary. ‘The beauty of this system is that it uses all of these sensors in the most effective way to help it react. That’s a big technology change,’ said de Braekeleer.

With the combination of eye cameras and new force sensors embedded in its wrists, Asimo can now perform basic tasks with a high degree of autonomy. For example, when pushing a trolley Asimo can gauge the pressure required to push it in the right direction and can adjust the force it is exerting appropriately. These sensors allow it to receive and deliver objects effectively, and be able to judge when the object has left its grasp by calculating the change in weight.

The force sensors also mean that Asimo can walk with a human by holding their hand and can constantly measure the pressure being applied to move in sync with a human partner.

One of the key differences in the new Asimo is its enhanced ability to interact with humans. It comes equipped with something known as a IC Tele-interaction Communication Card, a device that creates a link between the human carrying the card and the robot.

This means that Asimo is aware of the existence and position of the human or object carrying the card anywhere within a 360º range. ‘Once you take the card Asimo knows that this is the person who needs to be guided and their name,’ said de Braekeleer. ‘Because it’s aware of where the person is, if it moves ahead of you and you stop to look at something it will stop and wait and even tell you to keep up — it is far more advanced.’

All of these upgrades mean that Honda has greatly improved Asimo’s mobility, but while it is likely there will be future improvements to come in this area, the focus is now moving on elsewhere, according to Honda.

‘Our first targets for robotic mobility have been reached,’ said de Braekeleer. ‘It will never stop improving entirely, but we have reached a level and now it is the robot’s intelligence that is the most important.’

Asimo’s artificial intelligence is already quite advanced. Its software allows it to recognise humans by measuring the distance between their pupils and matching it to a database in which it can store up to about 100 different individuals. This function allows it to greet recognised humans on sight.

It also has fairly advanced gesture recognition software so it can recognise a number of different movements and can even be ‘sent’ to a corner by following the trajectory of an outstretched arm.

However, it is video footage at Honda’s Tokyo laboratory that provides a clue to the new direction Asimo is going to take. The footage shows the robot being presented with a bottle. Automatically, it reaches out its hand to grasp the bottle, its eye cameras detecting the correct orientation to grip it, its head tilting and manoeuvring to work out the angles.

The researcher then begins to move the bottle across Asimo’s field of vision, always keeping it just out of reach. Asimo quickly readjusts and moves its hand, in sync with the bottle, ready to take it. Suddenly, the robot lowers its left arm and raises the right. It had deduced that it was more efficient to use the other arm to take the object. According to de Braekeleer, this is an incredible step forward in Asimo’s artificial intelligence.

‘They want Asimo’s behaviour to adapt according to its environment,’ he said. ‘Concentrating on this kind of intelligence is the main focus now.’

With new Asimo’s European premiere, expect another round of crowd-pleasing presentations. But the Asimo project has always had a far more practical aim. As well as developing the first real robot that humans can welcome into their lives, the technology developed for the robot often finds its way into other areas of Honda’s output, a fact that de Braekeleer admits is almost as important as the robot itself.

Technologies such as posture control, image and voice recognition and crash avoidance systems are already being applied in Honda’s automotive research. As de Braekeleer said: ‘The future of intelligent vehicles may well start with Asimo.’