The RIKEN Guardian Robot Project showcase their newest project to create an expressive android that can convey the six basic emotions through facial expressions.
Researchers from the RIKEN Guardian Robot Project in Japan have made an expressive android child named Nikola that successfully conveys six basic emotions.
A new study, published in Frontiers in Psychology, tested how well people could identify six different facial expressions—happiness, sadness, fear, anger, surprise, and disgust—which were generated by moving ‘muscles’ in Nikola the android’s face. This is the first time that the quality of android-expressed emotion has been tested and verified for these six emotions.
Nikola the expressive android child
Rosie the robot maid was considered science fiction when she debuted on the Jetson’s cartoon over 50 years ago. Although the reality of the helpful robot is currently more science and less fiction, many challenges remain that need to be met, including the ability to detect and express emotions. The recent study led by Wataru Sato from the RIKEN Guardian Robot Project focused on building a humanoid robot, or android, that can use its face to express a variety of emotions. The result is Nikola, an android head that looks like a hairless boy.
Inside Nikola’s face are 29 pneumatic actuators that control the movements of artificial muscles. Another 6 actuators control the head and eyeball movements. Pneumatic actuators are controlled by air pressure, making the movements silent and smooth. The team placed the actuators based on the Facial Action Coding System (FACS), which has been used extensively to study facial expressions. Past research has identified numerous facial action units—such as ‘cheek raiser’ and ‘lip pucker’—that comprise typical emotions such as happiness or disgust, and the researchers incorporated these action units in Nikola’s design.
The study of emotions in AI
Typically, studies of emotions, especially how people react to emotions in AI, can be challenging. It is difficult to conduct a properly controlled experiment with live people interacting, although, looking at photos or videos of people is less natural, and reactions are not the same.
“The hope is that with androids like Nikola, we can have our cake and eat it too,” explained Sato. “We can control every aspect of Nikola’s behaviour, and at the same time study live interactions.” The first step was to see if Nikola’s facial expressions were understandable.
A person certified in FACS scoring was able to identify each facial action unit, indicating that Nikola’s facial movements accurately resemble those of a real human. A second test showed that everyday people could recognise the six prototypical emotions—happiness, sadness, fear, anger, surprise, and disgust—in Nikola’s face, albeit to varying accuracies. This is because Nikola’s silicone skin is less elastic than real human skin and cannot form wrinkles very well. Thus, emotions like disgust were harder to identify because the action unit for nose wrinkling could not be included.
Guardian robot project results
“In the short term, androids such as Nikola can be important research tools for social psychology or even social neuroscience,” added Sato. “Compared with human confederates, androids are good at controlling behaviours and can facilitate a rigorous and empirical investigation of human social interactions.”
As an example, the researchers asked people to rate how natural Nikola’s emotions are as the speed of his facial movements were systematically controlled. They researchers discovered that the most natural speed was slower for some emotions, like sadness, than it was for others, such as surprise.
While Nikola is still without a body, the ultimate objective of the Guardian Robot Project is to build an android that can assist people, particularly those which physical needs who might live alone. “Androids that can emotionally communicate with us will be useful in a wide range of real-life situations, such as caring for older people, and can promote human wellbeing,” concluded Sato.