Paul Bucci and colleagues from University of British Colombia report this month on Cuddlebots, “simple 1-DOF robots” that “can express affect”  As Evan Ackerman says, “build your own tribble!” (Why hasn’t there been a zillion Tribble analogs on the market???)
This caught my eye just because they are cute. Then I looked at the paper presented this month at CHI. Whoa! There’s a lot of interesting stuff here.
First of all, this is a minimalist, “how low can we go” challenge. Many social robots have focused on adding many, many degrees of freedom, for example, to simulate human facial expressions as faithfully as possible. This project goes the other way, trying to create social bonds with only one DOF.
“This seems plausible: humans have a powerful ability to anthropomorphize, easily constructing narratives and ascribing complex emotions to non-human entities.” (p. 3681)
In this case, the robot has programmable “breathing” motions (highly salient in emotional relationships among humans and other species). The challenge is, of course, that emotion is a multidimensional phenomenon, so how can different emotions be expressed with just breathing? And, assuming they can be created, will these patterns be “read” correctly by a human?
This is a great piece of work. They developed theoretical understanding of “relationships between robot behaviour control parameters, and robot-expressed emotion”, which makes possible a DIY “kit” for creating the robots – a theory of Tribbleology, and a factory for fabbing Tribbles!
I mark their grade card with the comment, “Shows mastery of subject”.
As already noted, the design is “naturalistic”, but not patterned after any specific animal. That said, the results are, of course, Tribbleoids, a fictional life form (with notorious psychological attraction).
The paper discusses their design methods and design patterns. They make it all sound so simple, “We iterated on mechanical form until satisfied with the prototypes’ tactility and expressive possibilities of movement.” This statement understates the immense skill of the designers to be able to quickly “iterate” these physical designs.
The team fiddled with design tools that were not originally intended for programming robots. The goal was to be able to generate patterns of “breathing”, basically sine waves, that could drive the robots. This isn’t the kind of motion needed for most robots, but it is what haptics and vocal mapping tools do.
Several studies were done to investigate the expressiveness of the robots, and how people perceived them. The results are complicated, and did not yield any completely clear cut design principles. This isn’t terribly surprising, considering the limited repertoire of the robots. Clearly, the ability to iterate is the key to creating satisfying robots. I don’t think there is going to be a general theory of emotion.
I have to say that the authors are extremely hung up on trying to represent human emotions in these simple robots. I guess that might be useful, but I’m not interested in that per se. I just want to create attractive robots that people like.
One of the interesting things to think about is the psychological process that assigns emotion to these inanimate objects at all. As they say, humans anthropomorphize, and create their own implicit story. It’s no wonder that limited and ambiguous behavior of the robots isn’t clearly read by the humans: they each have their own imaginary story, and there are lots of other factors.
For example, they noted that variables other than the mechanics and motion While people recognized the same general emotions, “we were much more inclined to baby a small FlexiBit over the larger one.” That is, the size of the robot elicited different behaviors from the humans, even with the same design and behavior from the robot.
The researchers are tempted to add more DOF, or perhaps “layer” several 1-DOF systems. This might be an interesting experiment to do, and it might lead to some kind of additive “behavior blocks”. Who knows
Also, if you are adding one more “DOF”, I would suggest adding simple vocalizations, purring and squealing. This is not an original, this is what was done in “The Trouble With Tribbles” (1967) .
- Paul Bucci, Xi Laura Cang, Anasazi Valair, David Marino, Lucia Tseng, Merel Jung, Jussi Rantala, Oliver S. Schneider, and Karon E. MacLean, Sketching CuddleBits: Coupled Prototyping of Body and Behaviour for an Affective Robot Pet, in Proceedings of the 2017 CHI Conference on Human Factors in Computing Systems. 2017, ACM: Denver, Colorado, USA. p. 3681-3692.
- Joseph Pevney, The Trouble With Tribbles, in Star Trek. 1967.