Thursday, August 31, 2017

Toward Ubiquitous Robotic Organisms

bbvaopenmind |  Nature has always found ways to exploit and adapt to differences in environmental conditions. Through evolutionary adaptation a myriad of organisms has developed that operate and thrive in diverse and often extreme conditions. For example, the tardigrade (Schokraie et al., 2012) is able to survive pressures greater than those found in the deepest oceans and in space, can withstand temperatures from 1K (-272 °C) to 420K (150 °C), and can go without food for thirty years. Organisms often operate in symbiosis with others. The average human, for example, has about 30 trillion cells, but contains about 40 trillion bacteria (Sender et al., 2016). They cover scales from the smallest free-living bacteria, pelagibacter ubique, at around 0.5µm long to the blue whale at around thirty meters long. That is a length range of 7 orders of magnitude and approximately 15 orders of magnitude in volume! What these astonishing facts show is that if nature can use the same biological building blocks (DNA, amino acids, etc.) for such an amazing range of organisms, we too can use our robotic building blocks to cover a much wider range of environments and applications than we currently do. In this way we may be able to match the ubiquity of natural organisms.

To achieve robotic ubiquity requires us not only to study and replicate the feats of nature but to go beyond them with faster (certainly faster than evolutionary timescales!) development and more general and adaptable technologies. Another way to think of future robots is as artificial organisms. Instead of a conventional robot which can be decomposed into mechanical, electrical, and computational domains, we can think of a robot in terms of its biological counterpart and having three core components: a body, a brain, and a stomach. In biological organisms, energy is converted in the stomach and distributed around the body to feed the muscles and the brain, which in turn controls the organisms. There is thus a functional equivalence between the robot organism and the natural organism: the brain is equivalent to the computer or control system; the body is equivalent to the mechanical structure of the robot; and the stomach is equivalent to the power source of the robot, be it battery, solar cell, or any other power source. The benefit of the artificial organism paradigm is that we are encouraged to exploit, and go beyond, all the characteristics of biological organisms. These embrace qualities largely unaddressed by current robotics research, including operation in varied and harsh conditions, benign environmental integration, reproduction, death, and decomposition. All of these are essential to the development of ubiquitous robotic organisms.

The realization of this goal is only achievable by concerted research in the areas of smart materials, synthetic biology, artificial intelligence, and adaptation. Here we will focus on the development of novel smart materials for robotics, but we will also see how materials development cannot occur in isolation of the other much-needed research areas.