biomimetic
Biomimetics or biomimicry is the emulation of the models, systems, and elements of nature for the purpose of solving complex human problems. The terms "biomimetics" and "biomimicry" are derived from grc, βίος (''bios''), life, and μίμησ ...
autonomous robot
An autonomous robot is a robot that acts without recourse to human control. The first autonomous robots environment were known as Elmer and Elsie, which were constructed in the late 1940s by W. Grey Walter. They were the first robots in history ...
s capable of building complex structures without a central controller. A prototype team of termite-inspired robots was demonstrated by
Harvard University
Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Founded in 1636 as Harvard College and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of high ...
researchers in 2014, following four years of development. Their engineering was inspired by the complex mounds that
termites
Termites are small insects that live in colonies and have distinct castes (eusocial) and feed on wood or other dead plant matter. Termites comprise the infraorder Isoptera, or alternatively the epifamily Termitoidae, within the order Blattod ...
build, and was accomplished by developing simple rules to allow the robots to navigate and move building blocks in their environment. By following these simple rules, the robots could construct complex structures through a process called ''
stigmergy
Stigmergy ( ) is a mechanism of indirect coordination, through the environment, between agents or actions. The principle is that the trace left in the environment by an individual action stimulates the performance of a succeeding action by the sam ...
'', without requiring constant human instruction or supervision.
Background
Social insects such as termites are capable of constructing elaborate structures such as mounds with complex tunnel systems. They are capable of doing so without an overall plan for the design of a structure, without directly communicating information with each other about how to construct a structure, and without a leader to guide them in constructing a specific structure.
Roboticist
Robotics is an interdisciplinary branch of computer science and engineering. Robotics involves design, construction, operation, and use of robots. The goal of robotics is to design machines that can help and assist humans. Robotics integrat ...
s have been interested in the problem of whether robots can be designed with the limited sensory and motor capabilities of insects such as termites and yet, by following simple rules, construct elaborate and complex structures.
Robots
As part of the TERMES project, the Harvard team designed each robot to perform a few simple behaviors: to move forward, move backward, turn, move up or down a step the size of a specially designed brick, and to move while carrying a brick on top of it. To perform these locomotor behaviors, each robot was equipped with
whegs
Whegs (''wheel-legs or wing-legs'') are mechanisms for robot locomotion. Whegs use a strategy of locomotion that combines the simplicity of the wheel with the obstacle-clearing advantages of the foot.
Whegs were pioneered at the Biologically In ...
. To detect features of its environment and other robots, each robot was equipped with the following sensors: seven infrared sensors to detect black and white patterns for navigation; an
accelerometer
An accelerometer is a tool that measures proper acceleration. Proper acceleration is the acceleration (the rate of change of velocity) of a body in its own instantaneous rest frame; this is different from coordinate acceleration, which is acc ...
to detect tilt angle for climbing; and five
ultrasound
Ultrasound is sound waves with frequencies higher than the upper audible limit of human hearing. Ultrasound is not different from "normal" (audible) sound in its physical properties, except that humans cannot hear it. This limit varies ...
sonar
Sonar (sound navigation and ranging or sonic navigation and ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, measure distances (ranging), communicate with or detect objects on o ...
detectors for determining distance from the perimeter and to nearby robots. To lift, lower, and place the specially designed bricks, each robot had an arm with a spring-loaded gripper to hold a brick while carried. The project's specially designed construction bricks were 21.5 cm × 21.5 cm × 4.5 cm, which was bigger than the footprint (17.5 cm × 11.0 cm) of the robots.
Constructing structures
During the Harvard trials, groups of termite-inspired robots constructed structures by stigmergy. That is, instead of directly communicating with each other, the robots detected features of their environment and followed simple rules for moving and placing bricks in response to the configuration of bricks that existed at a given time. The rules for constructing a given structure were designed to guarantee that different structures emerged depending on the number of robots involved and on the initial placement of bricks.
The TERMES robots constitute a
proof of concept
Proof of concept (POC or PoC), also known as proof of principle, is a realization of a certain method or idea in order to demonstrate its feasibility, or a demonstration in principle with the aim of verifying that some concept or theory has prac ...
for the development of relatively simple teams of robots that are capable of constructing complex structures in, for example, remote or hostile locations. The Harvard researchers who built the initial termite-inspired robots have speculated that future robots could be designed to build a base for human habitation on
Mars
Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, only being larger than Mercury. In the English language, Mars is named for the Roman god of war. Mars is a terrestrial planet with a thin at ...
in preparation for the arrival of human astronauts. More immediate possibilities include teams of termite-inspired robots that are capable of moving sandbags and building
levees
A levee (), dike (American English), dyke (Commonwealth English), embankment, floodbank, or stop bank is a structure that is usually earthen and that often runs parallel to the course of a river in its floodplain or along low-lying coastli ...