When Project Daedalus was being designed back in the 1970s, the members of the British Interplanetary Society who were working on the starship envisioned it being maintained by ‘wardens,’ robots that would keep crucial systems functional over the 50-year mission to Barnard’s Star. Invariably, that calls up images of metallic machines, stiff in construction and marked by a certain ponderous clumsiness. True or false, it’s a view of robotics that has persisted until relatively recently.
But if you’re going to do long-term maintenance on a starship, you’d better be more flexible. And that makes a Tufts initiative interesting not just from a space perspective but for applications in medicine, electronics, manufacturing and more. The Biomimetic Technologies for Soft-bodied Robots project aims to produce machines that draw on the model of living cells and tissues. Five Tufts departments will work with a $730,000 grant from the W.M. Keck Foundation to get the job started.
Check out what’s going on at the university’s Biomimetic Devices Laboratory. The researchers here are calling for us to stop evaluating the line between living and mechanical on the basis of materials. “Many machines incorporate flexible materials at their joints and can be tremendously fast, strong and powerful,” says Tufts biology professor Barry Trimmer, “but there is no current technology that can match the performance of an animal moving through natural terrain.”
Trimmer is a neurobiologist whose work with caterpillars feeds directly into the robot concept. How do you build a simple machine that can move flexibly without joints? Like caterpillars, the new robots are to be soft, but unlike them, the robots will also be capable of collapsing into small volumes, and unlike today’s robots, they’ll be able to crawl along wires or burrow themselves into tiny spaces to do their work. Thus does biology meet nano-fabrication and bioengineering, with results that may prove exceedingly useful for long-haul space missions.
Back to the Daedalus wardens for a moment. They were designed not only to test and repair key onboard systems, but also to operate thousands of kilometers away from the ship as needed, coordinating a variety of experiments through the ship’s main computer. But they were envisioned as weighing five tons apiece and in the thinking of that era, would have been incapable of the kind of adaptive — one could say ‘evolutionary’ — behavior that is suggested by flexible hardware and genetic algorithms.
For software that generates variations in its own code and tests a variety of mutations has been under study for some time — look at the work Jordan Pollack and Hod Lipson have done at Brandeis, for example. Wedding genetic algorithms with a new flexibility in robotic structure promises great things for missions that must proceed without human intervention. Specialized robots will continue to fly on our space missions, but in forms that look less and less like the Daedalus wardens.
And incidentally, if you want to see those Daedalus wardens up close, the best reference is T. J. Grant, “Project Daedalus: The Need for On-Board Repair,” in A. R. Martin, ed. Project Daedalus Final Report. Supplement to the Journal of the British Interplanetary Society, 1978, pp. S172–S179.