“Nature’s ready-made robot platforms.” That’s how a new paper from researchers at Singapore’s Nanyang Technological University describe insects — it’s excellent shorthand for the level of “playing god” we have attained, whether you find it fascinating or abhorrent. Of course, aside from simply demonstrating man’s mastery over creation, this type of work is immensely important in fields ranging from entomology and neuroscience to prosthetics engineering.
The paper, published Wednesday in the Journal of the Royal Society Interface, describes a system for controlling an insect nervous system that goes considerably beyond the likes of Roboroach and other, more scholarly efforts.
“To the best of our knowledge, this paper presents the first demonstration of living insect locomotion control with a user-adjustable walking gait, step length and walking speed,” reads the abstract.
Previous work has created cockroaches and spiders that can be spurred into motion and even steered, but using a more high-level style of control: inducing what amounts to an irresistible urge to walk forward, rather than causing limbs to move of their own accord, Dr. Strangelove style. The new study successfully demonstrates the latter, though in a somewhat limited fashion.
The insect is a giant flower beetle, Mecynorhina torquata; its huge body makes attaching leads easier (just try it on Drosophila). The team first closely observed the muscles and tension patterns involved in various types of movement using motion capture and good old dissection, then wired up those muscles and stimulated them with pulse-width modulated signals generated on a nearby (but not on-beetle) microcontroller.
Only the front two legs were wired for the purposes of this experiment, which limited the types of locomotion available, but the researchers note that two-legged gaits do occur naturally in hexapod creatures.
The process of innervating the leg muscles with preset rhythms was highly successful, write the researchers, and the results advance the state of knowledge in the more traditional fields of insect behavior and anatomy, as well as showing the viability of this technique in the creation of an “insect-computer hybrid robot.”
Such chimerae have numerous advantages over man-made robots of a similar size and build, which the researchers list with relish — you can almost hear the pens scraping on grant requests to investigate things like using insect legs instead of 3-D printed ones, or powering the hybridizing implants via energy harvesting in the animal itself.
It’s creepy, sure. But it’s also deeply fascinating and, with a little more work, eminently practical. Research is already underway to equip cockroaches with directional microphones and tracking units, allowing them to skitter through a disaster area, compelled artificially to move toward the voices of trapped humans. And why deploy a $10,000 drone when a dragonfly with a $100 cybridizing backpack tapping into its nervous system will do?
No doubt the latter possibility is attractive to deep-pocketed funding agencies like DARPA, which is why they are almost certainly already writing checks to those pursuing it and options like it.
Incidentally, the paper, by Feng Cao, Chao Zhang, Hao Yu Choo and Hirotaka Sato, is very readable, even without much technical knowledge — check it out and be amazed.