An inter­sec­tion of math and bio­logy: Clams and snails inspire robot­ic dig­gers and crawlers

(Above a brief video of Hosoi talk­ing about her research at the 2013 SIAM Annu­al Meet­ing.) That is one of the reas­ons Anette Hosoi, pro­fess­or of mech­an­ic­al engin­eer­ing at the Mas­sachu­setts Insti­tute of Tech­no­logy, stud­ies snails. Snails can move in any dir­ec­tion — hori­zont­ally, ver­tic­ally, and upside down — on vari­ous sur­faces, be it sand, shells, tree barks or slick walls and smooth glass. One of the reas­ons for this is the sticky sub­stance on their under­bel­lies, which acts as a power­ful lub­ric­ant and reduces fric­tion dur­ing move­ment. By study­ing and adapt­ing the bio­lo­gic­al prop­er­ties of the snail to robot­ic devices, Hosoi’s group has been able to cre­ate a ​“RoboS­nail,” which can climb walls and stick to over­head sur­faces much like its liv­ing coun­ter­part. Such a device can have poten­tial uses in invas­ive sur­gery and oil well drilling, among oth­er applic­a­tions. Anoth­er organ­ism of interest to Hosoi is the razor clam, which has an amaz­ing abil­ity to dig and wedge itself; it can bur­row up to 30 inches in the sand. Hosoi’s ​“Rob­oClam” has been developed with the inten­tion of under­stand­ing the organism’s beha­vi­or and mech­an­ics as well as to explore the pos­sib­il­ity of auto­mated dig­ging devices that use less energy than cur­rent tech­no­logy and equip­ment. The research­ers found that while dig­ging, the clam’s up-and-down move­ment accom­pan­ied by open­ing and clos­ing of its shell turns sand into the con­sist­ency of liquid quick­sand. This in turn allows the clam to move quickly through the sand. Sim­il­ar to the human ver­sion, the Rob­oClam vibrates, chan­ging the sol­id seabed into flu­id, allow­ing a worm-like foot to push down. Clam-inspired robot­ic dig­gers could find use as auto­mat­ic teth­ers and light­weight low-cost anchor­ing devices for small robot­ic sub­mar­ines and even large ships and oil plat­forms. Devices that bur­row into the seabed could also poten­tially be used as det­on­at­ors for under­wa­ter mines. Hosoi is not alone in look­ing to bio­logy to instruct robot­ics devel­op­ment. Engin­eers around the world are turn­ing to nat­ur­al organ­isms like insects, fish and turtles to inspire the design of robots cap­able of per­form­ing spe­cif­ic tasks that auto­mated devices have tra­di­tion­ally been unable to achieve. Mim­ick­ing nat­ur­al organ­isms can also aid in improv­ing the effi­ciency of many applic­a­tions that are ener­get­ic­ally expens­ive, since bio­lo­gic­al entit­ies per­form the same tasks with much high­er effi­ciency. It is import­ant to not only copy the anim­als, but also to under­stand the bio­logy of their mech­an­isms in order to take away the key fea­tures that allow them to do what they do. These types of bio­mech­an­ic­al stud­ies have led to a mutu­ally bene­fi­cial part­ner­ship between math­em­aticians and bio­lo­gists. Bio­lo­gists can inform math­em­at­ic­al sci­ent­ists as a gold­mine of data is emer­ging as bio­logy becomes more and more quan­ti­fied. Math­em­aticians, in turn, can employ the tools of engin­eer­ing and com­pu­ta­tion to ana­lyze this data and offer new insights into the way anim­als move. Source: Soci­ety for Indus­tri­al and Applied Math­em­at­ics (SIAM)