Scientists at Tufts University are to develop ‘soft and squishy’ chemical robots that can squeeze into spaces down to 1cm, then morph back into something 10 times larger, and ultimately biodegrade, as part of a $3.3 million contract from DARPA.

Constructed mainly from rigid materials, today’s robots are unable to navigate complex environments with openings of arbitrary size and shape.

Based on the performance capabilities of the Manduca Sexta caterpillar, such as its flexibility, climbing ability and scalability, the Tufts team aims to develop ‘chembots’ that will be able to access confined and complex spaces, follow cables, ropes or wires and climb trees or other branched structures. The growth of the Manduca Sexta caterpillar also interested the researchers. From hatching to the end of its larval stage, the caterpillar grows 10,000 fold in mass using the same number of muscles and motor neurons.

Key to success of the chembots will be the use of new biomaterials. The initial chembots will be built with existing synthetic soft materials and actuators; however, the next stage of the project will use novel soft bionic composites that will be biocompatible and biodegradable.

Once in place, the energy-efficient chembots could survey the area, then morph to accomplish their task. For example, they might gain entry to an improvised explosive device to gather information, or potentially disable the device. Other applications could include landmine detection, search and rescue in hazardous conditions, and biomedical diagnosis. Scientists also hope the chembots will be capable of carrying miniature or microversions of themselves for access to areas on an even smaller scale.

On completion of their mission, the chembots will literally disappear.

Commenting on the project, Dr Mitchell Zakin, DARPA program manager for the ChemBots program, said: “DARPA’s ChemBot program represents the convergence of soft materials chemistry and robotics. It is an entirely new way of looking at robots, and could someday yield great technological advantage for our armed forces.”