Soft robots, built from flexible materials, excel at navigating uneven terrain and handling delicate objects, but they typically still depend on electronic sensing and control. A team led by Oxford's Department of Engineering Science, publishing in Advanced Materials, has demonstrated a class of fluidic robots that dispense with electronics, motors and computers altogether, generating complex rhythmic movement from nothing but air pressure and clever physical design.
The key innovation is a small modular block, a few centimetres across, that performs mechanical tasks the way an electronic component handles current. Depending on configuration, the same unit can actuate like a muscle, sense pressure or contact like a touch sensor, or switch airflow like a valve or logic gate. Assembled like building bricks, the units formed shoebox-sized tabletop robots that could hop, shake or crawl, and in one configuration a single unit combined all three roles to generate rhythm on its own under constant pressure.
Most strikingly, when several units were linked, their movements synchronised spontaneously through physical contact with the ground, much as fireflies fall into flashing unison, an emergent behaviour previously observed in nature but difficult to engineer. Demonstrators included a shaker robot that sorted beads and a crawler that detected a table edge and stopped itself, pointing towards robots whose intelligence is embodied in their structure rather than their software.