A liquid metal robot driven by hybrid-fluid

Since the 20th century, robots have been widely used in many fields such as manufacturing and life services. Traditional rigid robots are limited by degrees of freedom and are difficult to adapt to the dynamic and unstructured complex environment. Soft robots have attracted wide attention in recent years due to their flexibility and adaptability to the surroundings. Room temperature liquid metal combines the perfect properties of liquid and metal, such as excellent thermal conductivity, electrical conductivity, fluidity and low toxicity etc. Meanwhile, liquid metal is identified to be very useful in robotics due to its inherent flexibility. At present, the liquid metal can mainly be driven by electrical field, magnetic field and chemical reaction, all of which need to be carried out in solution environments. From an alternative, a rolling robot is proposed based on gallium-based liquid metal driven by hybrid-fluid. The movement of the liquid metal in the spiral tube alters the center of gravity of the device, pushing the entire robotic system to achieve its rolling locomotion, which frees the motion of liquid metal from the solution environment where its locomotion generally relies on. Besides, the hybrid-fluid driving can be achieved by thermal driving and chemical reaction, respectively. In the present research, the principles of two different hybrid-fluid driving mechanisms were interpreted. Prototyping devices were designed, and a series of conceptual experiments were conducted to clarify the factors affecting the motion of the device, which demonstrate the feasibility and prospects of hybrid-fluid driving robot. The present results are expected to be valuable for developing future of soft robotics technologies.