This article presents a bioinspired pneumatic soft actuator designed to achieve asymmetrical spatiotemporal deformations, inspired by the dynamic motion of human walking. The actuator’s key innovation is a half-crossing structure that enables controlled airflow to produce complex bending and linear motions using only two air tubes. This design significantly reduces structural complexity and energy consumption compared with conventional soft actuators, which often require multiple air channels to achieve similar deformations. The actuator mimics the stance and swing phases of locomotion, allowing precise multidirectional movements, including forward, backward, and turning motions. A passive feedforward control strategy further enhances movement flexibility without the need for complex feedback systems. Experimental results demonstrate the actuator’s adaptability and efficiency when integrated into a hexapod robot, with optimized performance through adjustments in air pressure and cycle duration. This work offers a versatile and energy-efficient solution for adaptive locomotion in soft robotics, advancing the field through a novel approach to actuator design.
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