Soft-logic: design and thermal-comfort evaluation of smart thermoregulatory fabric with pneumatic actuators

As homeotherms, human beings rely on garments to maintain thermal equilibrium and comfort. When clothing cannot meet their thermal comfort requirements, they have to use the heating, ventilation, and air conditioning system (HVAC) for thermal regulation, which causes huge energy waste and environmental pollution. Developing a thermoregulatory garment with excellent thermal comfort is undoubtedly an urgent demand for smart textile and advanced materials. In this article, we propose an air-driven structure, called soft-logic fabric, with outstanding thermoregulation, inspired by the thermal management mechanism of birds' plumage. Experiments reveal that the thermal resistance of soft-logic samples increases by 15 times after inflation, which can effectively reduce heat loss of the human body. The insulation performance of the inflated soft-logic fabric system is higher than that of high thermal-efficiency polyester wadding (thickness = 8 mm) and that of the wool blend fabric (thickness = 4.52 mm, 80% wool, 20% polyester). A 20 cm2 sample can lift an object 270 times heavier than its own weight after hand-pumping for only up to ten times. Based on the predicted mean vote (PMV) and the predicted percentage of dissatisfied (PPD) model, this design can create a thermal comfort setpoint range 3.84 times wider than that of classic fabrics. Furthermore, an automatic inflation control system is developed for inflatable thermoregulation garments. This study opens up a new path for the design of intelligent thermoregulatory fabrics and personal thermal management.