Design, Fabrication and Characterisation of a Fully Elastomeric Soft Sensor

Soft sensing refers to the technology for interaction and perception within the constantly growing field of soft robotics. It has been developed in response to the need for safe, precise and adaptive interaction with its environment. Soft sensing has advanced beyond the scope of industrial applications, spanning into dynamic applications such as surgery, drug delivery and health care. Research in developing soft sensors is becoming a rising focus in soft robotics due to the importance of interactions between humans and their environment in a robotic system. Active feedback is needed for soft robots to achieve accurate controls and safe interactions. However, there are still gaps in current research on soft sensors, for example, the lack of comprehensive study on the properties of soft materials and adaptive design of soft sensors. This thesis examines the developments of soft robotics and soft sensors. A comprehensive review of state-of-the-art soft sensor research highlights the fundamentals of soft sensors in terms of materials, fabrication and applications. The literature review summary suggests that a fully elastomeric soft sensor may be a potential candidate to fill the gap in the adaptivity and stretchability of soft sensors. A highly stretchable and electrically conductive soft material is studied to fabricate the target soft sensor. A new design is applied to propose a conductive polyacrylamide hydrogel, and a new experimental approach is conducted to characterise the proposed hydrogel. Both the mechanical and electrical properties of the conductive hydrogel are studied simultaneously. A fully elastomeric soft sensor is designed, fabricated, evaluated, and demonstrated based on the proposed soft material. The fully elastomeric soft sensor is then extended in application to two case studies. The thesis presents a complete design procedure, fabrication and characterisation of new soft material and a complete methodology of design, fabrication, testing and application of a fully elastomeric soft sensor.