Insect feet inspired concepts soft touch grippers with dynamically adjustable grip strength
The emerging field of soft robotics aims at using soft structures and materials in robots and automation. While the same wide ranging functionality as for traditional robots is desirable, using soft structures and materials can bring complementary function and assets that are inherently inaccessible in traditional robots. An important advantage is that the human – robot interaction can be safer and gentler than with hard robots. In the future, soft robots may be used in the care for the elderly or infirm or in production lines with humans working alongside robots. A key area in soft robotics is therefore to establish new concepts for dynamically adjustable, flexible soft gripping that is compatible with humans. Our proposal addresses three of the core research areas:
- The invention of soft materials with dynamically controlled actuation capabilities
- The design and fabrication that allows the integration of functional soft materials into support soft materials in a way that actuation and sensing is made possible
- The integral design of soft actuators/soft materials support that comply to an object shape.
We investigate two of the key research questions:
- The opportunities that arise from using soft materials using natural models and transpose the mechanical functionalities to softened, simplified technical counterparts
- Safe human / robot interaction by finding chemical concepts so that the actuation stimulus is changed from currently UV-light to visible and thus safe light.
While soft robotic concepts are in their infancy in production science, in nature, gripping (or adhesion) mechanisms have evolved over thousands of years and are found in an almost unfathomably variety, precision and specialization. We will use examples from the insect world as inspiration for grip joint design with new soft functional materials: Gripping strength will be modulated using both mechanical and light controlled leverages. Insect feet are plausible structural models for soft grippers; from these, we will abstract a multi-part gripper: Soft gripping modules that control position and force of the grip combined with a semi-hard or soft supporting structure. From the analysis of insect morphology, we will arrive at models, which allow the simulation of mechanical functionality and movement controllability. Soft functional engineering elements will be systematically integrated in a hierarchical degree of softness. Controlled dynamic actuation will arise from new photomechanical materials that change their shape in dependence of their illumination status. Coupling these photo switchable materials with bio-inspired dry-adhesives and touch sensitive layers will enable the fabrication of a soft, dynamic gripping module, which serves as the direct contact module with the object to be gripped. The general principles derived in the project will guide future design strategies for soft robotics.