Three-Dimensional-Printed Carnivorous Plant with Snap Trap

Three-dimensional (3D) printing has a variety of applications, from efficient iterations of engineering designs to fabrication of tissues for regenerative medicine. In soft robotics, 3D-printed functional materials can be used to mimic biological functions. Soft robotics overcomes some of the limitations of traditional rigid-body robotics through the ability to conform to different shapes and to be pneumatically controlled. Although soft robotics has been studied extensively by curing elastomers, 3D printing of flexible soft robotic components remains a challenge. Thus, we propose a method to easily fabricate a soft robotic device by using a stereolithographybased 3D printer and a flexible resin. Here, we have designed a device with a soft material composition, a pneumatic control device, and an integrated touch-based sensor to actuate a grasping motion in response to an object coming in close proximity to the sensor, mimicking the natural motion of a carnivorous plant. Characterization of the geometric and kinematic features of the plant leaves shows the dependence of the plant leaves’ opening and closing motion on the touch signal provided. In the future, such soft hybrid robotic structures can be useful for biosensing, smart clothes, prosthetic designs, and other soft robotics applications.