High‐Load Shape Memory Microgripper with Embedded Resistive Heating and Magnetic Actuation

Abstract Magnetically actuated soft grippers find extensive applications in robotics due to their rapid response, biological safety, and wireless control capabilities. However, these systems often require a continuously applied magnetic field during both the capture and release processes, which reduces load capacity and makes gripping ferromagnetic objects challenging. Here, an electrothermal‐magnetic actuated shape memory (EM‐SMP) microgripper is developed. By incorporating Fe₃O₄ particles into the shape memory polymer (SMP) and embedding resistive wires, the microgripper can respond to both electric current and magnetic field. The high thermal conductivity of the composite material, coupled with microscale dimensions achieved via femtosecond laser processing, significantly enhances the response speed (≈0.9 s). The magnetic field is applied only to open the gripper, while closure is realized through the electrothermal‐triggered shape memory effect, allowing sequential closure to safely grip delicate soft objects and magnetic objects without magnetic interference. Upon cooling, the closed state of the SMP gripper locks in place without energy consumption. Furthermore, the claw‐shaped design allows the gripper to enclose larger objects during grasping, thereby improving the load‐to‐weight ratio (≈2380). This gripper demonstrates broad application potential, effectively performing grasp and release tasks across diverse materials, sizes, shapes, states, and extreme environmental conditions (acidic and alkaline).