MEMS-based micromanipulation with pseudoparallel rotary comb drive actuators and sensors

This work presents a MEMS microgripping device integrated with cooperating actuators in a pseudoparallel configuration, as a novel method to address modern micro- and nanomanipulation applications. Pseudoparallel rotary comb drives, arranged in a newly conceived floating-centered layout, are proposed as a route to multifunctional, multioperation micromanipulators. The concept is demonstrated through a modular multilink device, in which functional units such as actuators and sensors can be added or removed without altering the main structural layout. The design is also easily scalable, as it exploits electrostatic actuation, more efficient at small scales, and is compatible with standard silicon-on-insulator MEMS processes. To validate the concept, a prototype was fabricated and tested across multiple scenarios, accompanied by numerical simulations on a digital twin. Results highlight improved actuation and sensing capabilities compared to previous architectures. Pseudoparallel modules increased tip motion up to 14.4% and force exertion up to 30.5% relative to the non-parallel configurations without altering the four-bar kinematics, while adding actuation functionalities and enabling simultaneous motion and force feedback, with achieved sensitivities of 6.26 fF/um and 12.44 fF/uN, respectively. The system demonstrates compactness, versatility, and modularity, making it promising for applications in micro/nanosurgery, biological manipulation, and robotic microassembly.