LegoBot: Modular, Compact, Device-Agnostic Robot for Endovascular Catheter and Guidewire Manipulation in Stroke Thrombectomy

State-of-the-art endovascular robots are often limited by coupled translation–rotation actuation, narrow compatibility with off-the-shelf devices, and fixed architectures that are difficult to reconfigure for multidevice procedures. These limitations are especially restrictive in neurovascular intervention, where long working lengths, tortuous anatomy, and coordinated manipulation of multiple catheters and guidewires are frequently required. In this work, we present LegoBot, a modular, compact, device-agnostic robot for neurovascular catheter and guidewire manipulation. First, we design a decoupled two-degree-of-freedom (2-DOF) actuation mechanism together with an instrument-agnostic adjustable clamping mechanism, enabling independent or simultaneous instrument translation and rotation while accommodating off-the-shelf devices with diameters ranging from 0.33 to 3 mm. Second, we present the mechatronic design of a modular catheter robot with interchangeable adapters for different instruments, which support module-level device exchange. We also design a module coupler that connects adjacent robotic modules for multi-instrument actuation and improves rotational torque transmission through long, compliant instruments. Benchtop characterization of the proposed 2-DOF mechanism showed peak insertion force up to 5.3 N and rotational torque up to 8.4 mN$\cdot$m, exceeding reported clinical requirements. Phantom studies demonstrated a two-module (4-DOF) configuration for diagnostic angiography and a three-module (6-DOF) configuration for aspiration thrombectomy, including successful clot aspiration in a neurovascular phantom.