The COVID-19 pandemic imposes an increasing demand for service robots as a substitute for humans to conduct various types of work in contaminated areas. Such work includes logistics, patient care, and disinfection, which can reduce the risk of human exposure to the highly contagious and deadly virus. This paper presents the design and development of Smart Cleaner, which is a new cost-effective autonomous indoor disinfection robot. It integrates a wheeled mobile robot platform and a hydrogen peroxide atomization device for automated disinfection operation in the complex indoor environment. Through the system integration of various hardware components and software programming, a prototype of the disinfection robot has been fabricated for experimental investigation. A simulation study of the drymist hydrogen peroxide disinfection model was carried out to understand the diffusion of disinfectant in a room environment. The effectiveness of the developed robot was verified in practical scenarios, such as hospital, hotel, office, and laboratory. The effect of disinfection was validated by a qualified third-party testing agency. Results demonstrate the high efficiency of the developed disinfection robot dedicated to autonomous indoor disinfection work.

Autonomous magnetic catheterization has become a promising technology for next-generation minimally invasive cardiovascular surgery. In this paper, a novel homocentric variable-stiffness magnetic robotic catheter (HVS-MRC) is presented. This device is controlled by a multi-arm robot-assisted catheterization system for use in radiation-free coronary ultrasound intervention. The uniqueness of the HVS-MRC is the generation of variable stiffness through the telescopic motion of three homocentric components with embedded internal magnets. These components can be used to achieve multiple curvatures and large deflections ( $>$ 120 degrees) under a magnetic wrench provided by an external mobile magnet module (EMMM) to adapt to the complex coronary environment. The variable-stiffness kinematics modeling, multivessel selection strategy, and preoperative surgical planning of the proposed magnetic robotic catheter are established. Meanwhile, an extracorporeal mobile ultrasound module (EMUM) is adopted to intraoperatively localize the catheter's in-plane motion with a dominant visual/force feedback controller. A hierarchical relative control scheme is proposed based on the relative Jacobian method to synchronize the motions of the multi-arm robot-assisted catheterization system. The overall performance is evaluated with an in vitro human-sized coronary arterial phantom with challenging anatomical variabilities. The results reveal that the HVS-MRC exhibits a high-accuracy intervention performance (average error of 1.52 $ \pm$ 0.35 mm) with smoother steering compared with conventional catheters. High synchronization with a low ultrasound target loss rate (15.8%) and constant-force tracing (2.50 $\pm$ 1.02 N) of the multi-arm robot-assisted catheterization system demonstrate promising application potential in radiation-free autonomous ultrasonographic coronary intervention operations.

This article presents the design and testing of a novel passive polishing end-effector with adjustable constant force and wide operating angle, which enables adjusting the polishing effect and maintaining the constant contact force for polishing surfaces of large curvature. The constant-force mechanism is obtained by composing a positive-stiffness mechanism and a negative-stiffness mechanism. The magnitude of the constant force can be regulated by adjusting the preloading displacement of the positive-stiffness mechanism. The constant force is provided at a wide tilted angle of the end-effector because the connected counterweight compensates for the gravity effect. The working principle and mechanism design of the proposed polishing end-effector are presented. Based on finite-element analysis simulation, an optimization study is carried out to determine the structural parameters of the constant-force mechanism with expected performances. A prototype of a polishing end-effector is fabricated for experimental tests to evaluate its performance and verify the proposed concept design. The results indicate that the reported polishing end-effector exhibits adjustable constant force and wide operating angle for practical applications.

Rather than using longitudinal “muscle” as in biological inchworm, the existing magnetic active elastomer (MAE)-based inchworm robots utilize magnetic torque to pull and push the soft body, which hinders its locomotion mobility. In this paper, a new pre-strained MAE inchworm millirobot with micropillars is proposed. The pre-strained elastomer serves as a pre-load muscle to contract the soft body, and the micropillars act as tiny feet to anchor the body during the locomotion. The proposed magnetic inchworm robot features a simple fabrication process that does not require special magnetization equipment. For the first time, the pre-load muscle is introduced in the design of magnetic inchworm robots, making it more like a real inchworm in terms of locomotion mechanism. The locomotion principle and parametric design for the desired locomotion performance have been investigated. Experimental results show that the fabricated magnetic inchworm robot (size: 10 mm × 5 mm, micropillars length: 200 µm, and mass: 262 g) can locomote on a smooth acrylic surface (roughness of 0.3 µm) at the speed of 0.125 body lengths per second, which is comparable with the existing magnetic inchworm robots. Moreover, the locomotion capabilities of the inchworm robot on wet surfaces and inclined planes have been verified via experimental studies.