Task-Oriented Biomedical Microrobots: Access, Working Environment, Actuation, Body Design, Detection and Control

Biomedical microrobots are often classified by propulsion, materials or fabrication, but clinical translation depends on whether a device can complete a task in a specific biological setting. This review frames biomedical microrobots as task-oriented execution systems. Access and the working environment define the first constraints; actuation and body design convert inputs into useful local work; detection and control close the loop by linking measured states to the next action. Examples from vascular, gastrointestinal, pulmonary, luminal, cellular and biofilm-facing systems show that route, medium, motion, retention, payload function, imaging and post-task fate are coupled rather than separate design labels. Magnetic fields can resist flow or guide motion in confined anatomy, acoustic and optical inputs supply penetrative or local energy, and chemical or biological motors use cues from the surrounding medium. Body design then determines whether movement remains compatible with contact, release, sensing, retrieval and biocompatibility. By focusing on task execution rather than platform identity, this review clarifies what should be preserved in test models, what should be measured, and how fair comparisons can be made before translation.