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Abstract Artificial active colloids are an active area of research in the field of active matter and microrobotic systems. In particular, light‐driven semiconductor particles are shown to display interesting behaviors ranging from phototaxis (movement toward or away from a light source), rising from the substrate, interparticle attraction, attraction to the substrate, or other phenomena. However, these observations involve using multiple different designs of particles in varying conditions, making it unclear how the experimental parameters, such as pH, peroxide concentration, and light intensity, affect the outcomes. In this work, a peanut‐shaped hematite semiconductor particle is shown to exhibit a rich range of behavior as a function of the experimental conditions. The particles show rising, sticking, phototaxis, and in‐plane alignment of their long axes perpendicular to a magnetic field. A theoretical model accounting for gravity, van der Waals forces, electric double layer interactions with the glass surface, and self‐diffusiophoresis is formulated to describe the system. Using experimental data on the dependence of particle behavior on pH and ionic concentrations, the model captures the interplay of competing effects and explains many of the observed behaviors, providing insight into the relevant physical phenomena and how different environmental conditions can lead to such a rich diversity of behavior. 

Developing microrobotic systems for accurate and fast manipulation of microobjects or living cells has the potential to significantly advance biomedical and microfabrication applications. Despite recent progress in this field, comprehensive multistimuli responsive, fast, and precisely controllable microrobots remain limited. In this study, automated position and speed control of acoustically powered, bubble‐based, magnetically steerable microrobots is demonstrated, along with micromanipulation of mammalian cells using these microswimmers. Enhanced control of the microswimmers is achieved by designing and implementing a closed‐loop control system that guides the microrobots along a predetermined path while modulating their speed by adjusting the acoustic frequency near the resonant value. The microrobots are guided to cells, enabling cell manipulation by pulling them with the microrobots. Overall, the results highlight the capability and controllability of these magnetically and acoustically responsive microrobots for future cell‐based applications, including manipulation, delivery, and microsurgery.