Preparation of biological samples for further processing or analysis is generally performed manually by means of standard mechanical tools such as scalpels or biopsy punches. While this approach is uncomplicated and swift, it entails constraints such as low, operator-dependent cutting accuracy and reproducibility. Tissue segments surrounding the cut may further suffer mechanical and thermal damage due to shear forces and friction between tool and sample. These hindrances affect procedures both in the laboratory environment as well as within clinical settings. A system has been developed leveraging robotic positioning and laser light for precise, controlled, and contactless tissue ablation, and providing a concise and intuitive graphical user interface. Additionally, sterility of the process is demonstrated, a paramount element for clinical application. The proposed process does not require sterilization of the robotic components or the lasers, easing a prospective integration into existing workflows. In the context of this work, mainly cartilage repair surgery is targeted. The proposed system allows for highly accurate and reproducible shaping of the cartilage lesion area as well as its corresponding engineered cartilage graft, possibly leading to better and faster integration at the defect site. Promising results could be obtained in a first test series with human cartilage samples, validating the functionality of the preparation system and the feasibility of the sterility concept.