Autonomous Mobile Robotic System for 3D Surface Scanning in Forensic Medicine

Overview

This article presents a novel mobile and autonomous robotic system designed for comprehensive external surface scanning of corpses in forensic medicine. The system integrates a lightweight robotic arm with an RGB-D camera mounted on a mobile base, enabling flexible positioning and autonomous scanning without manual intervention. Experimental evaluations demonstrate the system's capability to optimize scanning paths and adapt to environmental constraints, enhancing documentation efficiency and accuracy.

Background

Accurate documentation of corpses is critical in forensic medicine for medico-legal investigations and legal proceedings. While post-mortem imaging modalities like CT and MRI provide detailed internal anatomy, they lack detailed surface information such as skin color and wound characteristics. Traditional 2D imaging and manual 3D scanning methods have limitations in automation, cost, and flexibility. Robotic systems offer potential for automated, time-efficient, and infection-minimizing surface documentation but often require fixed installations and manual path planning. There is a growing need for low-cost, mobile, and autonomous solutions to improve forensic surface documentation.

Data Highlights

The system uses a lightweight 6-joint robotic arm (UR3) mounted on a differential drive mobile base equipped with an RGB-D camera (Azure Kinect). A configuration space analysis is performed to optimize scanning paths, minimizing the number of robot base positions while maximizing body coverage. Path planning utilizes an A* algorithm to navigate environmental constraints such as obstacles and couch height. The workflow includes an initial exploratory scan to assess body pose and environment, followed by autonomous scanning and post-processing to generate comprehensive 3D surface models.

Key Findings

• The autonomous system can recognize body pose and environmental constraints to plan optimal scanning paths without manual input.
• The mobile base extends the operational range of the robotic arm, allowing flexible positioning around the body.
• Configuration space analysis enables balancing scanning time and surface resolution by minimizing robot base repositioning.
• The RGB-D camera provides simultaneous color and depth data critical for accurate surface documentation.
• Experimental validation in laboratory settings confirms the system's feasibility for forensic surface scanning applications.
• The system addresses limitations of existing fixed robotic setups by offering mobility, autonomy, and reduced preparation requirements.

Clinical Implications

This autonomous robotic scanning system can improve forensic documentation by providing comprehensive, high-resolution 3D surface data with minimal manual intervention. Its mobility and adaptability make it suitable for various forensic environments, potentially reducing workload and infection risk. Integration with existing post-mortem imaging modalities can enhance multi-modal forensic records, supporting medico-legal investigations and court evidence.

Conclusion

The presented mobile and autonomous robotic system offers a promising advancement in forensic surface scanning by combining flexibility, automation, and detailed 3D documentation. This approach may significantly enhance the efficiency and quality of corpse surface documentation in legal medicine.

References

1. Sieberth et al. 2021 -- Cost-effective 3D surface scanning using a spoke rod with multiple cameras
2. Virtopsy Project 2010 -- Multi-modal 3D color documentation of corpses
3. Universal Robots UR3 -- Robotic Arm Specifications
4. Microsoft Azure Kinect -- RGB-D Camera Specifications
5. A* Algorithm 1968 -- Path Planning Method