Researchers at Harbin Institute of Technology have developed a multifunctional frequency modulated continuous wave (FMCW) LiDAR that can perform high-precision 3D imaging and simultaneously measure multiple physical parameters, including environmental temperature, gas concentrations, and liquid density. This innovation addresses the growing demand for integrated sensing systems in new energy vehicles and spacecraft, where safety and efficiency are paramount.
The new LiDAR system, detailed in a paper published in Light: Science & Applications (DOI: 10.37188/lam.2026.102), leverages both free-space and optical fiber echo signals. By detecting reflections from free space, it achieves 3D imaging with adjustable resolution from 0.3 cm to 1.2 cm at a distance of 30 meters. Concurrently, the system measures electrolyte density and temperature of a battery with accuracies of 3×10⁻⁵ g/mL and 0.5 °C, respectively. It also detects critical gases—C2H2, CO2, and CH4—with detection limits of 0.07 ppm, 48 ppm, and 0.56 ppm, which are essential for early warning of battery thermal runaway.
The innovation stems from integrating optical frequency domain reflectometry (OFDR) technology, which is typically used for fiber-optic sensing, into the LiDAR system. Both FMCW and OFDR use linearly modulated continuous light, but OFDR extends measurement capabilities to optical fibers, enabling distributed sensing of strain, temperature, and pressure. The scientists explain that by processing reflection peaks in the spatial domain, they can demodulate signals from fiber Bragg gratings, Fabry-Perot cavities, and multi-pass cells, allowing simultaneous measurement of multiple parameters.
In proof-of-concept experiments, the team imaged a plastic plate with the “HIT” symbol placed 30 meters away. They used sulfuric acid solution to represent battery electrolyte and measured its density and temperature, while a multi-pass cell containing a mixture of C2H2, CO2, and CH4 demonstrated gas concentration monitoring. This dual-functionality was achieved with a single demodulator, simplifying system architecture and reducing costs.
The potential applications are vast. In new energy vehicles, the system could combine imaging for autonomous driving with battery management, monitoring temperature, electrolyte density, and gas leaks to prevent thermal runaway. For spacecraft, it could provide both navigation and environmental monitoring. The researchers note that this technology could offer a new integrated solution to improve vehicle safety and reliability.
The development is timely, as electric vehicle adoption accelerates and safety concerns over battery fires intensify. Traditional FMCW LiDAR systems are limited to imaging, requiring separate sensors for environmental and battery monitoring, which increases complexity and cost. This multifunctional approach could streamline vehicle perception systems, making them more efficient and affordable.
Looking ahead, the team aims to refine the technology for commercial deployment, focusing on improving sensitivity and integrating it into existing vehicle platforms. The research was supported by the National Key Research and Development Program of China, the National Natural Science Foundation of China, and other national grants, underscoring its significance for future transportation and aerospace technologies.
