Optical Coherence Tomography is a technology developed in the 90’s which can be found in the offices of eye doctors. However, engineers believe it may hold the key to improving the “vision” of self-driving technology and other autonomous systems (ScienceDaily).
Light Detection and Ranging, or LiDAR for short, is a system that works similarly to radar, except it uses lasers and light instead of soundwaves to determine the positions of objects. Many engineers are incorporating LiDAR into their driverless systems and robotics, but the technology is not without its drawbacks and limitations. One such drawback is that it is prone to picking up interference. LiDAR depends on being able to detect weak reflected light signals, and other light sources such as sunlight and other LiDAR systems can interfere with the system and cause the detector to become overwhelmed. It is also limited in its ability to scan large areas and may take a long time to fully scan a highway where split-second sensing is a necessity for safety (ScienceDaily).
A new form of LiDAR, however, is slowly taking the robotics and driverless car industry by storm. Frequency-modulated continuous wave LiDAR, or FMCW LiDAR, sends out a laser which is constantly changing frequencies, allowing the detector to distinguish it from other light sources via the specific frequency pattern. Interestingly, FMCW LiDAR uses the same working principle as Optical Coherence Tomography, or OCT. OCT sends light waves into objects and measures how much the light’s phase has shifted in order to determine how much time it takes for the light to reflect back (ScienceDaily).
With only a few tweaks, the technology, which is used by ophthalmologists to take cross-section pictures of a retina (AAO), can be used on a larger scale, optimizing the technology for use in driverless vehicles and other automated technologies. It is able to work in different lighting conditions, which would be impossible for a normal LiDAR system to accomplish, and it is able to process data much faster. The system is accurate and fast enough to capture the detailed movement of the human body like the clenching of a fist in real-time (ScienceDaily).
The technology will help robots and automated systems reach a practical level of object detection so that they can safely carry out their functions. Engineers hope that FMCW LiDAR-based three-dimensional cameras will become more and more prevalent in the world of automated technology over the coming years as more research is carried out (ScienceDaily).
Written by: Matthew Jenkins
Date: May 9th, 2022
Sources:
https://www.sciencedaily.com/releases/2022/03/220329114712.htm
https://www.aao.org/eye-health/treatments/what-is-optical-coherence-tomography
