New technological developments enable LiDAR in self-driving cars

By Aalyia Shaukat, contributing writer

 

Autonomous
vehicles are a potentially life-saving technology, and if perfected, could
drastically reduce the number of fatalities caused by operator error. The
technology these cars use to measure and interpret the world around them
function in a variety of ways. Current autonomous vehicles rely mostly on an
established technology known as LiDAR or light detection and ranging.

 

Car
accidents cause 1.3 million fatalities every year worldwide, and according to
U.S. regulatory statistics, 94 percent of them are solely attributed to human
error. Between the years of 2014 and 2016, the number of automotive fatalities
rose by a staggering 14 percent in the U.S., a rise which some analysts believe
corresponds to increased cell phone use and distracted driving.

 

LiDAR
functions similarly to its preceding RADAR and SONAR implementations by using
lasers, but LiDAR sends out high frequency pulses of light at wavelengths of
about 830 nm to 940 nm and uses a mirror instead of an antenna to scan the
laser. This light bounces back to a sensor, which interprets the signal and
calculates the distance the light has traveled by measuring its diffusion. In
this way, LiDAR systems enable autonomous vehicles to detect obstacles or other
vehicles.

 

LiDAR
technology is expected to advance rapidly over the next few years. According to
Yole Developpement the market for automotive LiDAR systems is expected to grow from
$726 million in 2017 to an astounding $5 billion in 2023. This boom in the
industry is being driven by a multitude of companies including Mitsubishi,
Nissan, Toyota, and Denso. According to a report from Knowmade in January 2017,
more than 30,000 inventions related to
LiDAR had already been published.

 

LiDAR,
however popular, is not the only autonomous vehicle guidance system in
development at this time. A multitude of other technologies are being developed
to augment LiDAR in the future. One such emerging technology is microelectromechanical
system (MEMS) scanners. These MEMS mirrors are built on the foundation of
previous LiDAR scanners but with a few advantages.

 

The
new MEMS scanners are both smaller and cheaper than previous LiDAR and use only
a fraction of the energy. They are also more accurate, using two lasers which
scan on separate axis and reflect onto a mirror rather than using one wide
laser. By using two axes, the MEMS systems can detect tiny movements faster
than previous LiDAR and could give autonomous vehicles a faster reaction time.

 

Other
companies such as XenomatiX and Continental propose a new kind of Flash LiDAR
in which the entire area is illuminated at once rather than being scanned,
reducing moving parts and driving down production costs. Other companies are
attempting to advance LiDAR by increasing the power of the laser from 830 nm to
the much more powerful 1550 nm―a feature that could provide better dust
resistance and more accurate readings in unpredictable conditions such as
rainstorms.

 

While
pulsed-based direct LiDAR is advancing rapidly, other technologies have been
created that function on a completely different principle. Continuous-wave
ranging methods are being developed to allow for heterodyne detection; a process which detects tiny phase shifts in infrared light
caused by motion. The phase shift ranging method is being developed by
companies IFM and Beneweke, while other companies like Oryx and Blackmore are
exploring the frequency-modulated continuous wave (FMCW) ranging method.

 

The
developers of autonomous vehicles in the future will have a smorgasbord of
options to choose from. “The IP landscape is dominated by Tier1s, and
automotive OEMs players that have contributed to the development of LiDAR for
ADAS applications (parking assistance, anti-collision alarms, etc.),” explained
Dr. Paul Leclaire, IP analyst at Knowmade. “Among the top 5 patent assignees,
four are Japanese including Denso, Mitsubishi, Nissan and Toyota. Main Japanese
players are automotive manufacturers.”

 

By
using LiDAR with new modulation techniques and new hardware such as MEMS
scanners, these new technologies could be used together to create safer and
much more reliable autonomous vehicles for the future. We can expect to see a
variety of these features coming into play in the years to come as developers
continue to research and apply these technologies to the automotive industry.

 

With
the growing demand for self-driving vehicles and many of these systems already
deployed, this technology will likely proliferate. The future of travel will be
automated and leveraging multiple technologies from millimeter-wave radar to
LiDAR; the redundancies designed in these systems allows for a much safer
travelling environment.