Page 12 - EE Times Europe September 2021

12 EE|Times EUROPE

AV Complexity Explained

As AV regulations are introduced, safety and operational rules must The chart shows how various AV use cases fit into a two-
be included as part of the system and reliability design. dimensional space, with AV complexity increasing on the y-axis and
Also needed are hardware redundancy within the system design. At driving complexity growing on the x-axis. Driving complexity includes
least three AV systems require redundancy: driving controls (steer- route obstacles, driving speed, traffic density, road-user variety (cars,
ing, braking, speed), vision sensor capabilities (three categories), and bikes, pedestrians, etc.), and weather conditions. Fatality risks are
computing. also listed, mostly determined by speed. Some AV use cases have very
The system architecture must use technologies that can simplify low fatality risks.
software platform cooperation, allowing strong cybersecurity and OTA
updates. A recent column covered these topics (bit.ly/3A5wVbR). LOW AV COMPLEXITY
These systems remain quite expensive and will require significant Low AV complexity refers to simple routes, low speed, and low user or
cost reductions. Fortunately, chip-based technologies are providing traffic variety. At the simplest level, operation is restricted to closed
substantial cost savings, especially for the most expensive compo- areas such as a campus, office park, or military base. Sidewalk delivery
nent: LiDAR. vehicles are furthest along, with multiple players. Starship, the side-
Simulation of AV components is critical, including software and walk AV leader, surpassed 1.5 million deliveries in May 2021 and will
hardware as well as all types of testing and modeling. soon surpass 2 million deliveries.
AV event data recorders will be required to gain insights into crashes Fixed-route AVs also have low AV complexity, and the market niche
and what can be done to improve safety. Teleoperation is also becoming includes multiple players. Deployment has been slow because of high
standard in AV regulation and can be the key to limp-home capabilities AV prices, but fixed-route AVs have been undergoing testing in hun-
while solving edge cases. dreds of cities. Applications include low-complexity bus routes and/or
Problem No. 3 is developing a software-based driver that can drive closed environments.
better than a human, though how much better is still being debated. Fixed-route AVs are also likely to be used on flexible trips such as
It’s clear that AV developers must continue to test and improve their on-demand pickups. The ISO 22737 low-speed autonomous driving
systems. Development time will depend on the use cases. (LSAD) regulation, released in July 2021, should have positive impact
Edge case testing is used extensively and basically means find- on fixed-route AV deployment.
ing new driving situations that the software driver has not seen Goods-only AVs for last-mile deliveries bring with them more traffic
before and may not know how to handle. Adding new edge cases complexity, navigating roads at higher speeds than sidewalk AVs. Vans
to the software-based driver capability is considered perhaps the and small trucks can also be retrofitted as AV delivery vehicles. They
highest priority. are undergoing testing using safety drivers.
Another hard problem is confirming that AV software-based drivers
can outperform human drivers. It’s unclear how AV regulations and MEDIUM AV COMPLEXITY
future AV type approval will handle this important problem. This category includes several AV scenarios. Low-speed goods AVs
Solutions mostly involve testing, analysis of vast amounts of test without a safety driver are in this category. Autonomous trucks with
data to identify software driver weaknesses, and then more testing. hub-to-hub routes may also be included but, for now, require a safety
Fortunately, much of this testing can be
simulated at a much higher rate than road
testing — up to 100× more miles per day in
simulation mode versus road testing. Those
simulations are focused on edge cases and
similar scenarios.
Testing must include different weather
and lighting conditions. Most historical AV
testing has been done in ideal weather condi-
tions; hence, the need for greater real-world
simulations.

AV USE CASES
IMAGE: SHUTTERSTOCK considerably depending on the AV use case.
The complexities just described will vary
AV complexity is mostly decided by driving
complexity. The figure to the right is an
overview of AV use-case complexity, focused
on SAE L4 deployments. Many variations of
these scenarios are not included.

SEPTEMBER 2021 | www.eetimes.eu