Electrified Connected Autonomous Vehicles (CAV) deployment has the potential to deliver major societal and environmental benefits. These advancements will be attained because of the improved energy conversion and optimized driving strategies of autonomous vehicles, and also by vehicle manufacturers using energy efficient components.
During the International Conference on Engines & Vehicles (ICE2021), Mircea Gradu, Velodyne Lidar’s SVP, Automotive Programs, and David Heeren, Velodyne Lidar’s Director Technology Research, presented in the “Energy Efficient Automated Vehicles” section. The session reviewed how selecting energy efficient lidar sensors can greatly influence the ability of electrified and automated vehicles to dramatically improve the overall environmental impact of the mobility ecosystem.
Electrified vehicles are far more efficient at converting consumed energy into power at the wheels than traditional gasoline vehicles. Electrified CAVs can deliver improved efficiency compared to human-driven vehicles by using data from Advanced Driver Assistance System (ADAS) capabilities to optimize operation. They present a huge opportunity to decrease the total emissions and environmental impact generated by vehicles on the road.
CAVs require lidar sensors to provide a full 360-degree field of view around the vehicle for navigation and collision avoidance. These sensors provide the perception data that enables a CAV to operate in all lighting conditions.
An electrified CAV’s energy efficiency is greatly dependent on the power consumption levels of its sensor suite and compute stack. The sensing, perception and decision making tasks of CAVs and the equipment needed to execute those tasks each have complex power requirements that impact energy usage.
Maximizing CAV efficiency by selecting low power components will be vital to increasing the environmental benefits of moving away from gasoline-powered, human-driven vehicles. These components will be critical for maximizing the travel range and uptime of EVs and hybrids.
The difference in power consumption between two potential lidar components in a CAV can have major consequences on a broad scale. For example, let’s look at the power consumption of two forward-facing lidar options: Velodyne’s Velarray, which typically consumes 15 W, and a sensor from a different directional lidar manufacturer, which typically consumes between 30-40 W, and up to 55 W.
This means the power consumption difference for a single sensor design can be up to 0.04 kW per vehicle and up to 0.16 kW different if a CAV utilizes four sensors for a surround view perception system. In 2015, Americans spent more than 84 billion hours driving, according to Federal Highway Administration data. If even only half of the vehicles in operation that year were equipped with a single sensor, using the lower power unit would have produced a savings of 1.68 trillion kWh, or 1.68 GWh. This amount of energy could power more than 150,000 average U.S. households for one year.
The power consumption of different lidar sensors can also affect EV range. New EVs typically consume between 24 and 50 kWh per 100 miles, or 0.24 to 0.50 kWh per mile. Using the other lidar manufacturer’s sensor rather than the Velarray would result in an additional 1/6 to 1/12 increase in the vehicle’s power consumption. That would decrease the vehicle’s range by approximately 8-to-16 percent.
In evaluating how sensor components impact CAV efficiency, there is a need to look at more than power consumption alone, such as reviewing the ratio of power consumption compared to other sensor performance specifications.
Power to performance ratios to consider include field of view (FOV)-to-power, range-to-power and resolution-to-power. They can provide insight into the relative amounts of power that are needed to achieve similar performance in key specifications.
As an example, let’s look at how Velodyne’s Velabit sensor compares to some competitive sensors on the market.
The selection of low power components needs to be seen alongside optimized driving behavior and improved power conversion efficiency as an influential contributor in the ability of electrified and automated vehicles to dramatically improve the environmental impact of the mobility ecosystem.
Blog post based on a presentation by Mircea Gradu, SVP Automotive Programs for Velodyne Lidar, at SAE International’s ICE2021, the 15th Annual International Conference on Engines and Vehicles Sept. 12-15, 2021.