Connected Cars and Self-Driving Cars: SAE Automation Levels & V2X Technology Explained
In the ever-evolving landscape of the automotive industry, four interconnected megatrends are reshaping the way we think about vehicles: vehicle electrification, self-driving cars, vehicle connectivity, and shared mobility. As we hurtle into the future, the race to achieve seamless vehicle connectivity and full automation is on, pushing the boundaries of what was once science fiction. In this article, we’ll break down how connected cars and self-driving cars actually work, what the SAE automation levels mean, and the engineering challenges automakers are racing to solve.
In the fast-evolving landscape of the automotive industry, four megatrends have emerged as transformative forces: vehicle electrification, self-driving cars, connected cars, and the surge in shared mobility. These trends are reshaping the way we think about transportation, challenging traditional notions and paving the way for a more connected and efficient future.
Megatrend 1: Vehicle Electrification
The automotive industry is undergoing a profound transformation, with a shift toward cleaner and more sustainable transportation. Vehicle electrification has become a megatrend, driven by the urgent need to reduce carbon emissions and mitigate the environmental impact of traditional ICE vehicles. Electric vehicles (EVs) have emerged as the pioneers of this revolution, offering a cleaner, greener alternative to their fossil fuel counterparts.
The adoption of EVs is not just a matter of replacing engines; it involves a fundamental redesign of the vehicle’s architecture, integrating advanced battery technologies, electric drivetrains, and sophisticated energy management systems. As automakers strive to electrify their fleets, the race is on to develop more efficient batteries, extend range capabilities, and create a charging infrastructure that can support the growing demand for EVs.
Megatrend 2: Self-Driving Cars
Parallel to the electrification trend is the relentless pursuit of autonomous vehicles (AVs) — cars that can navigate and make decisions without human intervention. AVs promise a future where transportation is safer, more efficient, and accessible to all. The Society of Automotive Engineers (SAE) has defined levels of vehicle automation from Level 0 (no automation) to Level 5 (full automation). Understanding these levels is crucial to understanding the progression toward fully autonomous vehicles — we break them down in detail below.
Megatrend 3: Connected Cars
Connected cars, equipped with advanced communication technologies, have become the linchpin of the automotive revolution. These vehicles are not just means of transportation; they are intelligent, data-driven platforms that enable seamless communication between vehicles, infrastructure, and the broader transportation ecosystem. This connectivity is unlocking a myriad of possibilities, from enhanced safety features to personalized in-car experiences.
One of the biggest impacts of connected cars is in the realm of safety. Vehicle-to-vehicle (V2V) communication allows cars to exchange real-time information, enabling features like collision avoidance systems and cooperative adaptive cruise control. This interconnectedness has the potential to significantly reduce accidents and make our roads safer for everyone.
The traditional model of individual car ownership is facing a formidable challenger as more people opt for shared transportation options. Services like ride-sharing, car-sharing, and micro-mobility are gaining popularity, driven by the desire for cost-effectiveness, convenience, and a reduced environmental footprint.
Shared mobility is fostering a shift from a car-centric to a service-centric model. Instead of owning a vehicle, consumers are increasingly relying on on-demand transportation services. The shift not only aligns with the principles of sustainability but also addresses issues of urban congestion and parking challenges, transforming transportation into a service accessible to all.
What Is a Self-Driving Car?
A self-driving car, also called an autonomous vehicle (AV) or driverless vehicle, is a car, truck, or other type of vehicle capable of navigating and operating without human intervention. These vehicles use a combination of advanced sensors, cameras, radar, LiDAR, and artificial intelligence (AI) algorithms to perceive their surroundings, make decisions, and execute actions such as steering, accelerating, and braking.
Self-driving cars have the potential to reduce the risk of accidents by eliminating the element of human error from driving. However, these benefits come with rising energy costs — power demands from AV electrical/electronic (E/E) systems can reduce vehicle range by over 11.5%.
It’s important to note that, regardless of what any automaker calls its advanced driver assistance system (ADAS), there are no truly full self-driving vehicles on the road today. Misleading marketing from some companies has sparked real controversy over whether current AV technology is actually ethical and whether the world is ready for it — questions we explore in more depth in our guide to autonomous vehicle ethics.
Are Self-Driving Cars Available Today?
Today, there are no Level 5 autonomous vehicles on the road. However, certain SAE Level 4 highly automated vehicles are operating in several cities, including San Francisco, Phoenix, Los Angeles, Austin, Hamburg, and Beijing. These vehicles still have to operate within a geofenced area, and are currently deployed by companies like Waymo, Zoox, and Cruise.
SAE Levels of Vehicle Automation
Autonomous vehicles are categorized into six levels of automation, as defined by the Society of Automotive Engineers (SAE), ranging from no automation at Level 0 to full automation at Level 5:
- Level 0 — No Automation: The human driver performs all driving tasks, even with active safety warnings or momentary intervention.
- Level 1 — Driver Assistance: The vehicle can control either steering or speed under certain conditions, such as adaptive cruise control or lane-keeping assist, but not both at once.
- Level 2 — Partial Automation: The vehicle can control both steering and speed simultaneously (e.g., highway driving assist), but the driver must stay fully engaged and monitor the environment at all times.
- Level 3 — Conditional Automation: The vehicle can manage most aspects of driving in specific conditions, and the driver can disengage from monitoring the road, but must be ready to take control when prompted.
- Level 4 — High Automation: The vehicle can handle all driving tasks within a defined operational area (a geofenced zone), without requiring driver intervention, even if the driver doesn’t respond to a request to take over.
- Level 5 — Full Automation: The vehicle can operate under all conditions a human driver could manage, with no restriction on location or environment, and requires no human driver at all.
What Level Is Tesla Full Self-Driving?
Tesla’s Full Self-Driving (FSD) is the company’s branding for its beta testing program aimed at achieving full autonomy (SAE Level 5). The branding has sparked controversy, however, because vehicles in the FSD program currently operate at Level 2 automation, meaning they are not truly “fully self-driving” and require active supervision by the driver.
What Is a Connected Car?
Connected cars are at the heart of the automotive revolution, serving as the linchpin between electrification and autonomy. Connected vehicle technologies aim to tackle challenges in the areas of safety, mobility, and the environment.
A connected car is equipped with advanced communication technologies that allow it to interact with other vehicles, infrastructure, and external systems. This connectivity forms the backbone for the seamless integration of various automotive technologies, creating an intelligent and responsive ecosystem — a capability that, like the by-wire control systems covered in our X-by-wire systems guide, depends on reliable electronic control throughout the vehicle.
Types of Vehicle Connectivity: V2V, V2I, V2P, and V2N
“Connected car” technology is often summarized under the umbrella term V2X (vehicle-to-everything), which breaks down into several more specific communication types:
- V2V (vehicle-to-vehicle): cars exchange speed, position, and braking data directly with nearby vehicles to help prevent collisions.
- V2I (vehicle-to-infrastructure): vehicles communicate with traffic signals, road signs, and other infrastructure to improve traffic flow and safety.
- V2P (vehicle-to-pedestrian): vehicles detect and communicate with pedestrians’ and cyclists’ connected devices to reduce the risk of collisions.
- V2N (vehicle-to-network): vehicles connect to cloud and cellular networks for real-time traffic data, software updates, and remote diagnostics.
Benefits of Connected Vehicle Technologies
Connected and automated vehicle (CAV) technologies provide safety, comfort, and mobility enhancements. CAV technology also has a positive impact on energy consumption.
- Enhanced Safety: Connected vehicles can communicate with each other to prevent accidents and improve road safety. Features like collision avoidance systems and cooperative adaptive cruise control rely on vehicle-to-vehicle (V2V) communication.
- Traffic Management: With real-time data exchange, connected vehicles contribute to efficient traffic management. This includes dynamic rerouting to avoid congestion, optimizing traffic flow, and reducing overall travel time.
- Predictive Maintenance: Connected vehicles enable continuous monitoring of their components. This allows for predictive maintenance, reducing downtime and extending the lifespan of vehicle systems.
- Infotainment and Comfort: Connectivity enhances the in-car experience, providing passengers with advanced infotainment options, personalized settings, and the ability to seamlessly integrate with smart devices.
Cybersecurity and Privacy Considerations for Connected Cars
Every benefit of a connected car depends on constant data exchange, which also makes it a target. A vehicle broadcasting its position, speed, and diagnostic data over V2X networks needs to authenticate that data and protect it from tampering, since a spoofed or intercepted message could trigger a false collision warning or worse. Automakers address this with encrypted communication protocols, secure over-the-air update systems, and intrusion-detection software built into the vehicle’s electronic architecture. On the privacy side, connected vehicles also collect substantial location and driving-behavior data, which raises real questions about who can access it and how it’s used — a consideration that, alongside the ethical questions around autonomy itself, is part of a broader conversation covered in our guide to autonomous vehicle ethics.
Energy Savings via CAV Technologies: The ARPA-E NEXTCAR Program
The quest for energy efficiency has led to groundbreaking research and development initiatives. The ARPA-E (Advanced Research Projects Agency-Energy) NEXTCAR program focuses on developing technologies that optimize energy usage in connected and automated vehicles (CAVs) by integrating connectivity, automation, and advanced control systems. Greater energy savings can be achieved by pairing powertrain optimization with V2X information, and the program aims to increase vehicle energy efficiency by up to 20% through these combined technologies.
Connected and self-driving technology doesn’t exist in isolation — it’s layered on top of the same vehicle systems covered throughout this site. For a broader look at how these systems interact with the rest of the vehicle, see our vehicle systems overview, or start from our automotive engineering overview for the full picture of how a modern car is engineered.
Frequently Asked Questions About Connected and Self-Driving Cars
What is the difference between a connected car and a self-driving car?
A connected car communicates with other vehicles, infrastructure, and networks (V2X) but doesn’t necessarily drive itself. A self-driving car uses sensors and AI to control steering, acceleration, and braking without human input. The two technologies are complementary — many of the safety and efficiency benefits of autonomous vehicles depend on connectivity.
Are there any Level 5 self-driving cars on the road today?
No. As of today, no commercially available vehicle has achieved SAE Level 5 full automation. The most advanced vehicles on public roads, such as Waymo’s robotaxis, operate at Level 4 within geofenced areas.
Is Tesla Full Self-Driving actually fully autonomous?
No. Despite the name, Tesla’s Full Self-Driving (FSD) currently operates at SAE Level 2 automation, which requires the driver to stay attentive and ready to take control at all times.
What is V2X technology?
V2X (vehicle-to-everything) is an umbrella term for the communication technologies that let a connected car exchange data with other vehicles (V2V), infrastructure (V2I), pedestrians (V2P), and networks (V2N) to improve safety and traffic efficiency.
How much energy can connected and automated vehicle technology save?
Research from the ARPA-E NEXTCAR program shows that pairing V2X connectivity with powertrain optimization can improve vehicle energy efficiency by up to 20%.
Key Takeaways
The race to achieve vehicle connectivity and full automation is not just a technological sprint but a marathon that involves reshaping the very foundation of transportation. As we witness the convergence of electrification and autonomy, the automotive industry is poised for a paradigm shift that will redefine the way we interact with and perceive vehicles.
The benefits are far-reaching — from cleaner air and reduced carbon footprints to safer roads and enhanced travel experiences. The challenges are equally real, requiring collaborative efforts from automakers, technology companies, and policymakers, and careful engineering across every vehicle system touched by connectivity and automation. For a deeper look at how these systems come together, see our vehicle systems overview and automotive engineering guide.
Discover more from Engineering Cheat Sheet
Subscribe to get the latest posts sent to your email.
