Automated driving depends on scores of electronic systems for sensing, communication and control throughout the vehicle. Electronic systems throughout the vehicle control the motor, powertrain, steering and suspension, as well as operating the dashboard instrumentation, navigation, entertainment consoles and speakers, cabin and exterior lighting, heating, ventilation and air conditioning (HVAC), automatic seats, windows and mirrors. Advanced electronics save weight, improve operation, increase energy efficiency and make cars safer, more comfortable and convenient. They are also essential to the gradual introduction of autonomous driving, the change from combustion to electric propulsion and the ongoing improvements to the travel experience. Automakers will need to accommodate consumer expectations with the design of their products.
The driving forces
Automated driving and vehicle electrification are both multistage and multi-generational. To track developments in automated driving, SAE International created the J3016 standard to define five levels ranging from none at all (level 0) to fully self-driving (level 5), with different degrees of non-human control in between. Many features in the lower levels have already appeared in production vehicles, including dynamic stability control (level 1), adaptive cruise control and lane keeping (level 2), while limited self-driving for situations such as, automated parking or driver incapacitation in emergencies (level 3) is on the horizon.
Along with advanced information and warning features, these driving aids are collectively known as Advanced Driver Assistance Systems (ADAS) and they promote safety and convenience. The success of ADAS is extremely important to the automotive industry; according to Strategy Analytics, these systems will grow to an estimated market of more than $37 billion by 2021.
Informational ADAS, such as, rear-view or surround-view camera systems with displays, provide drivers with a better field of view and allow them to see into blind spots. Machine vision-based systems process information from a variety of sensors to identify objects and dangerous environments surrounding a vehicle, and warn the driver with visual, haptic or acoustic signals. ADAS takes it a step further and can perform simple manoeuvres for the driver, like steering the vehicle back into the centre of the lane or completely stopping the car if a pedestrian steps in front of it. For highly automated and fully automated systems in a vehicle (also called self-driving cars), many sensors and subsystems will have to work together to transmit, combine and process all available information (also called sensor fusion) in real-time. This can make decisions not only to affect steering, acceleration and braking, but also route planning.
Vehicle electrification has similar levels of limited to fully electric operation, giving consumers a selection as they become accustomed to the technology. Generally, the automotive industry distinguishes the EV categories listed in Table 1. Each category includes the features in those above it, and each, in turn, saves an increased amount of combustible fuel. Of those listed, mild hybrids and plug-in hybrids are predicted to be the fastest-growing categories in the next few years.
Vehicle electrification through these stages complements the development of automated driving because both depend on advanced electronics deployed throughout the vehicle. In some cases, both electric drive and automated driving may use the same systems for acceleration and stopping; in other cases, they may share sensing, computing and communication resources for operation and diagnostics.
A third major trend in automotive electronics is the ongoing development of greater comfort, convenience and connection to the world outside the vehicle, going back to the earliest installation of car radios. With increased freedom from the strains of driving, consumers will want their traveling experience to be more enjoyable in terms of climate control, sound, light, communications, and at-hand or voice-activated conveniences.
In general, these types of systems fall into two groups: those in the instrument cluster and dashboard that provide information and entertainment, and those in the car body and lighting that facilitate comfort and convenience.
ADAS paves the way to autonomous vehicles
Providing the pathway to vehicle automation, ADAS technology is based on extensive sensing and imaging from cameras, ultrasound, radar and LIDAR. The more ADAS technologies, the greater the need for high-bandwidth communications, high-performance image (and other signal) processing, and intelligent control. The information has to be processed immediately, so functional acceleration and low-latency communication is especially important, as is using as few wires as possible to save space and especially weight.
Cameras produce a vast amount of video data, requiring algorithms to filter and condition that data. These algorithms also search for and recognise objects of importance, such as, traffic lights, lane markings, pedestrians and other vehicles. All of this takes place in real-time, along with determining whether the car should swerve, slow, stop, etc, and initiating the action.
As more ADAS features appear, there will be a greater need to fuse the electronic functions – both to save space, weight, cost and functional resources – and to provide redundant sensing and imaging for greater reliability. For instance, a video camera trained on the road ahead has limited visibility at night or in fog, rain or a dust storm. However, augmented by other sensors, such as, radar and LIDAR, a ‘look-ahead’ system can compensate for the limitations of the camera.
Infotainment & cluster systems
Infotainment systems combine a variety of technologies in a central location to aid drivers and provide information and entertainment. Traditional instrument gauges are giving way to digital cluster displays with as-needed alerts and on-demand information in intuitive formats. For instance, ADAS functions may alert drivers that other vehicles or objects are in the roadway through an aerial display, while a head-up display (HUD) projected on the windshield keeps the driver’s eyes on the road.
Changes in infotainment systems connect the larger world to the vehicle. Emerging, integrated entertainment, multimedia and informational functions mimic the utility and familiarity of a smartphone. As the nerve centre of the car, infotainment and cluster systems require connection to the ADAS, powertrain and convenience systems. Flexibility is key to the processing solutions on which infotainment and cluster systems depend: flexible communications because data connections may vary, flexible configuration to support hardware differences among car models, and flexible software that permits adaptation to various trim lines and design cycles. With flexibility comes scalability, so that the same microprocessor family can support multiple vehicle types.
The long-term growth of electronic functions will come over time, helping reduce design times with proven development tools and software reuse. Additional needs include highly efficient power supplies to support low-power and multi-rail requirements, high-speed serial receivers for minimising communications wiring, sensors to monitor light dimming and cabin temperature, and a variety of other functions that promote comfort, convenience and safety.
Body electronics & complex lighting
The wide range of conveniences included in vehicle body electronics depend on miniaturised, cost-efficient sensors. Many positioning features, such as those that report an unclosed door or move a seat automatically, depend on position sensors that are integrated along with other circuitry. Touch-sensing buttons or panels, sometimes aided by haptic feedback, can replace spring-activated switches that wear out. Door locks and alarms operate with wireless switching, as well as being tripped by door positioning and seat pressure sensors.
Introductions in voice-activated controls that promote an interactive human-machine interface (HMI) are based on human voice recognition systems, working in tandem with processing of voice commands. Along with these and other sensors, are small motors, solenoids and other actuation devices driven by compact circuitry.
Adaptive lighting systems have generated some of the most exciting innovations in the automotive industry. Until the last decade, most headlights only had static, on/off functionalities and the majority were used incandescent bulbs. Now debuting in high-end vehicle models, adaptive headlight systems comprise of LED or Xenon headlights that dynamically adjust beam direction and intensity. An LED matrix manager enables adaptive headlight technology to provide better roadway illumination.
The electrification of powertrain subsystems
While the powertrain is all but invisible to drivers and passengers, it remains the most fundamental technology in the automobile. China, India and several countries in Europe, are planning to ban vehicles with internal combustion engines (ICE) between 2030 and 2050. Thus, the changeover of subsystems from ICEs to electric motors is progressing quickly. The industry demands innovative electronics solutions for the high-powered drive and fast charging needed for HEVs and EVs, for making fuel-powered engines operate more efficiently and reducing weight in areas such as power steering.
Power management, important in all electronic systems, is far more challenging under the hood than elsewhere in the car. Wildly differing voltage levels, ranging from 3 V to more than 800 V, may need to be supported, and electronic power supplies must accommodate the rise and drop in battery voltages caused by various charging and load conditions. Maximum voltages that surpass the capabilities of silicon require new compound power transistor materials. High voltages and associated high currents require ICs built with reinforced isolation techniques to protect circuitry and people from overloads and dangerous discharges.
Precise motor control is essential to powertrain electrical subsystems. A motor creates every electromechanical rotation, from low-power motions in compressors, fans and blowers to high-powered wheel propulsion in HEVs and EVs. DC motors in a vehicle have different power and control requirements, with the most demanding applications requiring robust sensing; high-performance signal-processing algorithms; and precise control of voltage inputs to achieve the desired outputs of torque, speed and position. Steady electrical operation also means that DC motors have to run for longer hours than they once did, creating new reliability issues. Powertrain technology suppliers need extensive expertise in sensing, power management and motor control to bring innovative solutions to automotive OEMs.
Technologies accelerating innovation
Across all sectors and market trends, the following six technologies are accelerating innovation in automotive systems: sensing & signal conditioning, embedded processing, connectivity, lighting & displays, power management, and isolation. The challenges facing the automotive industry require innovative electronics technology in power management and throughout the signal chain. Car manufacturers and tier-1 suppliers who need advanced semiconductor solutions also need wide-ranging technology and expertise from their suppliers, plus in-depth support to help them create and release new models.