Electronics At Your Service!
It is well known that the application of modern electronics in a car is not exactly a cost-saving factor, on the contrary. For a modern vehicle, the cost of electronics is estimated at one third of the total cost of production. Nevertheless, we note that its use continues to increase and that its applications are numerous. Initially, most electronic applications were at the level of engine management, transmission and fuel supply. Today, we notice that electronics is focusing more and more on driver assistance. Without wishing to be exhaustive in this area, we will try in this article to give you an overview of recent developments in automotive electronics.
Electronics is not a recent phenomenon.
The use of electronics in the car is not new. Some applications are already part of the standard equipment of each car. These standard applications are found mainly ‘under the hood’, the cradle of the first applications. Typical examples include engine and emissions management, automatic transmission and electronic fuel injection. The same conductive wire characterizes these first applications, namely to ensure optimal propulsion of the vehicle. Even today, this application continues to play a vital role. In the near future, most cars will be compulsorily equipped with an ‘On Board Diagnostics’ system which will ensure optimal operation and therefore minimal pollution of the vehicle. Over the years, however, electronics has been increasingly used to support other developments. Following the emancipation of the motorist, demanding an increasing level of comfort, security and protection, modern electronics has quickly found its way to applications in the field of air conditioning, comfort of seats advanced braking and stabilization, anti-theft devices (car-jacking), … These ‘new’ developments can roughly be divided into two areas of application: interactive and autonomous applications, the first group relating to applications involving an interaction (direct or not) of the driver. Autonomous systems, on the other hand, refer to ‘smarter’ applications, which no longer require driver intervention.
Just take the wheel of a modern car to realize that driving a vehicle nowadays is not easy. Today’s driver is in constant communication with his vehicle via a variety of alarms and audible signals. It is therefore in the cabin that we find the most interactive electronics. An overview. Air conditioning, for example, a system that was purely manual in origin, has evolved into a fully automatic, constant-temperature version that ultimately leads to a pro-active system that, through sensors, creates the car the ideal environment, given different parameters such as sunshine and the thermal condition of each passenger.
Considerable progress has also been made in terms of on-board navigation. By combining several technologies, we have succeeded in optimizing intelligent navigation. The interaction between GPS (global positioning by satellite) and RDS (radio data system) offered great possibilities. Indeed, the combined navigation system not only calculated the optimal route, but also actively anticipated new traffic conditions reported by the RDS system of the car radio. Another technological crossroads that will undoubtedly contribute to the realization of intelligent navigation, is the ICC or intelligent cruise control. Using radar technology, this cruise control ensures not only a constant speed but also ensures that a minimum distance from the vehicle ahead is maintained, depending on the speed of the vehicle (see Figure 1). Complementary interaction between the vehicle and static roadside sensors (which provide traffic and pavement condition information) should in the future increase the sophistication of intelligent and autonomous navigation.
Other applications still, that we can not detail under this article, already equip some cars:
Parking assistance by ultrasound;
Intelligent headlamp with variable light intensity according to the speed;
Intelligent rearview mirror with automatic adjustment according to the brightness and direction of the car;
Heads-up display with projection of the main measuring instruments on the windshield, night vision, etc.All of these applications, each with a screen and a control console, give the driver a glut of information. In addition, the space in the cockpit is relatively small. This is why manufacturers are making every effort to consolidate vital applications into a single control unit. A central unit that manages and coordinates the main interactive systems, so that the driver’s attention is distracted only to a minimum. This is also why these applications often use the latest voice-control technologies. Figure 1: Adaptive Cruise Control ACC
The second group of electronic applications comprises autonomous systems whose operation no longer requires intervention from the driver and do not send any more information to it. Most of these systems interact with the ‘dynamic behavior’ of the vehicle and its sometimes referred to as ‘electronic or intelligent chassis’.
The basic elements of the electronic chassis are the anti-lock system and the traction control system (ABS, TCS). These systems control the braking and acceleration movements too abrupt and therefore have the function of ensuring optimum adhesion of the tires on the road surface.
Figure 2: Electronic Stability Program (ESP)
With the arrival of the Electronic Stabilization Program (ESP), the electronic chassis has acquired an extra dimension. The ESP makes it possible to correct the lateral movements of the car, for example in case of under- or over-driving of the driver (see Figure 2). In ’emergency situations’, this system calculates the driver’s intention based in particular on the position of the brake pedal and the angle of rotation of the steering wheel. By acting on engine power and braking force, the ESP then tries to correct the behavior of the car by returning it to the desired driving pattern. The system uses an autonomous braking force, which means that the car decelerates without the driver having to operate the brake pedal. Ultimately, this system can be very interesting, as it can be combined with intelligent navigation systems.
Significant progress has been made in recent years in terms of passive safety, thanks to developments in the field of electronics. Notwithstanding all technological improvements, we have still not managed to prevent all accidents. On the other hand, it has become possible to limit the consequences that may result from an accident. In this respect, the airbag has been a pioneer. In recent years, the number of airbags in the car has not only increased (side airbags, face shields and foot guards are increasingly part of the standard equipment) but their operation has also been perfected. The current intelligent airbags control, before unfolding, what are the places occupied in the car, by whom (adult, child, baby) as well as the position in which these people are. On the basis of these data and those of the car (speed), the control unit will decide not to activate the airbags, to deploy them only partially, totally or in several phases.
Technically, it is already possible to take the necessary safety measures in the passenger compartment even before the impact. In fact, the ‘collision radar’ calculates a few milliseconds before impact the likely location and force of the collision and sends this information to the control unit of the seat belt pretensioners and airbags. This technique makes it possible to optimize the operation of the airbag. Here too, it is obvious that this system is likely to play an important role in the development of a car operating completely autonomously.
Under the hood
The increased use of electronics is causing a real ‘internal’ revolution. Without going into details, we can see that the exchange of data inside the electronic circuit has really exploded. The use of new materials and techniques with greater processing capacity, such as fiber optic cables and multiplexing, is still capturing this multiplicity of data. However, many engineers are looking for ‘wireless’ solutions to solve this capacity problem; drive-by-wire, brake-by-wire and steer-by-wire are therefore concepts that are emerging more and more. As the term suggests, these techniques use miniaturized transmitters based on a series of sensors integrated in the steering wheel, brake pedal and gas pedal, send signals to a hydraulic or pneumatic central unit that , in turn, generates the required brake, acceleration or steering pressure. The physical connection between the control unit and the controlled element is destined to disappear in the future. Because of this disengagement, these systems are therefore important elements for the development of the intelligent car, capable of driving alone.
As a conclusion
In conclusion, it should be noted that, although very fascinating, these systems will never replace the driver. In principle they remain auxiliaries or correctors of conduct. The driver must therefore avoid the false sense of security generated by these systems. He alone and remains responsible for his own way of driving. When the first intelligent and autonomous car will conquer the market, we can only answer this: the necessary technologies already exist. The important question seems to us rather to know if the man is himself ready to be led and if the authorities are ready to invest in telematic solutions?Tags: electronics