Group of cars being driven on the Olympic Games site in Munich: Z1, E1, Z13, Just 4-2. Advertising film from the 1980s: combination of actual shots of car and driver with computer-generated backgrounds Z1 assembly at the BMW plant in Munich Driving shots in Upper Bavaria,, red car, summer.

Studio shots, exterior design, red car Interior design, details Exterior details (E1 badge etc.), shot in helicopter hangar, red car View under the front hood Charging plug pulled out of socket and stowed away behind E1‘s front grille. Starting, battery function and charge indicators in the car computer E1 is driven out of helicopter hangar Driving shots in a small Bavarian town, red car

Scene: driver of Z13 collects business associates from Munich airport, loads their luggage, everyone gets in and car is driven away. Blue car Driving shots in Munich city traffic and on country roads, blue car. Interior: studio shots Design, exterior: studio shots, blue car.

Design: details, 2 cars, shot in front of the BMW Technik premises Driver gets in, fastens seat belt, puts on helmet and drives off Driving shots in Munich (Olympic Games site, Middle Ring), blue car

BMW Technik building in Munich, BMW pylon in front Reception/foyer: visitor approaches counter Reception/foyer: employees of BMW Technik GmbH meet for an informal discussion at bistro tables. In the background, two ‘Just 4-2’ vehicles on display.

Engineers and technicians at work, discussing experimental steer-by-wire vehicles Design studio: interior designers discuss colour and material for a new steering wheel Interior designer producing a draft sketch Designer (woman) cutting out cloth for seat upholstery.

Just 4-2, blue, in the BMW Technik acoustic wind tunnel Just 4-2 is prepared for a wind-tunnel test Just 4-2 in wind tunnel: aerodynamic tests (some with smoke trails to make the airflow visible) Control panel of acoustic wind tunnel with Just 4-2 in background (visible through window) Just 4-2 in wind tunnel: experiments with driver on board Clip-style film sequence, cut to music: members of the Austrian national skiing team training in the acoustic wind tunnel and optimising their clothing and their crouched position at speed. Inter-cut with shots of downhill ski races.

Q: This year BMW Technik GmbH is celebrating its 15th anniversary. What is the basic concept that led to the company being formed? A: BMW Technik GmbH was established to act as an independent development company. We regard ourselves as trend scouts or as a think tank for new technical developments on the automotive scene. The idea behind this is that as a small corporate unit we can be very flexible and put new technical concepts into effect quickly, including unconventional ones that are often slowed down by the sheer size of major corporations. In this way we can come up with new and attractive ideas which BMW AG can consider adopting. Q: What is the status of BMW Technik GmbH today within the BMW Group, and how is it integrated into the Group as a whole? A: BMW Technik GmbH is linked organisationally to the member of the BMW AG Board of Management with responsibility for development work. Our aim is to create near-series products that could be manufactured in volume later, but are none the less notable for the new technologies they incorporate. As a result of this link, there is a continuous exchange of information with the specialist departments at BMW AG, so that we can be certain of our ideas being considered for subsequent use in that company’s production models. There is a further aspect which I would also like to mention. We also regard ourselves as a suitable training ground for qualified young engineers who can learn the full range of activities associated with complete motor vehicles from us and therefore invite consideration for highly skilled tasks at BMW AG subsequently. Q: What precisely are the work areas that your engineers deal with here, and which areas of vehicle development do you handle? A: Under one roof we have all the functions needed to develop complete vehicles and build prototypes. Our lean structure and the absence of a complex hierarchy naturally makes us exceptionally efficient in the processing of such projects; this can be seen from the fact that we seldom need more than a year before the vehicle first turns a wheel. Q: What technical facilities do you have at your disposal? Is your facility just a smaller replica of BMW’s Research and Engineering Center, or does BMW Technik have certain technological facilities of its own? A: We naturally have all the facilities needed to develop and build a vehicle, and of course a design and styling studio as well. There are design departments, simulation tools and a prototype construction shop in which we can build the actual vehicles. There is an electronics laboratory too, which as you can imagine has become more and more important in recent years as electronics take over more and more functions on motor vehicles. We also operate two engine test dynamometers, and there is one facility that I want to mention particularly: our wind tunnel. This is an acoustic wind tunnel, incidentally the first to go into operation anywhere, fifteen years ago. We are still ‘state of the art’ with this wind tunnel, and it gives us a great many advantages when developing prototypes, because we can study the acoustic and aero-acoustic properties right from the start. Let me digress for a moment: twice ya year the Austrian national skiing team visits us to practise the ideal crouched position for their downhill races. Far be it from me to suggest that we have made the Austrians so successful – but we can clearly claim to have played a small part in their many victories! Q: What form doe

BMW Technik’s prototype workshop: building the second Z22 (P2) prototype. Fully-equipped Z22 functional buck made from aluminum, with axles, wheels and engine (at rear), crash element (at front) etc. Various tracking shots Occupant cell made from composite fiber material (CFK) is mounted on the Z22 frame (the ‘marriage’) and aligned Attaching the front hood (concealing the crash element) Installing the seats Installing the steering ‘wheel’ Prototype with occupant cell installed Offset frontal crash (40 % overlap): Z22 (P2) impacts a deformable barrier at 64 km/h (NCAP test). High-speed camera shots Z22 vibration simulation: occupant cell located at vibration nodes on structure of prototype (shown in green) to reduce transmission of vibration

Parallel runs with Z22 (1st prototype) at BMW proving ground near Munich Tight slalom course: Z22 is driven in a highly dynamic manner round pylons (steer-by-wire clearly reduces driver’s steering effort) Interior/controls: Fingerprint – driver’s door opens when fingerprint is identified, engine starts after a further check on the fingerprint and when driving switch (automatic selector switch) is turned On-board monitor (and a wide variety of car functions) operated by rotary/pressbutton control on center console (or from multifunctional steering wheel) Various function displays on the monitor (navigation, audio, driving functions, computer, air conditioning etc.) Center console, multifunctional steering wheel Mirror replacement system: instead of the conventional mirror a monitor shows everything that is happening behind the vehicle. The monitor picture is combined from three cameras in the Z22’s tail and doors, and supplies the driver with the same information as three separate mirrors

Q: BMW Technik GmbH has built the Z22 as a means of demonstrating advanced technologies. How many technological innovations does it contain? A: Our Z22 is an advanced technology demonstrator that incorporates about 70 innovations. These have in turn led to 61 inventions being registered with the authorities. In other words, the emphasis is on advanced technology and the Z22 is not merely a design study.Q: You have announced the Z22 as the ‘lightest and most advanced mechatronic car in the world’. What lies behind the term ‘mechatronic’? A: The Z22 is the first prototype to be revealed with such an exceptional number of innovations related to every aspect of driving. Mechatronics place a particularly important part in this: the word is the general term used for mechanical systems under electronic control. Q: Is the mechatronic car the car of the future, and what areas of the Z22 feature mechatronics? A: In the next few years mechatronics, lightweight construction and new methods of control will revolutionise automobile design. Among the key technologies for mechatronics are ‘steer by wire’ and ‘brake by wire’. On the Z22 they have completely taken over from mechanical steering and the hydraulic brake system.Q: What are your aims with the Z22 in terms of weight-saving? Which weight-saving technologies and which body concept are used for this advanced-technology vehicle? A: The main objective with the Z22 is to combine driving pleasure with the satisfaction of saving money. To make this possible and to fulfil the project’s other objectives, the car has to weigh less than 1,100 kilograms, in other words the weight of a modern small car. We therefore gave top priority to developing lightweight parts in every area of the car’s design. Its suspension and body concepts are both 50 percent lighter than if conventional methods and materials had been used. The body concept, for instance, divides the vehicle horizontally into a functional frame and an occupant cell; the former uses aluminium for the functional elements, the latter is made from a high-performance composite material. By mounting the cell at the nodal points of the functional frame, we can also reduce the noise transmitted through the structure to a very low level. Q: Is the Z22 merely a kind of mock-up or can it actually be driven on the road? A: The Z22 is a fully functional test vehicle that has already covered many thousands of kilometers. Before this P1 prototype, three experimental vehicles were built and used to investigate certain of the main topics and other fundamental design areas. We also built a further prototype for crash testing, which passed the various tests with great success.Q: What project or other objectives are you pursuing with the Z22? A: The specific tasks were to build a typical BMW but one that uses 40 percent less fuel. Some of the other development targets it has achieved are the same drive-off acceleration and flexibility as a conventional midsize car, the same overall length as a small car but with a midsize car’s interior space, at 1,100 kilograms the weight of a small car, but no shortcomings in comfort and refinement. On the contrary, we have solved the conflict of objectives between lightweight construction, refinement and crash performance. The new materials we have adopted and the new construction methods and technologies will be available gradually from 2005 onwards for a production rate of at least 100 cars a day that will set genuinely new stand

2D animation: Steer-by-wire (SbW) systems have no mechanical link between the steering wheel and the car’s front wheels. The driver turns the steering wheel (1) to indicate the desired direction. The amount of movement is measured by the steering angle sensor (2) and transmitted to the control unit (4). The control unit uses the steering angle signal and other influencing factors such as road speed, lateral acceleration, yaw rate etc. to determine what angle is needed at the road wheels. Two front-wheel steering motors (5) move the rack (7) and turn the front wheels (8). A wheel moment sensor (6) measures the forces acting on the wheel and transmits this value to a feedback motor (3), which is used for a realistic simulation of the feedback from the road that the driver feels at the steering wheel. The steering and feedback ratios can be varied, for example so that the steering is more direct when parking and manoeuvring, with lower apparent effort at the wheel, but less direct at high speeds so that the same excellent road behaviour is obtained as on current production models. Steer-by-wire systems can even include automatic correction, for instance to keep the vehicle stable when driving close to the dynamic limits or when exposed to severe cross-winds. Driving shots on the BMW proving ground near Munich. Comparison between a series-production car (3 Series touring, dark blue metallic, standard steering wheel) and an experimental car from BMW Technik with steer-by-wire (3 Series touring, light blue metallic, experimental steering wheel). On the car with SbW, the effort needed at the steering wheel, particularly at slow speeds (e.g. when parking or turning round in the road) is definitely lower than on the production car, for greater comfort and convenience, and this is also true in a series of fast bends (e.g. slalom course), when the car feels more agile and responsive to the steering. On the handling course On the slalom course U-turn (180 degrees) with SbW – hands don’t need to be repositioned on steering wheel Reverse turn with SbW – hands don’t need to be repositioned on steering wheel.

Q: Can you explain in brief exactly what steer—by-wire means? A: ‘Steer-by-wire’ or SbW is an electro-mechanical steering system that replaces the mechanical link between the steering wheel and the front wheels by an electrical connection.Q: How does steer-by-wire work? A: Like this: a sensor on the steering wheel measures the amount by which the driver turns the steering wheel and transmits this as a signal to the control unit. This turns the front wheels by means of two electric motors. The feedback force at the road wheels, which is important as a means of giving the driver a sense of control over the vehicle, is measured and transmitted back to the steering wheel. Q: What advantages does steer-by-wire have compared with a conventional steering system? A: The advantages of ‘steer by wire’ over mechanical steering systems are concentrated into two areas. First of all the steering ratio can be made dependent on the vehicle’s speed, which solves the conflict of objectives between minimum effort when parking, agile handling on ordinary main roads and stability at high speeds. In addition, the car’s safety can be enhanced, for instance by active regulating systems that compensate for cross winds, and by eliminating the mechanial steering column, so that occupant safety is improved.Q: Since the steering wheel doesn’t have to be turned by the usual amount, steer-by-wire enables the driver to keep his hands in the same position on the wheel in most situations. But is the typical feeling of driving a BMW still there? A: By varying the steering ratio according to road speed, we can make it possible for the driver to handle any situation without moving his or her hands to a new position on the steering wheel. For example, the car can be parked without turning the wheel by more than 160 degrees. Another example is that the car is much more agile on typical country roads with a succession of corners, since the steering wheel has to be turned to must less extreme angles than in a conventional car. On the motorway or “autobahn”, however, it is just as stable as a production car today. The BMW feeling that is so typical of the way our cars handle and steer is still there in full, in every driving situation. Q: Does SbW mean that the driver has to change his technique radically? A: The driver will get accustomed to ‘steer by wire’ with very little change in his or her driving technique. Although the steering wheel angles are much smaller, this is something that one gets used to very quickly.Q: What about the safety of a car equipped with SbW? A: As you can imagine, we give top priority to safety in our development work. This is what’s known as a redundant system, that is to say, each sensor, control unit and motor is duplicated at least once, so that if one of them should fail the other components take over its task immediately. Q: When did you start the steer-by-wire project, and how long will it take to reach series production? A: BMW Technik began its ‘steer by wire’ work in 1995, at the same time as the Z22 project. It will take some time before these systems can be adopted on production cars, because at the moment the authorities don’t approve them, although work on suitable legislation is in progress.

2D animation – variable steering ratio (picture: German version) Active Front Steering (AFS) is a ‘by wire’ system that retains the mechanical link betweent he steering wheel and the front wheels. It is a combination of controlled power assistance and a superimposed steering action. Th system supports the driver’s own actions in all driving situations when the steering has to be turned. This makes the task of steering much more agreeable for the driver due to the increased comfort and agility it provides. Furthermore, in difficult dynamic situations the driver is supported by the system turning the wheels actively, without any action on the driver’s part. The basic principle is similar to a conventional steering system: the driver turns steering wheel (1) and the effort is transmitted mechanically via the steering column to the steering box (6), which moves the road wheels (8) accordingly. At high speeds the equivalent ratios for AFS and conventional steering are about the same. At low speeds, on the other hand, for instance when manoeuvring the car, AFS assists the driver by making the steering ratio more direct. It does this by using a sensor (2) to measure the steering angle and transmit a corresponding signal to a control unit (3). The control unit energises an electric motor (4) which turns a gear train (5) in the steering column and thus generates an additional steering angle (4 + 5 = actuator) which has the effect of greatly reducing the steering effort. This additional steering angle can also be built up when changing lanes rapidly, for example. This causes the car to respond in a more immediate and agile manner to the driver’s steering commands. A servo motor (7) in the steering box generates the steering-wheel moment corresponding to the overall driving situation, so that the driver always senses the correct amount of feedback at the steering wheel. 2D animation: stabilizing function (picture: German version) In the example shown here, the car is being driven in a straight line. An external influence (10) such as a cross-wind or a difference in the amount of friction under the right and left wheels makes a steering correction necessary. As soon as the sensors (9) register this situation, AFS begins to take effect. By means of the steering angle sensor (2) it detects the driver’s directional instructions (in this case straight ahead) and uses the components described above to eliminate the effect of the disturbance. In other words, it corrects the road wheel angle slightly – just enough to keep the vehicle dynamically stable. AFS can also exert a stabilizing effect if the car tends to over- or understeer when cornering. In critical situations, AFS is supported by the intervention of the DSC brake regulating system.2D animation – variable steering ratio (Picture: English version) 2D animation: stabilizing function (Picture: English version) Driving shots on the BMW proving ground near Munich. 5 Series sedan/saloon as experimental vehicle, on which AFS can be switched on and off. With it switched off, the car reacts like a series production car. “Exterior” = car filmed from outside; “Interior” view over driver’s shoulder or close-up of steering wheel Avoiding action, exterior, AFS off Avoiding action, exterior, AFS on Avoiding action, exterior, AFS off Avoiding action, exterior, AFS on Avoiding action, interior, AFS off Avoiding action, interior, AFS on Avoiding action, interior, AFS off Avoiding action, interior, AFS on Avoiding

Q: What does AFS mean? A: AFS is the abbreviation for ‘active front steering’, a system that is capable of moving the front wheels independently of the driver’s actions at the steering wheel.Q: How does AFS work? A: Active Front Steering can turn the front wheels actively, in addition to the movements initiated by the driver. It uses an actuating system integrated into the steering column and energised by a computer.Q: What are the components of AFS? A: Active Front Steering uses a conventional steering system as in any conventional passenger car today, but with an actuator integrated into the steering column that enables an additional steering angle to be superimposed on the one chosen by the driver. By means of the power assistance, which is also the same as in a conventional vehicle, the turning moment sensed at the steering wheel can be varied. In other words, Active Front Steering is a combination of controlled power assistance and the superimposition function.Q: What advantages does AFS have over conventional steering? A: Active Front Steering increases comfort and convenience for the driver and also makes the car more agile and more stable, for instance by means of functions such as a variable steering ratio or the superimposed steering force principle. The variable steering ratio enables us to offer the driver a more direct steering ratio at low speeds and a less direct one at higher speeds. The advantage of this for the driver is that he or she can manoeuvre the vehicle when parking or in city traffic with very small movements of the steering wheel. This relieves the driver of a lot of the effort otherwise needed to turn the wheel and makes the car much easier to control. The superimposed steering principle increases the vehicle’s steering response, for instance when changing from one main-road lane to another; the car responds in a much more agile manner to the driver’s wishes. Furthermore, if a car has to be braked when the wheels on the right are on an icy surface and those on the left are on asphalt and therefore have more grip, the laws of physics mean that the car is bound to rotate around its vertical axis and turn towatds the asphalt. Active Front Steering can be used in such a situation to exert a stabilizing action, in other words to superimpose a steering movement on this natural one and guide the car back on to the straight path that the driver is trying to follow. Q: Why is there still a mechanical link between the steering wheel and the road wheels? A: Active Front Steering is a ‘by wire’ system, but retains the mechanical link between the steering wheel and the car’s front wheels. This enables a simple mechanical safety concept to be adopted. Q: Could AFS be adopted on the entire BMW model range, and when are we likely to see it on production cars? A: BMW intends to offer its customers Active Front Steering within the next four years; it is a system that in principle can be installed on any BMW model.

DS Animation brake booster, control circuit; various shots of front wheel 3-D animation of braking circuit and intergral function DS from aside, insert of wheel load and changing braking power 3-D animation of wheel load and braking power in curves DS from side, insert of wheel load and changing braking power. Motorcycle with pillion rider and load.

Q: What exactly does EMB mean, and how does it work? A: EMB is an abbreviation for Electromechanical Brake, a term that indicates the main characteristics of this brake system.Q: How does the system operate? A: We replace the conventional hydraulics of the brake systems currently in use by electro-mechanical components. There is no longer any hydraulic link between the driver’s foot on the brake pedal, the hydraulic components and the wheel brakes. All the components of the complete system are connected together electrically, in other words ‘by wire’.Q: Does the driver have a different “feeling” when braking with EMB? A: The driver presses a brake pedal down in the usual way in vehicles with EMB. The brake pedal is connected to a simulator that creates artificial feedback at the brake pedal to convey the same impression of braking effort as with a conventional brake system.Q: How is the braking force generated? A: The key element in an electro-mechanical brake system is the ‘actuator’, in which the braking force is generated. It mainly consists of an electric motor followed by planetary gears and a helical threaded spindle. The electric motor generates very little torque but runs at high speed, which is why the planetary gears are needed to reduce the speed of rotation. The spindle converts the rotary movement of the motor into the linear movement needed to generate the braking force and apply the brake pads. The EMB actuator can generate quite considerable braking forces of up to 4 tons, and its dynamic response is already comparable with a modern conventional brake system.Q: What are the advantages of EMB compared with conventional brakes? A: With an electro-mechanical brake system you can supply the ideal braking force input in all braking situations. This gives you advantages in terms of shorter braking distances and stability when braking. In day-to-day driving the benefits of the electro-mechanical braking system are evident very time a brake application is made. Pedal travel, for instance, is shorter than with a conventional brake system. Furthermore, pedal travel and the pedal actuating characteristic can be varied as required. If the anti-lock braking system takes effect, the driver no longer feels this as a pulsation or vibration at the brake pedal. Other advantages of the electro-mechanical brake system are that servicing intervals are longer and no brake fluid renewals are needed, so that there is an environmental protection benefit too. Q: Could EMB be fitted to the complete range of BMW models? A: The first vehicle to be fitted with the Electro-mechanical Brake system was the Z22, but we now know that it performs well on vehicles weighing up to about two and a half tons.Q: How far have trials of EMB progressed and when is it likely to be offered on production cars? A: At the moment we are using the electro-mechanical brake system on our experimental vehicles, but the EMB technology could be developed to production maturity within the next five years.