This invention relates to a motor-vehicle driving simulator, particularly for teaching purposes.

Driving simulators are known where some of the typical manoeuvres involved in driving a motor-vehicle are recreated by means of electrical and electronic devices receiving their inputs from controls operated by the learner. US-A-3 171 215 shows, for instance, an apparatus comprising an endless belt display showing the picture of a winding road, a steering wheel adapted to displace a pointer in front of the display, and an accelerator and a brake pedal for varying the speed of the belt, while no provision is made for simulation of the clutch and gearshift.

Such known simulators are unable to give a true or realistic replica of the actual conditions of operation of the controls, and in particular they fail to train the learner in the coordination of the commands, so that their effectiveness is small or nonexistent for the purposes of learning.

More particularly, prior simulators do not give the learner an accurate feeling of the efforts and displacements required for operating the gearbox lever and the clutch, brake and accelerator pedals, or the force required for turning the steering wheel. Consequently, when the learner starts taking practical motoring lessons aboard a real motor-vehicle, he not only fails to take advantage of his previous experience at the simulator, but he often turns out to have acquired wrong habits, which hamper learning and cause harmful stresses to the motor-vehicle.

A device for teaching the learner in the use and coordination of the clutch and gearshift is disclosed in US-A-4 150 497, though this is not a simulator but rather an attachment for a motor-vehicle running in actual road situations, so that it can only be used for advanced training of an already skilled driver, not for teaching the rudiments of driving.

It is not feasible to improve the known simulators in order to more truly reproduce the behaviour of a real motorcar, because the sophistication involved would push design and manufacture costs to levels unacceptable for commercial production.

The invention therefore has as its main object to provide a motor-vehicle driving simulator where the main motoring controls are realistic in contrast to being reproduced with uncertain approximation, so that the learner will find, in actual motoring on a motorcar, an exact match with the manoeuvres that he has learnt at the simulator, while maintaining costs of design and manufacture that are moderate and even lower than for known simulators.

A further object is to provide a simulator by which real traffic situations can be reproduced, the learner having to react with appropriate manoeuvres, without causing the simulator to stop.

In order to achiveve the above and other objects, such as will appear from the following detailed specification, this invention provides a motor-vehicle driving simulator, particularly for teaching purposes, having the features defined in claim 1. ¹

Further features and advantages will appear from the following detailed disclosure, with reference to the attached drawings, given by way of non-limiting example, and wherein:

• Fig. 1 is a perspective view, partly broken away, of a simulator according to the invention;
• Fig. 2 is a perspective view showing a detail of an engine unit belonging to the simulator of Fig. 1 and of a driving electric motor therefor;
• Fig. 3 is a perspective view showing another detail of the engine unit;
• Fig. 4 is a mechanical diagram of the complete simulator;
• Fig. 5 is an electrical block diagram of a controlled supply unit for the motor;
• Fig. 6 is a detail of the diagram of Fig. 5;
• Fig. 7 is a block diagram of a logic circuit controlling said supply unit;
• Fig. 8 is a detailed electric diagram of said logic circuit.

With reference to Figs. 1 to 4, a simulator referenced with 10 comprises a stationary frame 14 in which a driver's seat 11 is provided. The stationary frame also supports a rotary steering wheel 12, a gearbox lever 13, and a set of pedals comprising: a clutch pedal 15, a brake pedal 16 and an accelerator pedal 17. A boot 20 mounted on the stationary frame in front of the driver's seat accommodates a pair of rollers (of which only roller 19 is visible in the Figures) around which a ribbon 18 is looped. The ribbon is placed for comfortable viewing through a window from the driver's seat. A road course, with possible obstacles, is marked in contrasting colours on the ribbon.

A pointer 21, driven by the steering wheel 12, is displaceable across the ribbon in order to follow the road course as this winds before the driver while the ribbon unrolls, as it will be explained later. A light detector (not shown) is mounted on pointer 21 for sensing the course traced on the ribbon and for energizing a light or sound alarm whenever the learner, by incorrectly operating the steering wheel, allows the pointer to stray from the course.

An engine unit 30 of a real motorcar is housed in the front boot 20 and comprises an internal combustion engine 31 (or at least its crankcase) with its crankshaft 37, gearbox 32, a friction clutch 29 coupled between the engine and the gearbox, and a differential gear adapted to transmit a rotary motion from the gearbox output to respective right-hand and left-hand axle shafts 33 and 34, including their brakes comprising disks 35 and hydraulic shoes 36.

Engine unit 30 is preferably taken from a front- wheel drive motorcar, so that all or most of the above mechanical members are housed within a single block. The engine unit 30 is preferably recovered from damaged or unserviceable motorcars, and is stripped of any superfluous members such as cranks, pistons or valves, in order to reduce the power required for turning crankshaft 37, as explained below.

As shown in the mechanical diagram of Fig. 4, crankshaft 37 has a pulley 37a that is driven by an electric motor 40, by means of a belt transmission 38. Another belt transmission 39 connects one of the axle shafts 33 with roller 19, in order to drive the ribbon synchronously with the output speed of the gearbox.

Clutch pedal 15 is operatively connected to the control member of clutch 29, and brake pedal 16 is operatively connected to the braking system, by means of conventional couplings, substantially the same as in a real motorcar. The accelerator pedal 17 operates a rheostatic speed regulator 42, adapted to vary the supply voltage to motor 40. Regulator 42 could also be of any other type, depending on the motor chosen.

The block diagram of Fig. 5 shows a supply unit for motor 40. The supply voltage at terminals V is applied, through a differential overload relay 50, to contacts 51 of a power relay R (also see Fig. 6), through which the rheostatic regulator 52 is energized. Overload relay 50 also energizes a low-voltage, d.c. supply unit 57. The latter supplies: a lock-operated switching unit 53, controlling the energeization of power relay R, and adapted to be operated by an ignition key CH; power relay R; a set of position-detectors 54 for detecting the position of the controls; and a logic circuit 55 adapted to disable the supply according to the states of said position- detectors.

Fig. 6 shows switching unit 53 in detail. A first (bistable) contact 60 connected in series with power relay R is closed by a first step of the ignition key CH; a second (monostable) series contact 61 is closed by the second step of said key (with spring back). Two series-connected contacts, i.e. a holding contact 62, and a blocking contact 63 controlled by logic circuit 55, are connected in parallel with contact 61.

The simulator has a logic circuit 55 controlling the motor according to the following functions:

• prevent motor 40 from being started while a gear is engaged in the gearbox and clutch 29 is engaged;
• disable the supply to motor 40 if the gearbox lever is operated while the clutch is engaged;
• disable the supply to motor 40 if the clutch pedal is released too quickly while a gear is engaged;
• disable the supply to motor 40 if the crankshaft rotation speed falls below a predetermined threshold.

Logic circuit 55 is shown in Fig. 7, and comprises: input stages 71 to 74, driven by respective detectors S1 to S4 of the set 54; a pair of flip-flops 75 and 76 for storing the states of detectors S1 to S4 and a logic gate 77 driven by said detector states for opening contact 63 and thereby de-energizing power relay R (e.g. via an interface transistor and a corresponding block relay, not shown), when one of the conditions listed in the preceding paragraph becomes true.

Detectors S1 to S4 have the following, functions:

• S1 detects the home position of clutch pedal 15;
• S2 detects the depressed position of clutch pedal 15;
• S3 detects the neutral position of the gearbox lever 13;
• S4 detects the low speed threshold of motor 40.

Fig. 8 is a detailed electric diagram of a preferred embodiment of logic circuit 55, which should be immediately intelligible to a person skilled in the art, based on the above explanation. Inputs 11 to 14 from detectors S1 to S4 are coupled to the rest of the circuit by means of optocouplers IC1 to IC4. Outputs A are connected in parallel to the base of an interface transistor (not shown) for operation of the block relay.

By way of example, the commercial identifications of most of the parts included in the circuit of Fig. 8 are given below:

Of course, the circuit could be made with other, equivalent parts, possibly comprising chips of a higher integration level.

The practical details of the simulator could be changed to a large extent with respect to the embodiment disclosed and shown in the drawings by way of non-limiting example. In particular, the display means embodied in the ribbon might be replaced by a television monitor such as a cathode ray tube driven by a pre-recorded television signal, for displaying a desired road course.