Patent Description:
The present invention relates to a vehicle service system and the operating method thereof.

As is known, some vehicle service systems provide for the implementation of ADAS (acronym for Advanced Driver Assistance Systems) calibration operations/functions and/or operations/functions for determining/measuring the alignment of the wheels of a vehicle.

Such vehicle service systems generally comprise target devices which are mounted on the wheels of the vehicle, and a display system capturing images of the targets of the target devices. The images of the targets are then processed by processing systems to obtain vehicle information which depends on the type of service required, i.e., ADAS calibration and/or alignment determination.

Some types of target devices of the above-mentioned vehicle service systems comprise a mechanical anchoring member, which is mounted manually in a stable but easily removable manner on the vehicle wheel, a rectangular plate-like target body having the image of the target on one face, and a rod which extends from one of the longest sides of the plate-like target body and is coupled in a freely rotatable manner to the mechanical anchoring member so that it can be rotated around a horizontal axis normally coaxial with the axis of rotation of the wheel, i.e., of its hub.

The ADAS calibration or wheel alignment determination procedures implemented by the vehicle service systems described above comprise an initial step of angularly calibrating the target devices, which involves adjusting the angular position of each plate-like target body so as to arrange it in a vertical plane.

A solution currently used for the correct angular positioning of the target bodies during the calibration step involves the use of manual measuring instruments, such as for example spirit levels, which in use are arranged resting on the plate-like body to specifically detect its vertical position.

This solution, in addition to requiring a certain time to be implemented, has the technical problem of being affected by inaccuracies in case of incorrect positioning of the instrument on the target body and/or in case of.

incorrect detection of the position of the indicator bubble by the operator.

These inaccuracies in turn introduce errors to the results provided and/or to the functions implemented by the service system, thereby causing, for example, incorrect calibration of the cameras of the vehicle's ADAS system and/or incorrect determination of the vehicle's wheel alignment.

Solutions disclosed in <CIT> and <CIT> are also known.

The object of the present invention is therefore to provide a target device and a vehicle service system which overcomes the above-mentioned technical problems.

In accordance with this object according to the present invention, a vehicle service system and the operating method thereof are provided as defined in the related independent claims, and preferably, but not necessarily, in any one of the claims dependent thereon.

The claims describe preferred embodiments of the present invention forming an integral part of the present specification.

The present invention will now be described with reference to the accompanying drawings, which illustrate a non-limiting embodiment thereof, wherein:.

With reference to <FIG> and <FIG>, number <NUM> indicates, as a whole, a vehicle service system.

According to the present invention, the vehicle service system <NUM> can be configured so as to implement/carry out an ADAS service or calibration method for a vehicle <NUM> arranged on a support surface K of a service station or area S.

According to the present invention, the vehicle service system <NUM> can also be configured so as to implement/carry out, in addition to or as an alternative to the ADAS calibration method, a service or a method for determining the alignment of the wheels <NUM> of the vehicle <NUM>.

It should be understood that in the following description the term vehicle <NUM> refers to a motor vehicle, with two or more wheels, preferably four, such as for example a motor vehicle or motorcycle.

It should also be noted that during the implementation of the ADAS calibration method, the vehicle service system <NUM> performs an ADAS calibration of the electronic sensor devices, referred to in the following as ADAS sensors (not shown) included in an Advanced Driver Assistance System (ADAS) (not shown) of the vehicle <NUM>. It should also be understood that ADAS sensors may comprise any sensor commonly present in the advanced driver assistance system of a vehicle <NUM>. For example, ADAS sensors may include a selection of the following: a radar sensor, an optical sensor, a camera, a LIDAR sensor, an ultrasonic sensor, an infrared (IR) sensor, or any similar sensor. It should also be understood that, according to the following description, the "calibration" (and/or re-calibration) function performed by the calibration method is intended so as to also include, in addition to and/or as an alternative to the "calibration", an "alignment" (or re-alignment) of an ADAS sensor.

As regards the implementation of the method for determining the alignment, the vehicle service system <NUM> can determine the alignment on the basis of the determination or measurement at least of the heeling angles that characterize the wheels <NUM> of the vehicle <NUM>. The characteristic heeling angles used by the method for determining the alignment of the wheels <NUM> may comprise one or more of the following characteristic angles: the angle of incidence, the camber angle, and the toe angle of the wheels <NUM>.

With reference to <FIG> and <FIG>, the vehicle service system <NUM> comprises one or more target devices <NUM>. The target devices <NUM> are structured to be mounted on (and disassembled from) respective wheels <NUM> of the vehicle <NUM> and are provided with respective graphic targets <NUM>.

The vehicle service system <NUM> further comprises an image acquisition unit or system <NUM>, which is designed to acquire target images containing the graphic targets <NUM> of the target devices <NUM> mounted on the wheels <NUM>.

The vehicle service system <NUM> also comprises a processing unit or system <NUM>, which is configured to process the target images to determine preliminary information associated with the ADAS calibration method and/or with the method for determining the alignment.

The preliminary information may preferably comprise, for example, the characteristic heeling angles when implementing the method for determining the alignment, and/or the position of the vehicle <NUM> relative to a predetermined reference system when implementing the ADAS calibration method.

With reference to the exemplary embodiment shown in <FIG> and <FIG>, the vehicle service system <NUM> comprises a vehicle service apparatus <NUM>. In the example shown in <FIG> and <FIG>, the vehicle service apparatus <NUM> is arranged in front of the vehicle <NUM> and can be mobile/movable (manually or by means of motorized systems) on the support surface K relative to the vehicle <NUM>. The vehicle service apparatus <NUM> may comprise, for example: a base <NUM> arranged on the support surface K preferably by means of wheels, and at least one support frame or structure <NUM> which is coupled/connected to the base <NUM> and extends above it.

With reference to the exemplary embodiment shown in <FIG> and <FIG>, the image acquisition system <NUM> is preferably included in the vehicle service apparatus <NUM> and may be provided with cameras 7a supported by the support structure <NUM>.

In the example shown in <FIG>, <FIG> and <FIG>, the image acquisition system <NUM> comprises a series of cameras 7a, for example two cameras, which are arranged on the opposite ends of a horizontal bar of the support structure <NUM>, in positions mutually laterally opposite to the support structure <NUM>, so that they can observe and capture the target images of the target devices <NUM> mounted on the wheel(s) <NUM> on the opposite sides (right and left with respect to the longitudinal axis) of the vehicle <NUM>.

The vehicle service apparatus <NUM> may also preferably comprise calibration devices <NUM> for calibrating the ADAS components of the vehicle, for example at least one panel for radar calibration and/or a panel for calibrating cameras mechanically connected to the support structure <NUM>.

The processing system <NUM> may comprise a processing and control unit 100a, which is preferably included in the vehicle service apparatus <NUM>. The processing and control unit 100a may comprise, for example, a computational unit or electronic processor (Personal Computer or laptop or the like) and is configured to at least control and supervise the operation of the devices/apparatuses/units of the vehicle service system <NUM> during the implementation of the ADAS calibration method and/or of the method for determining the alignment of the vehicle <NUM>.

In the embodiment shown in <FIG>, <FIG> and <FIG>, the vehicle service system <NUM> preferably comprises four target devices <NUM>.

It should be understood, however, that the present invention is not limited to the use of four target devices <NUM> but can also provide for the use of two target devices <NUM>. The use of four target devices <NUM> may preferably be provided for implementing the method for determining the alignment of the wheels of the vehicle <NUM> and the ADAS calibration method; the use of two target devices <NUM> may be provided for implementing the ADAS calibration method.

With reference to <FIG>, <FIG> and <FIG>, the target device <NUM> comprises a mechanical anchoring and support member <NUM>, which is designed to be coupled in a stable but easily removable manner to the respective wheel <NUM> of the vehicle <NUM>.

In the example shown in <FIG> and <FIG>, the mechanical anchoring and support member <NUM> comprises a hub or central tubular support body <NUM>, and a series of lateral anchoring jaws or arms <NUM> which are stably connected to the central tubular support body <NUM> and are designed to be operated (manually) to anchor (with a "spider" mechanical grip) the mechanical anchoring member to the wheel <NUM> (tire and/or rim).

In use, when the mechanical anchoring and support member <NUM> is anchored to the wheel <NUM>, the hub or central tubular support body <NUM> (which has a circular cross-section) is preferably arranged coaxial with the axis A of the wheel <NUM>. It should be understood that the mechanical anchoring and support member <NUM> can be operated manually to be mounted on or disassembled from the wheel <NUM>.

With reference to <FIG>, <FIG> and <FIG>, the target device <NUM> further comprises a plate-like target body <NUM> (flat plate-like), which is coupled/pivoted to the mechanical anchoring and support member <NUM> so that it can be rotated at least partially around an axis B. Preferably, the axis B is horizontal. Preferably, the axis B is coaxial with the axis A.

In the illustrated example, the target device <NUM> comprises a rectilinear pin or rod <NUM> (having a circular cross-section) which is integrally connected to the plate-like target body <NUM> from which it extends/protrudes cantilevered, and is axially engaged in the hub or central tubular support body <NUM> of the mechanical anchoring and support member <NUM> so that it can rotate around the axis B. In the illustrated example, the plate-like target body <NUM> has an approximately rectangular shape. In the illustrated example, the plate-like target body <NUM> has two opposite rectangular flat faces and has a graphic target <NUM> on at least one of the faces.

The graphic target <NUM> may contain (encode), in the form of a graphic image, at least one indication of the wheel <NUM> on which the target device <NUM> is to be mounted. Preferably, the four target devices <NUM> may comprise respective different graphic targets <NUM>, each containing a graphic indication of the respective wheel <NUM> on which they are to be mounted.

With reference to <FIG>, the target device <NUM> further comprises an electronic sensor device <NUM>. According to the invention, the electronic sensor device <NUM> is integral with the plate-like target body <NUM> (or with its rod <NUM>) so as to rotate with it around the axis B. The electronic sensor device <NUM> is configured so as to determine the angular position α of the plate-like target body <NUM> around the axis B (<FIG>). In other words, the electronic sensor device <NUM> is configured so as to determine the angle (the angular position α) of the plate-like target body <NUM> (i.e., of its lying plane) with respect to a reference axis R. The reference axis R preferably corresponds to a vertical axis (relative to the support surface K) and is perpendicular to the axis A of the wheel <NUM>. The electronic sensor device <NUM> comprises an electronic measurement circuit designed to determine the angle α based on electrical signals supplied by one or more electronic intertial sensors. Electronic inertial sensors may comprise, for example, accelerometers with one or more axes (uniaxial, biaxial or triaxial) or similar sensors.

With reference to <FIG>, the target device <NUM> further comprises a user interface device <NUM> configured to communicate to an operator information associated with the angular position α determined by the electronic sensor device <NUM>.

With reference to <FIG>, the target device <NUM> further comprises an electronic circuit or unit <NUM>, which is configured so as to determine whether the angular position α determined by the electronic sensor device <NUM> of the target device <NUM> satisfies a predetermined target angular calibration condition (target alignment condition). Preferably, the electronic unit <NUM> is also configured to control the user interface device <NUM> to provide the operator with information in response to the determined angular position α. Preferably, the electronic unit <NUM> is also configured to control the user interface device <NUM> to provide the operator with information indicative of the achievement of the angular calibration condition. Preferably, the electronic unit <NUM> is also configured to control the user interface device <NUM> so as to guide the operator step by step in the angular adjustment/displacement of the plate-like target body <NUM> around the axis B so as to assist him/her in arranging it in an angular position satisfying the target angular calibration condition.

According to a preferred embodiment shown in the attached Figures, the target angular calibration condition is satisfied/achieved when the angle α between the lying plane of the plate-like target body <NUM> and the reference axis R is substantially zero/null (angle α=<NUM>) (<FIG>). In other words, according to a preferred embodiment, the target angular calibration condition is satisfied/achieved when the lying plane of the plate-like target body <NUM> is vertical and consequently the reference axis R lies in the same lying plane as the plate-like target body <NUM>.

The Applicant has found that using the electronic sensor device <NUM> integrated in the target device <NUM> allows the angular position of the plate-like target body <NUM> to be automatically controlled in real time with very high accuracy. Tests carried out by the Applicant have shown that the angular measurement accuracy achieved is of the order of one tenth of a degree, i.e., a condition which satisfies the accuracy required in an ADAS calibration method and/or in a method for determining the alignment of the wheels.

The Applicant has also found that, by providing the operator step by step with indications on the detected angle and/or on the achievement of the target angular calibration condition through the user interface device <NUM>, the operations are simplified and therefore the times required to carry out the angular calibration of the target devices <NUM> are shortened.

According to a preferred embodiment shown in the attached Figures, the user interface device <NUM> comprises a light signalling device <NUM>. In the illustrated example, the light signalling device <NUM> may comprise one or more light sources, for example LEDs or OLEDs or similar sources.

In the example shown in <FIG>, the plate-like target body <NUM> comprises a plate-like rectangular box-shaped shell or casing <NUM>. Preferably, the casing <NUM> can be made of polymeric materials (plastic materials) or the like. Preferably, the casing <NUM> of the target device <NUM> may have thereon at least one indication (for example printed and readable) by means of which the operator uniquely identifies the wheel <NUM> on which the target device <NUM> is to be installed (for example, the following can be printed: front left wheel).

The light signalling device <NUM> can be integrated in and/or coupled to the casing <NUM>. Preferably, the light signalling device <NUM> can be advantageously arranged on one of the sides of the plate-like target body <NUM>, preferably the outer side with the smallest length (vertical and opposite to the wheel <NUM> when mounted thereon) so as to be conveniently observed by the operator during the angular adjustment of the plate-like target body <NUM>.

According to a preferred embodiment, the electronic unit <NUM> can be configured so as to control the light signalling device <NUM> to adjust the colour and/or modulate the intensity and/or vary the intermittent frequency of the light signal emitted based on the determined angular position α. The light signalling device <NUM> can generate, for example, a light signal having a first colour (for example, green), when the plate-like target body <NUM> is determined to be angularly arranged so as to satisfy the target angular calibration condition, and/or a light signal having a second colour (for example, red) when the plate-like target body <NUM> is determined not to satisfy the target angular calibration condition. According to a preferred embodiment, the electronic unit <NUM> can also control the light signalling device <NUM> in order to adjust/modulate the intermittent frequency of the light signal emitted according to the determined angular position so as to guide/assist the operator in angularly moving the plate-like target body <NUM> towards the calibration condition. For example, the intermittent frequency may decrease proportionally to the reduction of the angle α and become zero (continuous signal) at the angular position satisfying the angular calibration condition.

It should be understood that the present invention is not limited to a user interface device <NUM> comprising a light signalling device <NUM> but may alternatively or additionally provide other devices such as an acoustic signalling device, a monitor or display, or the like, contained in the target device <NUM>. The signalling mode by means of the acoustic signalling device, the monitor or the display may be analogous or similar to that described above.

With reference to <FIG>, the target device <NUM> may further comprise a wireless communication unit <NUM> for communicating bidirectionally with the processing system <NUM> by means of a wireless communication system or network (Bluetooth, WiFi or the like - not shown). It should be understood that the processing system <NUM> is provided with wireless communication modules/circuits (not shown). Preferably, the target device <NUM> can communicate to the processing system <NUM> information indicative of the angular position α of the plate-like target body <NUM>. Preferably, the electronic unit <NUM> can also be configured so as to communicate to the processing system <NUM> at least the following: information uniquely identifying the target device <NUM> that is communicating the information, and information indicating the achievement of the target angular calibration condition by the target device <NUM>.

Preferably, the electronic unit <NUM> can be configured to receive from the processing system <NUM> via the wireless communication unit <NUM> a signal for activating the angular calibration of the target device <NUM>. The electronic unit <NUM> of the target device <NUM> can be configured to control the user interface device <NUM> in response to the reception of the angular calibration activation signal, so as to signal to the operator that the angular calibration of the target device <NUM> can begin.

It should be added that the electronic unit <NUM> of the target device <NUM>, by means of the electronic sensor device <NUM>, may also be able to determine, in addition to the angle α, the orientation of the plate-like body <NUM> with respect to a reference system, in order to verify that the plate-like body <NUM> is oriented, for example, towards the support surface K (i.e., it is arranged below the rectilinear rod <NUM> (<FIG>), or in an opposite direction, i.e., towards the wheel arch 2a above the rectilinear rod <NUM> (<FIG>). In this way the electronic unit <NUM> of the target device <NUM> can also determine the achievement of the angular calibration condition based on the orientation of the plate-like body <NUM>, wherein the orientation depends on the wheel <NUM> on which the target device <NUM> is installed. According to the example shown in <FIG> and <FIG>, the calibration condition of the target devices <NUM> mounted on the front wheels <NUM> can be satisfied when the target devices <NUM> lie in a vertical plane and have a downward orientation (towards the support surface K as in <FIG>), whereas the calibration condition of the target devices <NUM> mounted on the rear wheels <NUM> can be satisfied when the target devices <NUM> lie in a vertical plane and have an upward orientation (towards the wheel arch 2a as in <FIG>).

According to the preferred embodiment shown in <FIG>, the casing <NUM> can preferably house therein an electronic board (PCB) on which the following are assembled: the electronic sensor device <NUM>, the electronic unit <NUM>, the wireless communication unit <NUM>, and a power supply device <NUM> (batteries) designed to supply the electrical power required for the operation of the target device <NUM>.

According to the preferred embodiment shown in <FIG>, the light signalling device <NUM> can be arranged on an approximately rectangular rectilinear section bar which is stably engaged in an approximately rectangular side opening of the casing <NUM> so as to close it (vertical side).

With reference to <FIG> and <FIG>, the vehicle service system <NUM> further comprises at least one electronic measuring device <NUM>. The electronic measuring device <NUM> is preferably of the hand-held type, and is structured to be positioned manually by the operator on a wheel arch 2a of the vehicle to measure its height H with respect to a surface, preferably the support surface K. Preferably, the electronic measuring device <NUM> may comprise an outer casing which is suitable to be positioned on the wheel arch 2a at a predetermined measurement point (for example, the highest point with respect to the surface K) and contains an optoelectronic measurement head or module <NUM> designed to emit a laser beam towards the support surface K to measure the height H of the measurement point of the wheel arch with respect to the support surface K, a wireless communication module <NUM>, and a processing and control module <NUM> which receives the height H measured by the optoelectronic measurement module <NUM> and communicates it via the wireless communication module <NUM> to the processing system <NUM>.

With reference to <FIG>, the method of operation of the vehicle service system <NUM> will be described below, wherein the following are assumed to be present: four target devices <NUM> provided with light signalling devices <NUM>, a laser measuring device <NUM>, and a vehicle service apparatus <NUM> arranged in front of the vehicle <NUM> at the service station S.

It is assumed that the operator has mounted the four target devices <NUM> on the respective wheels <NUM> of the vehicle <NUM> by means of the respective mechanical anchoring and support members <NUM>. It is also assumed that the operator has switched on the target devices <NUM>, for example by means of a switch (not shown) which can be present in the target devices <NUM>. In this phase, the target devices <NUM> can remain in a waiting condition for an activation signal. In this phase, the light signalling devices <NUM> of the four target devices <NUM> can generate a first light signal indicative of a waiting condition for the start of the angular calibration. The first light signal could be, for example, a continuous red signal.

The activation signal can cause a change in the state of the light signal of one of the target devices <NUM> to indicate to the operator that the latter must be the first to be calibrated on the basis of a predetermined calibration ordered sequence. In this phase, for example, the light signal of the first target device <NUM> to be calibrated (the target device on the front left wheel in <FIG>) may temporarily change from a continuous light state to an intermittent light state (intermittent red signal) to attract the operator's attention. In this phase, the remaining target devices <NUM> can maintain their own signalling state (continuous red signal).

The intermittent light state can end automatically, for example after a predetermined time or as soon as an angular change in the plate-like target body <NUM> around the axis B is detected by the electronic sensor device <NUM>, indicating the start of manual adjustment by the operator. During the manual rotation performed on the plate-like target body <NUM>, the electronic sensor device <NUM> measures the angle α step by step and communicates it to the electronic unit <NUM> which determines whether or not the predetermined angular calibration condition has been reached. When the electronic unit <NUM> detects that the angular calibration condition has been reached (i.e., the plate-like target body is arranged in the vertical plane), it commands the light signalling device <NUM> to change the state. The change in the state may involve a change in the light signal from the first light signal to a second light signal different from the first one. The second light signal may comprise, for example, a continuous green signal (F1 in <FIG>) which signals to the operator that the angular calibration of the first target device <NUM> is correct and complete. In this phase, the remaining three target devices <NUM> can continue to maintain the first light signal (continuous red signal) unchanged, to signal that they have not yet been calibrated (NC in <FIG>).

Once the calibration condition has been reached (green light signal), the first target device <NUM> can communicate to the processing system <NUM> an electrical calibration confirmation signal indicating the completion of the angular calibration of the first target device <NUM>.

The processing system <NUM>, in response to the reception of the calibration confirmation signal from the first target device <NUM>, can transmit the activation signal to the second target device <NUM> provided in the predetermined calibration ordered sequence. For example, in <FIG>, the activation signal is communicated to the target device <NUM> applied to the left rear wheel. In this phase, the activation signal causes a change in the state of the light signal of the second target device <NUM> to indicate to the operator that the latter must be the second to be calibrated on the basis of the calibration ordered sequence. In this phase, the light signal of the second target device <NUM> to be calibrated (the target device on the rear left wheel in <FIG>) may temporarily change from the continuous light state to the intermittent light state to attract the operator's attention. In this phase, the third and fourth target devices <NUM> to be calibrated maintain their own signalling state (NC in <FIG>) corresponding to the continuous red signal, and the first target device <NUM> maintains its own signalling state (F1 in <FIG>) corresponding to the green signal indicating that the angular calibration has been carried out.

The intermittent light state of the second target device <NUM> can end automatically, for example after a predetermined time or as soon as an angular change in the plate-like target body <NUM> around the axis B is detected by the electronic sensor device <NUM>. When the electronic unit <NUM> detects that the angular calibration condition has been reached (vertical plate-like target body of the second target device <NUM>), it commands the light signalling device <NUM> to change the state from the first signal to the second light signal different from the first. The second light signal may comprise, for example, a green light (F2 in <FIG>) which signals to the operator that the angular calibration of the second target device <NUM> is correct. Once the calibration condition has been reached (green light signal), the second target device <NUM> can communicate to the processing system <NUM> a calibration confirmation signal indicating the completion of the angular calibration of the second target device <NUM>. The processing system <NUM>, in response to the reception of the calibration confirmation signal from the second target device <NUM>, can transmit the activation signal to the third target device <NUM> provided in the predetermined calibration ordered sequence. For example, in <FIG>, the activation signal is communicated to the target device <NUM> applied to the right rear wheel.

The operations described above are repeated in the same way according to the predetermined ordered sequence during the angular calibration of the third target device <NUM> (<FIG>) and the angular calibration of the fourth target device <NUM> (<FIG>). It should be understood that during these calibrations the third and fourth target devices <NUM> signal to the operator that the respective angular calibration conditions have been achieved by generating the light signals F3 (<FIG>) and F4 (<FIG>), respectively.

Once the angular calibration of the four target devices <NUM> has been completed, i.e., following the reception of the confirmation signal transmitted by the fourth target device <NUM>, the processing system <NUM> communicates to the target devices <NUM> an angular calibration end signal. In response to the reception of the angular calibration end signal, the light signalling devices <NUM> of the target devices <NUM> can be controlled by the corresponding electronic units <NUM> to change their light state, for example from on to off.

With reference to <FIG>, the processing system <NUM> can be configured to guide the operator through the target devices <NUM>, in the operation of measuring the heights H of the wheel arches 2a in a predetermined sequential order.

With reference to <FIG>, the processing system <NUM> can transmit a wheel arch measurement activation signal to the first target device <NUM> arranged on the wheel <NUM> associated with the first wheel arch 2a to be measured. In response to the reception of the wheel arch measurement activation signal, the electronic unit <NUM> of the first target device <NUM> (<FIG>) can command a change in the state of the light signal emitted by the light signalling device <NUM> to indicate to the operator that the wheel arch 2a on which the height measurement is to be carried out is the one above the wheel <NUM> with which the first target device <NUM> is associated. In this phase, the light signalling device <NUM> can pass from a first state, for example off, to a second state, for example on (red light signal). The operator places the electronic measuring device <NUM> on the first wheel arch 2a and measures the height H1. The measured height H1 is communicated by the electronic measuring device <NUM> to the processing system <NUM> via its communication module <NUM>. The processing system <NUM> receives the measured height H1 and stores it in a database (for example, in an internal memory) assigning it to/associating it with the first wheel arch 2a.

The processing system <NUM> can communicate a read confirmation signal to the first target device <NUM> to cause its light signalling device <NUM> to change its light state to signal to the operator that the reception and storage of the height has been completed by the processing system <NUM>. For example, in this phase the light signal of the first target device <NUM> can change from red to green (M1 in <FIG>).

With reference to <FIG>, the processing system <NUM> can transmit a wheel arch measurement activation signal to the second target device <NUM> arranged on the wheel <NUM> associated with the second wheel arch 2a to be measured. In response to the reception of the wheel arch measurement activation signal, the electronic unit <NUM> of the second target device <NUM> (<FIG>) can command a change in the state of the light signal emitted by the light signalling device <NUM> to indicate to the operator that the wheel arch 2a on which the height measurement is to be carried out is the one above the wheel <NUM> with which the second target device <NUM> is associated. In this phase, the light signalling device <NUM> can pass from a first state, for example off, to a second state, for example on (for example, red light signal). The operator places the electronic measuring device <NUM> on the second wheel arch 2a and measures the height H2. The measured height H2 is communicated by the electronic measuring device <NUM> to the processing system <NUM>. The processing system <NUM> receives the measured height H2 and stores it in a database, assigning it to/associating it with the second wheel arch 2a.

The processing system <NUM> can communicate a read confirmation signal to the second target device <NUM> and its light signalling device <NUM> can change its light state to signal to the operator that the processing system <NUM> has completed the operation of storing the measured height H2 of the second wheel arch 2a. For example, in this phase the light signal state of the second target device <NUM> can change from red to green (M2 in <FIG>).

The operations described above are repeated in the same way according to the predetermined ordered sequence during the measurement of the height H3 of the third wheel arch 2a, and of the height H4 of the fourth wheel arch 2a. In these phases, the light signalling devices <NUM> of the third and fourth target devices <NUM> signal to the operator the completion of the acquisition of the measured heights H3 and H4, thereby causing a change in the state of the light signal of the third target device <NUM> (M3 in <FIG>) and of the fourth target device <NUM> (M4 in <FIG>).

It should be pointed out that the processing system <NUM> can also communicate the stored heights H3 and H4 of the third and fourth wheel arches 2a to the central unit of the vehicle (not shown) which in turn processes them on the basis of the service performed by the vehicle service system <NUM>.

A technical effect of the method described above is to assist the operator in measuring the wheel arch heights in the correct sequence, thus reducing execution times and eliminating errors. Moreover, the ordered measurement sequence and the automatic transmission of the heights by the measuring device eliminates the need for the operator to manually enter the heights detected in the processing system <NUM>.

The above-described service system has the advantage of increasing the accuracy of the manual angular calibration of the target devices and of reducing the execution time thereof.

The above-described service system has also the advantage of reducing the time required to carry out measurements of the wheel arch heights and of carrying out an automatic storage thereof.

Claim 1:
A target device (<NUM>) comprising:
a mechanical anchoring and support member (<NUM>), which is designed to be coupled in a stable but easily removable manner to a respective wheel (<NUM>) of the vehicle (<NUM>),
a plate-like target body (<NUM>), which is coupled to said mechanical anchoring and support member (<NUM>) in order to be rotated at least partially around a substantially horizontal axis (B) and has said graphic target (<NUM>) on at least one face,
an electronic sensor device (<NUM>) which is integral with said plate-like target body (<NUM>) in order to rotate with it around said axis (B), and is configured in order to determine the angular position (α) of said plate-like target body (<NUM>) around said axis (B), said electronic sensor device (<NUM>) comprises an electronic measurement circuit configured to determine said angular position (α) based on electrical signals supplied by one or more electronic inertial sensors,
a user interface device (<NUM>) configured to communicate to an operator information associated with said determined angular position (α).