(10) DE 10 2004 012 501 A1 Junw 12, 1004

Description

State of the Art

[0001] The invention relates to a method for operating a navigation system for motor vehicles, as disclosed, for example, in the EP 0 734 007 B1. Such navigation systems, which are becoming increasingly more useful in motor vehicles, exhibit, in particular, a sensor unit for determining the position data, an evaluating unit for processing the position data and an output unit for visual and/or audible output of the position data. In order to verify the growing functionality of navigation systems, test drives with the navigation system, implemented in the motor vehicle, are conducted (in particular, during the development phase of a navigation system). During the test drive the test personnel evaluates the hardware and the software of the navigation system.

[0002] The drawback with this procedure is that these test drives, which are conducted under a variety of conditions that cannot be reproduced, incur (in particular, also during test drives in foreign countries) a high cost in test personnel, expenses, time and equipment (for example, motor vehicles) and that different versions and/or development stages of a navigation system and/or a variety of navigation systems of different manufacturers can be compared only to a limited extent.

Technical Problem

[0003] The invention is based on the problem of providing a method of the type described in the introductory part and which provides a simple possibility of verifying in a repeatable way the operating mode of the navigation systems.

[0004] The invention solves this problem with the characterizing features of patent claim 1.

[0005] Advantageous embodiments of the invention are an essential part of the additional patent claims.

[0006] In the method, according to the invention, the navigation system is verified with respect to its mode of operation (the way it works) - in particular, with respect to the functionality and/or scope of functions and/or implemented innovations or modifications - with the aid of a simulation system that depicts a simulated trip of the motor vehicle (that is, simulates an actual trip of the motor vehicle). To this end, the navigation system is actuated by the simulation system during the simulated trip with certain control data, which are characteristic for the operating mode of the navigation system or control signals obtained from said control data. With the use of the simulation data, generated by the navigation system during the simulated trip, the navigation system is verified.

[0007] In order to generate the control data, the first step is to determine certain reference data, which are needed for stimulating a navigation system (a quasi standard data set) during an (actual) reference drive, which is carried out with the aid of a data recording unit ("data logger"). These reference data are recorded and stored on a suitable data carrier - for example, a hard disk, CD, DVD, etc. If desired, before or after the data are recorded by the data recording unit ("data logger"), the data may be processed. During the reference drive at least those sensor data are determined and recorded as the reference data that are typical for determining the position of the motor vehicle - in particular, the sensor data that can be used for a rough estimate of the position of the motor vehicle (accuracy ranging, for example, from 10 m to 15 m). To this end, preferably position data of a satellite based position locating system are used, in particular GPS data. Preferably, however, during the reference drive, even more sensor data are also determined and recorded as the reference data; these reference data can be used for an exact determination of the position of the motor vehicle (accuracy, for example, approximately 2 m). To this end, especially the sensor data that are typical for the selected route to be driven during the reference drive and/or for the road conditions of the reference drive and/or for determining the distance travelled by the motor vehicle during the reference drive, are used; these sensor data may be, for example, the acceleration data for determining the acceleration of the motor vehicle (for example, with the use of angle of rotation sensors or, for example, gyro sensors) and/or speed data for determining the speed of the motor vehicle and/or the reverse drive data for determining the reverse drives of the motor vehicle (for example, with the use of suitable distance measuring sensors or, for example, speed sensors and/or reverse drive sensors, for example, for verifying whether the reverse speed gear has been selected). Optionally in addition to the sensor data, it is possible during the reference drive to determine and record also visual data and/or audible data as the reference data, which are brought into phase (are synchronized) preferably with the sensor data. In this context the visual data may be determined and recorded, for example, by shooting video films, which are time synchronized (brought into phase with the sensor data) with the corresponding sound during the reference drive - for example, by recording the distance travelled by the motor vehicle from the viewpoint of the driver of the motor vehicle and/or by recording specific control operating elements, relating in particular to the navigation system of the motor vehicle, in particular a monitor screen and/or the instrument cluster of the motor vehicle that serves as the display unit of the navigation system. In this case the audible data may be determined and recorded, for example, by recording the audible communication of the driver of the motor vehicle with the navigation system during the reference drive, these audible data being time synchronized (brought into phase with the sensor data). These audible data may be determined and recorded by recording the voiced instructions of the driver and/or the navigation instructions of the navigation system. In addition, the interaction of the driver of the motor vehicle with the navigation system during the reference drive can also be recorded.

[0008] The reference data, in particular the sensor data, recorded on the data carrier, and optionally the recorded visual and/or audible data are imported into the simulator system, if desired, after processing (conversion) into a format that is suitable for the simulation system and can be used either immediately or after a data conversion as the control data for the navigation system.

[0009] With the use of these control data the navigation system that is to be verified is actuated by the simulation system; and, thus, a simulated trip is carried out on the basis of the reference data, determined during the reference drive, as the standard data. Consequently during this simulated trip the navigation system that is to be verified is fed by the simulation system with all of the information that is available owing to the reference data and acquired during an actual trip of the motor vehicle. The control signals, required for the simulated trip, are generated as the input signals of the navigation system by means of the control data using suitable devices of the simulation system. In particular, the control data produce through simulation the control signals, which correspond to the sensor data. Thus, the GPS signal, required for determining the position data, is generated, for example, by means of a GPS simulator; the angle of rotation sensor, required for determining the acceleration data of the motor vehicle, is generated, for example, by means of a rotary table; the speed signals, required for determining the speed of the motor vehicle, are generated, for example, by means of analog or digital simulated wheel pulses. In synchronization thereto, during the simulated trip the simulation system can reproduce the visual data (video films, if desired, with sound etc.) and/or the audible data that have been determined and recorded, if desired, during the reference drive, thus making it possible to coordinate the driving instructions during the simulated trip with the actual road situations of the reference drive. The course of events during the simulated trip can be recorded and documented by means of optical and/or acoustical devices (in particular, cameras and microphone) attached to the simulation system.

[0010] Based on the conducted simulated trip, the navigation system, which is to be verified, generates and displays the simulation data as the simulation results - for example, even visual and/or audible simulation data, which are stored on a suitable data carrier, preferably on the data carrier, which is also used for storing the reference data.

[0011] In order to evaluate the results of the simulation, the reference data are compared with the simulation data - for example, by parallel rendering of the corresponding visual data on a monitor screen and/or within the scope of an automatic evaluation by means of automated visual comparison processes - for example, by means of image detection methods and/or image overlay methods ("video overlay") and/or differential imaging methods. Furthermore, during the evaluation, it is possible to use certain reference points, which were generated by means of audible data (for example, by means of voice output). As the markers or trigger points, these reference points offer the option of a selection or choice or enable an indexing during the process of comparing the reference data with the simulation data. The evaluation for verifying the operating mode of the navigation system can be carried out, according to the specification, by the test personnel or as a function of the test conditions in an automated way (operator independent) or operator dependent either as early as during the simulated trip or following the simulated trip by means of the recorded results of the simulation.

[0012] The proposed method with the aid of the simulation system allows in an advantageous way the operating mode of any number of navigation systems to be verified repeatably in a simple way and at low cost under standardized conditions:

- A reference drive, incurring a high cost in time, expenses, personnel and equipment, has to be carried out only once in order to determine (standardized) reference data, whereas a simulated trip, which runs automatically at a low personnel cost, can be carried out repeatably an arbitrary number of times and under the exact same conditions.

- It is possible to verify in a simple way a specific navigation system with respect to its functionality and/or range of functions and/or innovations, such as software modifications or hardware changes. Therefore, any errors can be reproduced and analyzed with negligible complexity; and the software developments or hardware developments and the resulting changes in the dynamic behavior of the navigation system can be automatically documented.

- Different navigation systems (for example, navigation systems of different manufacturers) can be tested and compared with respect to their functionality and/or scope of functions and/or innovations.

Embodiment

[0013] One embodiment of the invention shall be explained in conjunction with the drawings (Figure 1 to Figure 3).

[0014] In this case

[0015] Figure 1 is a schematic rendering of the reference phase with the generation of reference data and control data.

[0016] Figure 2 is a schematic rendering of the simulation phase with the generation of simulation data during the simulated trip.

[0017] Figure 3 is a schematic rendering of the evaluation phase with the comparison of simulation data with the reference data.

[0018] The navigation system of a motor vehicle exhibits, for example, the following components:

- a sensor unit, which is used for determining the position data of the motor vehicle and for determining the geographical position of the motor vehicle by means of the GPS data, transmitted by a satellite system; by means of the acceleration data, delivered by an angle of rotation sensor (gyro sensor); and by means of the speed data and the reverse drive data of the motor vehicle, delivered by the distance measuring sensors.

- an evaluating unit, which is used for transmitting the geographical position of the motor vehicle on a digital road map and which has a data storage unit (for example, a CD-ROM or hard disk or DVD),

- an output unit, which is used for outputting the location of the motor vehicle to the digital road map and/or for outputting audible and/or visual destination finding instructions to the operator of the motor vehicle and which exhibits as the display units a monitor screen and a display in the instrument cluster.

[0019] In order to verify the operating mode of the navigation system, a simulation system is used. During a simulated trip the simulation system actuates the navigation system with the control signals, which act as the stimuli.

[0020] According to Figure 1, in order to generate control data from the standardized reference data 10, the first step is to generate the reference data 10 in a reference phase during an (actual) reference drive of the motor vehicle. To this end, in particular sensor data 11 are determined, for example, on the basis of a GPS signal 12, which is generated by a GPS receiver 3; an acceleration signal 13, generated by a gyro sensor 4; a reverse drive signal 14, generated by a reverse drive detector 5; and a speed signal 15, generated by a speed sensor 6. These sensor data 11 are recorded by means of the recording unit 1 ("data logger") during the reference drive of the motor vehicle. This process produces the reference data 10 with or without processing. Furthermore, during the reference drive of the motor vehicle visual data 16 and audible data 17 are also recorded as the reference data 10. In particular, a video recording is made from the viewpoint of the driver of the motor vehicle by means of the video camera 7; and an audible recording of the navigation instructions is made by means of a microphone 8.

[0021] The sensor data 11, recorded by means of the recording unit 1 during the reference drive of the motor vehicle, and the visual data 16 and the audible data 17, both of which are recorded during the reference drive of the motor vehicle, are fed to a data storage unit 2, where they are stored as a common set of reference data 10. For example, a hard disk or DVD or CD-ROM is envisaged as the data storage unit 2.

[0022] According to Figure 2, in a simulation phase for carrying out the simulated trip the reference data 10, stored in the data storage unit 2, are imported as the control data 20 into the simulation system 30. The simulation system 30 uses the control data 20, following a conversion, as the database for the simulated trip of the motor vehicle that is simulated by the simulation system 30. The information, required to display the simulated trip on the navigation system 50, is generated on the basis of the control data 20 by means of the suitable devices of the simulation system 30. Hence, within the scope of the simulation the navigation system 50 is actuated with the control signals 40, generated on the basis of the control data 20. Some examples of devices of the simulation system 30 for generating the control signals 40 are a GPS transmitter (antenna) 31 for simulating a GPS signal 41 (which is passed on, for example, by means of a GPS receiver to the navigation system 50), a rotary table 32 for simulating an acceleration signal 42, wheel sensors 33 for simulating a speed signal 43, a simulation computer for simulating a backup light signal 44, a monitor screen 35 for evaluating visual signals 45 and a voice output unit 36 for evaluating audible signals 46. During the simulated trip, carried out on the basis of the reference data 10, the navigation system 50 is actuated with these control signals 40. This process generates the simulation data 60, which correspond to the reference data 10 and which are outputted, for example, visually on a monitor screen 51 of the navigation system 50.

[0023] According to Figure 3, in an evaluation phase for evaluating the simulated trip and/or the simulation data 60, the simulation data 60 of the navigation system 50 that are determined during the simulated trip are recorded on a data carrier - for example, by means of visual and audible recording of the simulated trip by means of a video camera 62. In order to evaluate the simulated trip and, thus, in order to verify the navigation system 50, the simulation data 60, which are stored by recording the simulated trip, are compared with the data 10, in particular by means of a visual comparison of the visual data 16, acquired during the reference drive (video from the viewpoint of the driver of the motor vehicle) with the visual simulation data 61, acquired during the simulated trip by means of the visual display 51 of the navigation system 5. In this way the visual comparison can be carried out by means of a visual display unit 70 (for example, by means of a television monitor), on which the visual reference data 16 of the reference drive are placed opposite the visual simulation data 61 of the navigation system 50, said simulation data being generated during the simulated trip. At the same time for a detailed evaluation the visual data 16 can be synchronized with the visual simulation data 61 by means of indexing on the basis of trigger points 63 (for example, generated and reproduced by audible means). These trigger points 63, representing, for example, distinctive positions 65 (for example, crossings, junctions or side road crossings, etc.) during the reference drive, can be recorded and stored as the audible data 17 during the reference drive and can be stored at a later date as audible markers 64 when creating the simulation data 60. During the comparison with the simulation data 60, the trigger points 63 or rather the distinctive positions 65 can be used for indexing and/or facilitating the choice of specific road situations or road sections on the map 71, shown on the display unit 70 on the basis of the simulation data 60.

List of Reference Numerals P5107/EIS2612

1	Data recording unit	34
2	Data storage unit	35	Monitor screen
3	GPS receiver	36	Loudspeaker
4	Gyro sensor	40	Control signals
5	Reverse drive detector	41	GPS signal
6	Speed sensor	42	Acceleration signal
7	Video camera	43	Speed signal
8	Microphone	44	Backup light signal
10	Reference data	45	Visual signals
11	Sensor data	46	Audible signals
12	GPS signal	50	Navigation system
13	Acceleration signal	51	Monitor screen navigation system
14	Speed signal	60	Simulation data
15	Reverse drive signal	61	Visual simulation data
16	Visual data	62	Video camera
17	Audible data	63	Trigger points
20	Control data	64	Audible markers
30	Simulation system	65	Distinctive positions
31	GPS transmitter	70	Monitor screen
32	Rotary table	71	Map on the monitor screen
33	Wheel sensors

Patent Claims

1. Method for operating a navigation system for a motor vehicle, characterized in that the navigation system (50) is actuated by a simulation system (30), which is provided for carrying out a simulated trip of the motor vehicle, during a simulated trip with control signals (40), which are typical for the operating mode of the navigation system (50),

and that the simulation data (60), generated by the navigation system (50) during the simulated trip, are determined and used for verifying the navigation system (50).

2. Method, as claimed in claim 1, characterized in that the control signals (40) of the simulation system (30) that are typical for the operating mode of the navigation system (50) are generated from the reference data (10), determined by means of a previous reference drive.

3. Method, as claimed in claim 2, characterized in that the reference data (10), which are determined during the reference drive, are recorded,

that the recorded reference data (10) are introduced as the control data (20) into the simulation system (30),

that the simulation system (30) carries out a simulated trip of the motor vehicle, during which trip the navigation system (50) is actuated by the control signals (40), which are generated with the use of the control data (20), provided by the simulation system (30),

and that for verifying the operating mode of the navigation system (50), the simulation data (60) of the navigation system (50) are compared with the reference data (10), said simulation data being determined during the simulated trip of the motor vehicle and corresponding to the reference data (10).

4. Method, as claimed in claim 2 or 3, characterized in that the reference data (10) are determined at least by means of sensor data (11), which are typical for determining the position of the motor vehicle.

5. Method, as claimed in claim 4, characterized in that at least the position data (12), transmitted by a satellite based location finding system, are used as the sensor data (11).

6. Method, as claimed in claim 4 or 5, characterized in that additional acceleration data (13) and/or reverse drive data (14) and/or speed data (15) are used as the sensor data (11).

7. Method, as claimed in any one of the claims 2 to 6, characterized in that additional visual data (16) and/or audible data (17) are used as the reference data (10).

8. Method, as claimed in any one of the claims 1 to 7, characterized in that the simulation system (30) generates the control signals (40), required for operating the navigation system (50), by means of suitable devices (31, 32, 33) of the simulation system (30).

9. Method, as claimed in any one of the claims 3 to 8, characterized in that in order to verify the operating mode of the navigation system (30), the reference data (10) are compared visually with the simulation data (60) of the navigation system (30).

----------------------------------

3 sheets of drawings to follow.

---------------------------------