Optical detection device for monitoring a surveillance area having inspections for functional safety - Patents.com

Abstract

A method for controlling an optical detection device (12), a detection device (12) and a vehicle (10) having at least one detection device (12) is described. In the method, at least one light emitting element (40) is activated to transmit at least one optical signal (42). At least one reflected optical signal (60) is received using at least two receiving areas of at least one receiver (52). At least one receiving variable (54) is determined using the at least one received optical signal (42). Functional safety of the detection device (12) is at least intermittently tested. The duration of the transmission of each of the optical signals (42) is limited to a specified transmission time interval. To achieve eye safety of the detection device (12), at least one measurement receiving area is generated using at least one measurement receiving area to characterize the amount of light captured during a measurement time interval. At least one test receiving area is generated using at least one test receiving area to characterize the amount of light captured during a test time interval. The test time interval is greater than the measurement time interval and the test time interval is greater than the transmission time interval. If the test receive quantity characterizes an amount of light that is greater than the amount of light characterized by the measured receive quantity beyond a predetermined tolerance, a fault condition is generated.

Description

[Technical field]

[0001] The present invention relates to a method for operating an optical detection device arranged to monitor at least a monitoring area, comprising the steps of: At least one light emitting element is activated to transmit at least one optical signal; At least one reflected optical signal is received using at least two receiving areas of at least one receiver; determining at least one received variable using the at least one received optical signal; The functional safety of the detection device is checked at least intermittently; It concerns the method.

[0002] The present invention also provides an optical detection device for monitoring at least one monitoring area, comprising: having at least one light emitting element for transmitting an optical signal; having at least two receiving areas for receiving the reflected optical signal; at least one means for determining a reception variable from a received optical signal; at least one means for controlling the optical detection device and for processing the received variables, having at least one means for checking the functional safety of the detection device, It relates to optical detection devices.

[0003] Furthermore, the present invention relates to a vehicle having at least one detection device for monitoring at least one monitoring area, the at least one detection device comprising: at least one light emitting element for transmitting an optical signal; at least two receiving areas for receiving the reflected optical signals; at least one means for determining a reception variable from the received optical signal; at least one means for controlling the optical detection device and for processing the received variables; At least one means for checking the functional safety of the detection device; The present invention relates to a vehicle having a [Background technology]

[0004] A method for calibrating an optical scanning system is known from DE 10 2017 223 618 A1. The method starts with a step in which an optical transmitting unit transmits a laser line, which is transmitted during the dark phase to a rear area of ​​the housing. In other words, the optical scanning system emits to the rear or rear area of ​​the housing, which is opaque to the optical line. In a subsequent step, the laser line is redirected using a reflector unit arranged in the rear area of ​​the housing. This means that the reflector unit redirects the laser line so that it is received or captured by the optical receiving unit immediately, i.e. without interacting with objects from the outside surroundings of the housing. In a subsequent step, the laser line redirected or deflected by the reflector unit is received by the receiving unit. In a subsequent step, the orientation of the laser line is determined and in a subsequent step, based on the orientation of the laser line, the detector unit of the optical receiving unit is calibrated. As an alternative or in addition to the step in which the detector unit is calibrated, a step can include determining the laser power based on the redirected laser line. Optionally, separate steps following the step in which the orientation of the laser line is determined may include determining eye safety based on the redirected laser line and monitoring individual laser diodes based on the redirected laser line or functional safety of the optical scanning system.

[0005] The invention is based on the object of designing a method, a detection device and a vehicle of the above mentioned type, with improved functional safety of the detection device. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] DE 102017223618 Summary of the Invention

[0007] The present invention relates to the duration of each transmission of the optical signal is limited to a specified transmission time interval to achieve eye safety of the detection device; The eye safety of the detection device by configuring at least one of the receiving areas as a measurement receiving area and configuring at least one of the receiving areas as a test receiving area; by generating at least one measurement reception variable characterizing an amount of light captured using at least one measurement reception area in at least one measurement time interval; by generating at least one test reception variable characterizing an amount of light captured using at least one test receiving area during at least one test time interval; at least one test time interval is longer than at least one measurement time interval, at least one test time interval is longer than the transmission time interval; A fault condition is generated if at least one test receiving variable characterizes an amount of light that is greater outside the specified tolerance variables than an amount of light characterized using at least one measured receiving variable. In this respect, the method achieves this objective.

[0008] According to the invention, eye safety for the detection device is achieved by limiting the transmission of the optical signal. For this purpose, the duration of the transmission of the optical signal is limited to a specified transmission time interval in each case. For an optical signal transmitted for the duration of the transmission time interval, the longer the transmission time interval, the higher the amount of light transmitted. By limiting the amount of light transmitted for the transmission time interval, eye safety for the detection device is achieved. The transmission time interval is specified in such a way that eye safety is ensured to be achieved, in particular based on the type of optical signal transmitted.

[0009] Eye safety of a detection device within the meaning of the present invention is a function and / or property of the detection device which ensures that in particular legally prescribed eye safety limits are observed when operating the detection device. Eye safety is the functional safety of the detection device.

[0010] Advantageously, limiting the duration of the transmission of the optical signal using at least one safety means can in particular be performed by software and / or by hardware.

[0011] Advantageously, at least one transmission time interval can be specified such that the transmission of the optical signal is significantly below the eye safety limits, thereby ensuring that the eye safety limits are safely observed.

[0012] The receiving area of ​​the at least one receiver is used to receive reflected light signals, which may be called echo signals, and convert them into receiving variables. Advantageously, the receiving area can be used to receive light signals from the at least one monitoring area, in particular reflected by objects. The receiving variables can be used to determine information about the monitoring area, in particular object information, such as the distance, speed and / or direction of the object relative to the detection device.

[0013] Furthermore, at least one reception variable can be obtained as a basis for checking the eye safety of the detection device. This can include using a reception variable derived from an echo signal coming from at least one monitoring area. Alternatively or additionally, a reception variable from an optical signal reflected in the detection device can be used.

[0014] In particular, a malfunction of at least one safety means may lead to the optical signal still being transmitted after the end of the transmission time interval, which may result in eye safety being compromised.

[0015] To test the eye safety of the detection device, in particular the function of the at least one safety measure, the reflected light signal is received using at least two receiving areas, namely at least one measurement receiving area and at least one test receiving area, and converted into a respective reception variable. The reflected light signal is captured using at least one measurement receiving area for the duration of at least one measurement time interval. At least one test receiving area is used to capture the light signal for the duration of at least one test time interval.

[0016] The at least one test time interval is longer than the transmission time interval. In this manner, the at least one test receiving area can be used to capture optical signals transmitted using the at least one light emitting element beyond the end of the at least one measurement time interval.

[0017] The at least one test time interval is longer than the at least one measurement time interval and the transmission time interval, such that the at least one test receiving area can be used to receive and convert optical signals for a longer period of time than the at least one measurement receiving area.

[0018] In this way, the at least one measurement receiving area and the at least one measurement time interval can be used to characterize a target state for the emission on the assumption that the eye safety, in particular the safety means, is functional, and the at least one test receiving area and the at least one test time interval can be used to characterize an actual state for the emission for the eye safety, in particular for the at least one safety means.

[0019] If the amount of light characterized using the at least one test reception variable is greater than the amount of light characterized using the at least one measured reception variable outside of a specified tolerance limit, i.e., if the actual state of the light emission deviates from the target state outside of a tolerance limit, it is concluded that the at least one test reception area continues to capture echo signals derived from the light signal transmitted using the at least one light emitting element during the period between the end of the at least one measurement time interval and the end of the at least one test time interval. From this, it is concluded that there is an error in the limit of the transmission of the light signal. Then, a fault condition is generated so as not to jeopardize the eye safety of the detection device.

[0020] A tolerance limit for the comparison of the test and measured receiving variables can be advantageously specified, in particular at the end of the production line. The tolerance limit can advantageously be zero.

[0021] The measurement receiving area and the test receiving area can advantageously be of the same type of receiving area: in order to check the eye safety, in particular the functioning of the at least one safety means, some of the receiving areas can be configured as measurement receiving areas and other instances of the receiving areas can be configured as test receiving areas.

[0022] Advantageously, the at least one light emitting element can be used to transmit an optical signal, in particular in the form of a pulsed laser signal, which can be generated simply and precisely.

[0023] Advantageously, the detection device can operate according to the signal time-of-flight method, in particular the signal pulse time-of-flight method. Detection devices operating according to the signal pulse time-of-flight method can be designed and referred to as Time-of-Flight (TOF) systems, Light Detection and Ranging (LiDAR) systems, Laser Detection and Ranging (LaDAR) systems, etc.

[0024] Advantageously, the detection device can be designed as a scanning system. In this context, the monitored area can be sampled, i.e. scanned, using the optical signal. For this purpose, the propagation direction of the optical signal can be changed, in particular swiveled, on the monitored area. This can involve using at least one signal deflection device, in particular a scanning device, a deflection mirror device, etc. Alternatively, the detection device can be designed as a so-called flash system, in particular a flash LiDAR. A suitably diffused optical signal can simultaneously illuminate a relatively large part of the monitored area or the entire monitored area.

[0025] Advantageously, the detection device can be designed as a laser-based distance measuring system. The laser-based distance measuring system can include a laser, in particular a diode laser, as a signal source. The laser can be used in particular to transmit a pulsed laser signal. The laser can be used to emit an optical signal in a wavelength range that is visible or invisible to the human eye. The receiver of the detection device can therefore comprise or consist of a sensor, in particular a point sensor, a line sensor and / or an area sensor, in particular an (avalanche) photodiode, a photodiode line, a CCD sensor, an active pixel sensor, in particular a CMOS sensor, etc., which is designed for the wavelength of the transmitted optical signal. The laser-based distance measuring system can be advantageously designed as a laser scanner. The laser scanner can be used to scan the monitoring area in particular with a pulsed laser signal, in particular with a laser beam.

[0026] The present invention can be advantageously used in vehicles, especially automobiles. The present invention can be advantageously used in land vehicles, especially cars, trucks, buses, motorcycles, etc., aircraft, especially drones, and / or ships. The present invention can also be used in vehicles that can operate autonomously or at least semi-autonomously. However, the present invention is not limited to vehicles. The present invention can also be used in stationary motion, robotics and / or machines, especially construction or transport machines such as cranes, excavators, etc.

[0027] The detection device may advantageously be connected to or be part of at least one electronic control device of the vehicle or machine, in particular a driver assistance system and / or a chassis control system and / or a driver information device and / or a parking assistance system and / or a gesture recognition system, etc. In this way, at least some of the functions of the vehicle or machine can be performed autonomously or semi-autonomously.

[0028] The detection device can be used to detect stationary or moving objects, in particular vehicles, people, animals, plants, obstacles, road irregularities, in particular potholes or rocks, road boundaries, traffic signs, open spaces, in particular parking spaces, rainfall, etc., and / or movements and / or gestures.

[0029] In one advantageous configuration of the method, At least one measurement time interval and / or at least one test time interval and / or transmission time interval may be implemented to at least partially overlap in time, and / or at least one measurement time interval and / or at least one test time interval and / or transmission time interval can start simultaneously. In this way, at least one measurement reception area and at least one test reception area can be used to at least intermittently receive the same optical signal. This allows the respective determined reception variables to be compared with each other more effectively. Furthermore, the measurement reception variables and the test reception variables can be determined simultaneously in a time-saving manner.

[0030] By starting the time intervals at the same time, it is possible to avoid gaps, which allows a more effective comparison of the measured and test received variables.

[0031] Alternatively or additionally, the at least one measurement time interval and the at least one test time interval may start consecutively without overlapping, in this way the determination of the measurement reception variable and the determination of the test reception variable may be performed consecutively.

[0032] In a further advantageous configuration of the method, At least one test reception variable and at least one measurement reception variable of spatially adjacent reception regions can be determined; and / or determining a respective measurement reception variable of at least two spatially adjacent measurement reception areas; and / or a test reception variable for each of at least two spatially adjacent test reception areas can be determined, in this way the same optical signal can be received using the receiving areas involved, which makes it possible to further improve the comparability of the determined reception variables.

[0033] Advantageously, a respective measured reception variable of at least two spatially adjacent measurement receiving areas can be determined. Alternatively or additionally, a respective test reception variable of at least two spatially adjacent test receiving areas can be determined. In this way, a spatial resolution can be further obtained when capturing the optical signal. This makes it possible to determine, in particular, in the direction from which the optical signal comes. Advantageously, the plurality of measurement receiving areas and / or the plurality of test receiving areas can be arranged in a matrix format and / or in rows.

[0034] In a further advantageous configuration of the method, At least one measurement time interval may be specified as having approximately the same length as a transmission time interval; And / or the at least one measurement time interval can be specified as having a length not greater than the at least one transmission time interval. In this way, the target state with respect to the light emission can be more accurately characterized using the at least one measurement receiving area, based on the assumption that the eye safety is functional, in particular that the at least one safety means is functional.

[0035] Advantageously, at least one measurement time interval can be specified as having a length not greater than at least one transmission time interval, in this way at least one measurement receiving area can be used during at least one measurement time interval to capture a maximum amount of light transmitted during a transmission time interval using at least one light emitting element when eye safety is active, in particular when the safety means is active.

[0036] In a further advantageous configuration of the method, At least one eye safety test is performed during normal operation of the detection device; And / or at least one eye safety test is performed outside of normal operation of the detection device.

[0037] When checking eye safety during normal operation, the safety stops may be checked more frequently.

[0038] When testing eye safety outside of normal operation, all receiving areas may be used as measurement receiving areas instead during normal operation.

[0039] Advantageously, an eye safety check can be performed after the detection device is switched on, in this way malfunctions can be detected before normal operation begins.

[0040] In a further advantageous configuration of the method, at least one light emitting element can be used for transmitting a modulated light signal, in this way information about at least one monitoring area, in particular the distance, speed and / or direction of detected objects in the monitoring area, can be determined more effectively, in particular more easily and / or more accurately.

[0041] Advantageously, the modulated light signal can be transmitted in the form of light pulses. In this way, the detection device can operate in particular according to the time-of-flight method. Alternatively or additionally, the modulated light signal can be transmitted as a continuous wave signal.

[0042] Advantageously, the at least one photoelectric element can be activated to transmit an optical signal, in particular by an electrical trigger signal, which can be generated using suitable means of the detection device, in particular the control device and / or the driver device.

[0043] In a further advantageous configuration of the method, the fault condition generated may be the stopping of at least one photoelectric element, at least one error signal, at least one visual, audible and / or tactile output signal, or the like.

[0044] By deactivating at least one photoelectric element it is possible to ensure further transmission of the optical signal.

[0045] The error signal can be used to output information regarding an erroneous state of the detection device, in particular regarding the eye safety of the detection device. The error signal can in particular be processed automatically.

[0046] A visual, audible and / or tactile output signal may be used to directly notify a user of the detection device and / or maintenance personnel for the detection device of the presence of a fault.

[0047] Furthermore, the present invention relates to a method for producing a The detection device has at least one safety means for limiting the duration of the transmission of the optical signal to a specified transmission time interval in order to achieve eye safety, and at least one inspection device for the at least one safety means; The inspection device means for configuring at least one receiving area as a measurement receiving area for the purpose of generating, from at least one received optical signal, at least one measurement receiving variable characterizing an amount of light that can be captured using the at least one measurement receiving area in at least one measurement time interval; means for configuring at least one receiving area as a test receiving area for the purpose of generating at least one test receiving variable characterizing an amount of light that can be captured using the at least one test receiving area in at least one test time interval from at least one received optical signal; means for evaluating at least some of the received variables; means for generating at least one fault condition when at least one test reception variable characterizes an amount of light that is greater outside the tolerance variables than an amount of light characterized using at least one measured reception variable; have In this respect, the present detection device achieves its object.

[0048] According to the invention, the detection device has at least one inspection device for inspecting at least one safety means for limiting the transmission of the light signal. The inspection device can be used to inspect whether the at least one safety means is functioning correctly. The function of the at least one safety means is to limit the duration of the transmission of the light signal. In this way, eye safety can be achieved using the at least one safety means. Thus, the at least one inspection device can be used to inspect the eye safety of the detection device.

[0049] The at least one inspection device can be used to determine if the at least one safety means does not stop transmitting the light signal after a specified transmission time interval due to a malfunction. In this case, a fault condition can be generated using the means of the inspection device. The fault condition can include suitable means. In particular, the at least one light-emitting element can be stopped. Alternatively or additionally, at least one error signal and / or at least one visual, audible and / or tactile output signal can be generated.

[0050] In one advantageous embodiment, At least one measurement receiving area and at least one test receiving area may be formed from the same type of receiving area; And / or, the at least one measurement receiving area and / or the at least one test receiving area may be separately configurable to record receiving variables at different time intervals.

[0051] At least one measurement receiving area and / or at least one test receiving area may be formed from the same type of receiving area, thus at least one receiver receiving area can be configured as either a measurement receiving area or a test receiving area.

[0052] Alternatively or additionally, the at least one measurement receiving area and / or the at least one test receiving area may be separately operable to record the receiving variables at different time intervals. In this way, the measurement receiving area and the test receiving area can be activated for different time intervals.

[0053] In a further advantageous embodiment, The at least one receiver may have multiple point sensors, at least one line sensor, and / or at least one area sensor used to generate a respective reception area.

[0054] A point sensor is used to implement a specific reception area. The use of multiple point sensors makes it possible to generate multiple reception areas. The point sensor may in particular be a photodiode or the like.

[0055] In the case of a line sensor, multiple receiving areas are arranged in a row. Line sensors can be made more compact and / or more easily read than single point sensors arranged next to each other. Line sensors can advantageously be realized as rows of diode linear arrays or area sensors, in particular CCD sensors, active pixel sensors, etc.

[0056] In the case of an area sensor, a number of receiving areas are arranged in two dimensions, in particular in the form of a matrix. The area sensor can advantageously be realized as a CCD sensor, an active pixel sensor or the like.

[0057] Additionally, line and area sensors can also be used for spatially resolved measurements.

[0058] Furthermore, the present invention relates to a method for producing a The detection device has at least one safety means for limiting the duration of the transmission of the optical signal to a specified transmission time interval in order to achieve eye safety, and at least one inspection device for the at least one safety means; The inspection device, means for configuring at least one receiving area as a measurement receiving area for the purpose of generating, from at least one received optical signal, at least one measurement receiving variable characterizing an amount of light that can be captured using the at least one measurement receiving area in at least one measurement time interval; means for configuring at least one receiving area as a test receiving area for the purpose of generating at least one test receiving variable characterizing an amount of light that can be captured using the at least one test receiving area in at least one test time interval from at least one received optical signal; means for evaluating at least some of the received variables; means for generating at least one fault condition when at least one test reception variable characterizes an amount of light that is greater outside the tolerance variables than an amount of light characterized using at least one measured reception variable; have In this respect, the vehicle achieves its intended purpose.

[0059] According to the invention, the vehicle comprises at least one detection device complying with eye safety limits, which can be used to monitor at least one monitoring area outside the vehicle and / or inside the vehicle, in particular for objects.

[0060] In an advantageous embodiment, the vehicle may comprise at least one driver assistance system, which may be used to operate the vehicle autonomously or semi-autonomously.

[0061] Advantageously, the at least one detection device can be functionally connected to at least one driver assistance system, such that information about the monitoring area, in particular object information determined using the at least one detection device, can be used in the at least one driver assistance system for controlling the autonomous or semi-autonomous operation of the vehicle.

[0062] Furthermore, the features and advantages given in relation to the method according to the invention, the detection device according to the invention and the vehicle according to the invention, as well as their respective advantageous configurations, apply in a mutually corresponding manner and vice versa, and the individual features and advantages can of course be combined with one another, resulting in further advantageous effects that exceed the sum of the individual effects.

[0063] Further advantages, features and details of the invention will become apparent from the following description in which exemplary embodiments of the invention are described in more detail with reference to the drawings. A person skilled in the art will also conveniently consider individually the features disclosed in combination in the drawings, the specification and the claims and combine them to form further meaningful combinations. [Brief description of the drawings]

[0064] [Figure 1] FIG. 1 shows a front view of a vehicle having a driver assistance system and a LiDAR system for detecting objects in the direction of travel ahead of the vehicle. [Diagram 2] FIG. 2 shows a functional diagram of a vehicle having the driver assistance system and the LiDAR system of FIG. 1. [Diagram 3] FIG. 3 shows a plan view of a detail from a receiver of the LiDAR system of FIGS. 1 and 2 having multiple receiving areas arranged in two dimensions. [Figure 4] From top to bottom, time characteristics of a trigger input signal, a trigger output signal for controlling the laser of the LiDAR system of Figures 1 and 2, a measurement integral signal for activating the measurement receiving area of ​​the receiver of Figure 3, and a test integral signal for activating the test receiving area of ​​the receiver are shown, and a safety means of the LiDAR system is used to terminate the transmission of the laser signal using the laser after a transmission time interval. [Diagram 5] Along the columns including the receiving areas of the receiver of FIG. 3 , a strength / receiving area graph of the receiving variable is shown generated from the laser echo signal integrated over the integration time of the respective receiving area, the receiving areas are alternately operated as measurement receiving areas and test receiving areas using the respective integrated signals, and a safety means of the LiDAR system is used to terminate the transmission of the laser signal using the laser after the transmission time interval. [Figure 6] From top to bottom, the same time characteristics as in FIG. 4 are shown, in which the transmission of the transmission signal using the laser is not terminated after the transmission time interval. [Figure 7]5 shows a graph of the intensity / reception area of ​​the reception variable, similar to FIG. 5, where the transmission of the transmission signal using the laser is not terminated after the transmission time interval. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0065] In the drawings, identical elements are marked with identical reference numbers.

[0066] FIG. 1 shows a front view of a vehicle 10, for example in the form of a passenger car.

[0067] The vehicle 10 comprises an optical detection device, for example in the form of a LiDAR system 12. The LiDAR system 12 is designed as a laser scanner. For example, the LiDAR system 12 can be a Near-Field Laser Scanner (NFL). Figure 2 shows a functional diagram of the vehicle 10 with the LiDAR system 12.

[0068] As an example, the LiDAR system 12 is disposed on a front fender of the vehicle 10. The LiDAR system 12 can be used to monitor a surveillance area 14 in a direction of travel 16 ahead of the vehicle 10 for objects 18. The LiDAR system 12 can also be disposed at other points on the vehicle 10 and oriented differently. The LiDAR system 12 can also be disposed on the vehicle 10 for interior monitoring. The LiDAR system 12 can be used to determine object information, such as the distance, direction and speed of the object 18 relative to the vehicle 10 or the LiDAR system 12, respectively, or corresponding characteristic variables.

[0069] The objects 18 can be stationary or moving objects, such as other vehicles, people, animals, plants, obstacles, road irregularities, such as potholes or rocks, road boundaries, traffic signs, open spaces, such as parking spaces, rainfall, etc. Human gestures can also be detected using the LiDAR system 12.

[0070] The LiDAR system 12 is connected to a driver assistance system 20 of the vehicle 10. The driver assistance system 20 can be used to operate the vehicle 10 autonomously or semi-autonomously.

[0071] The LiDAR system 12 comprises, for example, a sensor unit 22, for example in the form of an NFL sensor, and a control unit 24. The sensor unit 22 is connected to the control unit 24 via an interface 26, for example a Low Voltage Differential Signaling (LVDS) interface, for example FPD-Link III. To generate the interface 26, the sensor unit 22 comprises a serializer 28 and the control unit 24 comprises a deserializer 30.

[0072] The sensor unit 22 includes a transmitting device 32, a receiving device 34, a driver and safety device 36, and a serializer 28.

[0073] The control unit 24 comprises a control and evaluation device 38 and a deserializer 30 .

[0074] The interface 26 can be used to transfer data from the receiving device 34 to the control and evaluation device 38. Furthermore, the interface 26 has a return channel. The return channel is, for example, 2 It may be used by the control and evaluation device 38 to communicate with the receiving device 34 using the C protocol.

[0075] The transmitting device 32 has as a signal source, for example, a laser 40, for example a diode laser. The laser 40 can be used for transmitting, for example, a pulsed laser signal 42. The transmitting device 32 can optionally have at least one optical system, for example at least one optical lens, which can be used to influence, for example diffuse and / or focus, the generated laser signal 42, as required. The LiDAR system 12 can be designed as a scanning LiDAR system or a flash LiDAR system.

[0076] Furthermore, the transmitting device 32 may optionally comprise a signal deflection device that may be used to direct the laser signal 42 into the monitored area 14. The signal deflection device may be changeable, e.g., rotatable. In this way, the propagation direction of the laser signal 42 may be steered and the monitored area 14 may be sampled or scanned.

[0077] The transmitting device 32 is connected to the driver and safety device 36 via a control connection 44. The control connection 44 can be used to activate the laser 40 with a trigger output signal 46 from the driver and safety device 36 to transmit a laser signal 42. Figure 4 shows an example of details from the trigger output signal 46 over time.

[0078] The driver and safety device 36 is connected to the receiving device 34 via a signal connection 48. The signal connection 48 can be used to send a trigger input signal 50 from the receiving device 34 to the driver and safety device 36. Figure 4 shows an example of details from the trigger input signal 50 over time.

[0079] The driver and safety device 36 has a disconnectable connection between the signal connection 48 and the control connection 44 that can be used to transfer trigger input signals 50 from the signal connection 48 to the control connection 44 and send them to the sending device 32 as trigger output signals 46.

[0080] The driver and safety device 36 comprises a safety means 47 which can be used to interrupt the connection between the signal connection 48 and the control connection 44. The safety means 47 can be used, for example, to limit the transmission of the laser signal 42 to a specified transmission time interval TS. The transmission time interval TS is specified such that the transmitted optical signal 42 is below eye safety limits. Thus, eye safety can be achieved when operating the LiDAR system 12.

[0081] The receiving device 34 comprises a receiver 52 and electronic components for controlling the receiver 52 and for generating a receiving variable 54. The receiver 52 and the electronic components can for example be realized as an image sensor as a "system on chip", a so-called imager. Furthermore, the receiving device 34 comprises signal generating means which can be used to generate a trigger input signal 50.

[0082] The receiver 52 is realized as an area sensor, for example in the form of a CCD array. Alternatively, an active pixel sensor, a linear array of multiple photodiodes, etc. may be provided. Details from the receiver 52 are shown in plan view in Figure 3. The receiver 52 has a number of receiving areas 56 arranged adjacent to one another in a number of rows 58. The receiving areas 56 may also be referred to as "pixels".

[0083] The receiving area 56 can be used to convert an optical signal, such as an echo signal 60 from the laser signal 42 reflected by an object 18 in the monitored area 14, into a corresponding electrical receive signal. The receive signal can be used to generate a receive variable 54. The receive variable 54 can be used to characterize the receive echo signal 60, such as its amount of light or light energy.

[0084] The receiving areas 56 may be activated for different time intervals TE during which the respective receiving variables 54 may be generated from the incoming echo signals 60. The time intervals TE may also be referred to as "integration times." As an example, receiving areas 56 located in the same row 58 may be activated for the same time intervals TE.

[0085] The receiving device 34 may optionally have at its optical input side an echo signal deflection device and / or an optical system, for example an optical lens, that can be used to direct the echo signal 60 to the receiver 52 .

[0086] The receiving device 34 is connected to a control and evaluation device 38 by an interface 26 which includes a serializer 28 and a deserializer 30 .

[0087] The control and evaluation device 38 can be used to process the received variables 54 generated using the receiving device 34. For example, the control and evaluation device 38 can be used to obtain the received variables 54 and determine therefrom object variables, e.g. distance variables, direction variables and / or speed variables that characterize the distance, direction and / or speed of the detected object 18 relative to the LiDAR system 12 or relative to the vehicle 10.

[0088] Furthermore, the control and evaluation device 38 may be, for example, 2 The receiver 52 may be configured using the C protocol. For example, the receiving area 56 may be activated with an appropriate integrating signal 64 for each time interval TE. The integrating signal 64 may be, for example, a square wave pulse having a length of the applicable time interval TE. The rising edge of the square wave pulse of the integrating signal 64 may be used to initiate the respective time interval TE and activate the applicable receiving area 56 to capture the echo signal 60 for the duration of the square wave pulse.

[0089] Furthermore, the control and evaluation device 38 can be used to configure the driver and safety device 36. For example, the length of the transmission time interval TS during which the laser 40 is used to transmit the laser signal 42 can be specified. Furthermore, the control and evaluation device 38 can be used to start the transmission time interval TS. The transmission time interval TS and the time interval TE of the reception area 56 can be started in a coordinated manner, for example simultaneously.

[0090] Furthermore, the control and evaluation device 38 comprises a safety stop test means 62 which can be used to test the function of the safety means 47 of the driver and safety device 36 and to prevent further transmission of the laser signal 42 if a malfunction is detected.

[0091] For this purpose, the safety stop test means 62 is provided with a test time interval TE T Test integral signal 64 for activation during T Some of the receiving areas 56 are test receiving areas 56 T Another example of the receiving area 56 can be used to check the function of the safety means 47 by operating it as a measuring time interval TE M 64 Measuring integral signal for activation during M By measuring the receiving area 56 M It can be operated as.

[0092] Measurement time interval TE M is, for example, slightly shorter than the transmission time interval TS. The test time interval is the measurement time interval TE M and longer than the transmission time interval TS. T is specified such that the LiDAR system 12 operates below the eye safety limit.

[0093] Furthermore, the safety stop test means 62 is connected to the test receiving area 56 T Test receiving variables determined during inspection by 54 T A, measuring receiving area 56 M Measurement receiving variables determined by 54 M can be used to compare with the test receiving variable 54 T However, the measurement receiving variable 54 M A fault condition may be generated using the fault condition control means 63 of the safety stop testing means 62 when an amount of light in the received echo signal 60 is characterized that is greater than an amount of light in the received echo signal 60 characterized using the fault condition control means 63. For example, the fault condition control means 63 may be used to interrupt the connection between the signal connection 48 and the control connection 44 of the driver and safety device 36 as a fault condition.

[0094] The functions and components of the control and evaluation device 38 and the driver and safety devices 36 may be implemented centrally or locally. Some of the functions and components of the control and evaluation device 38 and the driver and safety devices 36 may also be integrated in the sending device 32 and / or the receiving device 34. The control and evaluation device 38, the driver and safety devices 36 and the driver assistance system 20 may also be partially combined. The functions of the control and evaluation device 38 and the driver and safety devices 36 are implemented by software and hardware.

[0095] A method for operating the LiDAR system 12 is described in more detail below. First, a normal operation for monitoring the monitoring area 14, then a test mode for testing the safety measures 47 of the driver and safety device 36 is described.

[0096] During normal operation, the control and evaluation device 38 is used to configure the receiving device 34 and initiate measurements. M and the same measurement integral signal 64 specified by the control and evaluation device 38 as M The measurement receiving area 56 M is the same measurement time interval TE for receiving the echo signal 60. M is activated over

[0097] The receiving device 34 receives the measurement time interval TE M , for a duration of measurement time interval TE. The driver and safety device 36 transmits the trigger input signal 50 as a trigger output signal 46 to the transmitting device 32 via the control connection 44. In response to the trigger output signal 46, the laser 40 transmits a trigger input signal 50 to the transmitting device 32 over the control connection 44 for a duration of measurement time interval TE. M is used to transmit a pulsed laser signal 42 into the monitored area 14 for a duration of .

[0098] Measurement integral signal 64 MWhen the start of the transmission time interval TS begins, the driver and safety device 36 is further used to start a specified transmission time interval TS. After the transmission time interval TS has elapsed, the safety means 47 is used to interrupt the connection between the signal connection 48 and the control connection 44, so that no further trigger output signals 46 are transmitted to the transmitting device 32. Thus, the transmission of the laser signal 42 is terminated. This allows, for example, a measurement integral signal 64 M When transmitting, exceeding eye safety limits is prevented in the event of a malfunction.

[0099] The transmitted laser signal 42 is reflected, for example, by objects 18 in the monitored area 14 in the direction of the LiDAR system 12. M During this time, the reflected laser signal 42 is received as an echo signal 60 using a measurement receiving area 56, and a respective receiving variable 54 M is generated.

[0100] Receiving variable 54 M is transmitted to the control and evaluation device 38, which is located within the reception area 56 of the receiver 52. M 5 shows, by way of example, a section of the amplitude image 66 along a column perpendicular to the rows 58 of the receivers 52.

[0101] Furthermore, the control and evaluation device 38 can be used to receive variables 54 M from which object variables, e.g. the reception area 56 for or respectively the LiDAR system 12 are obtained. M Distance, direction and / or velocity variables characterizing the distance, direction and / or velocity of the detected object 18 relative to the target object 18 may be determined.

[0102] The determined object variables are transmitted to a driver assistance system 20. The driver assistance system 20 is used to operate the vehicle 10 autonomously or semi-autonomously using the object variables.

[0103] In a test mode for testing the safety means 47 using the safety stop test means 62, the control and evaluation device 38 is used to configure the receiving device 34 as required and to start measurements. M some of the receiving areas 56 are configured as test receiving areas 56 T For example, the row 58 including the receiving area 56 is configured as the measurement receiving area 56. M and test receiving area 56 T The measurement receiving area 56 is alternately configured as M is the same measurement integral signal 64 specified by the control and evaluation device 38. M The measurement receiving area 56 M is the same measurement time interval TE for receiving the echo signal 60. M The test reception area 56 T is the same test integral signal 64 specified by the control and evaluation device 38. T Test reception area 56 T is the same test time interval TE T The echo signal 60 is ready to be received over a measurement time interval TE M is the test time interval TE T Starts at the same time.

[0104] The receiving device 34 receives the measurement time interval TE M , for a duration of measurement time interval TE. The driver and safety device 36 forwards the trigger input signal 50 to the transmitting device 32 as a trigger output signal 46. In response to the trigger output signal 46, the laser 40 transmits a trigger M is used to transmit a pulsed laser signal 42 into the monitored area 14 for a duration of .

[0105] Measurement integral signal 64 M When the transmission time interval TS starts, the driver and safety device 36 is further used to start a specified transmission time interval TS.

[0106] If the driver and safety device 36 is functioning correctly, the connection between the signal connection 48 and the control connection 44 is interrupted after the transmission time interval TS has elapsed, as in normal operation, so that the trigger output signal 46 is no longer transmitted to the transmitting device 32. The transmission of the laser signal 42 is therefore terminated. The signal characteristics for this situation are shown in FIG.

[0107] Illuminated measuring receiving area 56 M is the measurement time interval TE M During the monitoring period, the laser signal 42 reflected by the object 18 in the monitoring area 14 in the direction of the LiDAR system 12 is received as an echo signal 60, and the respective measured received variable 54 is measured. M Further, the echo signal 60 is generated during the test time interval TE T Test reception area 56 illuminated during T Each test is received using 54 T is generated.

[0108] Measurement receiving variables 54 M and test reception variable 54 T is transmitted to the control and evaluation device 38, which is connected to the measurement reception area 56 of the receiver 52. M and test receiving area 56 T 5 shows, as an example, a section of the amplitude image 66 along a column perpendicular to the rows 58 of the receivers 52, during which the driver and safety devices 36 are functioning properly.

[0109] As shown in FIG. 4, the transmission time interval TS is M Therefore, the trigger output signal 46 is generated at the measurement time interval TE M , is used to activate the laser 40 for a further period of the trigger output signal 46 to transmit the laser signal 42 after the end of the measurement time interval TE. Thus, the trailing portion of the associated echo signal 60 is M It is not active outside the measurement reception area 56M However, the later portion of the echo signal 60 is not received within the test time interval TE T Test reception area 56 T As a result, the test reception area 56 T The measurement reception area is 56 M 42. The applicable measurement reception area 56 is therefore exposed to the echo signal 60 of the laser signal 42 for a slightly longer period of time than the M 54, a measurement reception variable that characterizes the amount of light received using M 5, each adjacent test receiving area 56 T Each test received using the received variables 54 T The adjacent measurement receiving area 56 is slightly smaller than M Measurement of receiving variables 54 M and test receiving area 56 T Test reception variables 54 T The intensity difference between adjacent test receiving variables 54 is within a specified tolerance limit, for example. T and 54 measured receiving variables M are compared to one another. Because the intensity difference is within acceptable limits, no fault condition is generated using the safety shutdown test means 62.

[0110] If the driver and safety device 36 or the safety means 47 are not functioning correctly, it may happen that the connection between the signal connection 48 and the control connection 44 is not interrupted after the transmission time interval TS has elapsed. The trigger output signal 46 is therefore still transmitted to the transmitting device 32. The transmission of the light signal 42 continues after the transmission time interval TS has elapsed. The signal characteristics of this situation are shown in Figure 6. If the light signal 42 is transmitted for a relatively long time, eye safety is threatened.

[0111] As in fault-free operation, the laser signal 42 reflected by the object 18 in the monitored area 14 towards the LiDAR system 12 is measured over a measurement time interval TE M Between each measurement receiving area 56 M and a corresponding measured receive variable 54M Further, the echo signal 60 is generated during the test time interval TE T Between each test receiving area 56 T Received using the corresponding test reception variable 54 T is generated.

[0112] Measured receiving variables 54 as well as fault-free operation of the driver and safety devices 36 M and test reception variable 54 T are transmitted to the control and evaluation device 38, which is used to determine an amplitude image 66 characterizing the intensity characteristics of the echo signal 60 along the receiving area 56 of the receiver 52. Figure 7 shows, similar to Figure 5, a section of the amplitude image 66 along a column perpendicular to the rows 58 of the receiver 52, where the driver and safety device 36 is not functioning correctly.

[0113] 6, a malfunction means that the trigger output signal 46 continues after the end of the transmission time interval TS, and the laser 40 is still activated to transmit the laser signal 42. M After the end of the measurement, the trailing portion of the echo signal 60 of the continued laser signal 42 is reflected by the measurement receiving area 56. M However, the later portion of the echo signal 60 is not received within the test time interval TE T Until the end of the test reception area 56 T As a result, the test reception area 56 T The measurement reception area is 56 M The measurement receiving area 56 is exposed to the laser signal 42 for a period of time much longer than the M Measurement of receiving variables 54 M 7, compared to fault-free operation as shown in FIG. 5, for each adjacent test reception area 56 T Test reception variables 54 T is significantly smaller than

[0114] Adjacent test receiving variables 54 T and 54 measured receiving variables Mare compared with each other. M Measurement of receiving variables 54 M and test receiving area 56 T Test reception variables 54 T Since the intensity difference between is outside specified tolerance limits, a malfunction of the safety means 47 is assumed. The safety stop test means 62 is used to generate a fault condition in the form of an interruption to the connection between the control connection 44 and the signal connection 48 of the driver and safety device 36.

Claims

1. A method for operating an optical detection device (12) arranged to monitor at least one monitoring area (14), comprising the steps of: At least one light emitting element (40) is activated to transmit at least one optical signal (42); At least one reflected optical signal (60) is received using at least two receiving areas (56) of at least one receiver (52); determining at least one received variable (54) using the at least one received optical signal (42); A method, in which the functional safety of the optical detection device (12) is checked at least intermittently, the duration of the transmission of each of the optical signals (42) is limited to a designated transmission time interval (TS) to achieve eye safety of the optical detection device (12); The eye safety of the optical detection device (12) At least one of the receiving areas (56) is a measurement receiving area (56) Ｍ ), and at least one of the receiving areas (56) is configured as a test receiving area (56). Ｔ ), At least one measurement time interval (TE Ｍ At least one measurement receiving area (56) Ｍ ) to characterize the amount of captured light. Ｍ ), At least one test time interval (TE Ｔ At least one test receiving area (56) Ｔ At least one test reception variable (54) characterizing the amount of captured light using Ｔ ), The at least one test time interval (TE Ｔ ) is the at least one measurement time interval (TE Ｍ ) and the at least one test time interval (TE Ｔ ) is longer than the transmission time interval (TS), At least one test receiving variable (54 Ｔ ) at least one measured received variable (54 Ｍ a fault condition is generated if the amount of light characterized using the threshold is greater than the amount of light characterized using the threshold outside a specified tolerance variable.

2. At least one measurement time interval (TE Ｍ ) and / or at least one test time interval (TE Ｔ ) and / or transmission time intervals (TS) are implemented to at least partially overlap in time, and / or at least one measurement time interval (TE Ｍ ) and / or at least one test time interval (TE Ｔ ) and / or the transmission time interval (TS) start at the same time.

2. The method according to claim 1 .

3. At least one test reception variable (54) in a spatially adjacent reception area (56) Ｔ ) and at least one measured receiving variable (54 Ｍ ) is determined, and / or at least two spatially adjacent measurement receiving areas (56 Ｍ ) each measured receiving variable (54 Ｍ ) is determined, and / or at least two spatially adjacent test receiving areas (56 Ｔ ) each test receiving variable (54 Ｔ ) is determined.

2. The method according to claim 1 .

4. The at least one measurement time interval (TE Ｍ ) is specified as having approximately the same length as the transmission time interval (TS); and / or said at least one measurement time interval (TE Ｍ ) is specified as having a length not greater than at least one transmission time interval (TS).

2. The method according to claim 1 .

5. at least one eye-safety test is performed during normal operation of the optical detection device (12); and / or at least one eye-safety test is performed outside of normal operation of the optical detection device (12).

2. The method according to claim 1 .

6. 2. The method of claim 1, wherein at least one light emitting element (40) is used to transmit a modulated optical signal (42).

7. The fault condition generated is Deactivation of at least one photoelectric element; At least one error signal, or at least one visual, audio and / or tactile output signal; The method of claim 1 , characterized in that the method is at least one of:

8. An optical detection device (12) for monitoring at least one monitoring area (14), comprising: having at least one light emitting element (40) for transmitting an optical signal (42); having at least two receiving areas (56) for receiving the reflected optical signal (42); at least one means (52) for determining a received variable (54) from the received optical signal (42); at least one means (38) for controlling said optical detection device (12) and for processing received variables (54); at least one means (62, 63) for checking the functional safety of the optical detection device (12), In the optical detection device (12), said optical detection device (12) having at least one safety means (36, 47) for limiting the duration of said transmission of an optical signal (42) to a specified transmission time interval (TS) in order to achieve eye safety, and at least one inspection device (38, 62, 63) for said at least one safety means (36, 47), The inspection device (38, 62, 63), At least one measurement time interval (TE) is determined from at least one received optical signal (42). Ｍ At least one measurement receiving area (56) Ｍ At least one measured reception variable (54) characterizing the amount of light that can be captured using the Ｍ At least one receiving area (56) is measured to generate a receiving area (56). Ｍ ) and At least one test time interval (TE) is detected from at least one received optical signal (42). Ｔ At least one test receiving area (56) Ｔ At least one test reception variable (54) characterizing the amount of light that can be captured using the Ｔ At least one receiving area (56) is divided into a test receiving area (56) for the purpose of generating a Ｔ ) and means for evaluating at least some of the received variables (54); At least one test receiving variable (54 Ｔ ) at least one measured receiving variable (54 Ｍ means for generating at least one fault condition when the amount of light characterized using the threshold is greater than the amount of light characterized using the threshold; An optical detection device (12), comprising:

9. At least one measurement receiving area (56 Ｍ ) and at least one test receiving area (56 Ｔ ) are formed from the same type of receiving area (56), and / or at least one measurement receiving area (56 Ｍ ) and / or at least one test receiving area (56 Ｔ ) at different time intervals (TE Ｍ , T.E. Ｔ ) can be separately configured to record received variables (54) 9. The optical detection device according to claim 8.

10. 10. The optical detection device according to claim 8 or 9, characterized in that at least one receiver (52) has a plurality of point sensors, at least one line sensor and / or at least one area sensor used to generate a respective reception area (56).

11. A vehicle (10) having at least one optical detection device (12) for monitoring at least one monitoring area (14), said at least one optical detection device (12) comprising: at least one light emitting element (40) for transmitting an optical signal (42); at least two receiving areas (56) for receiving the reflected optical signal (42); at least one means (52) for determining a received variable (54) from the received optical signal (42); at least one means (38) for controlling said optical detection device (12) and for processing received variables (54); At least one means (62, 63) for checking the functional safety of said optical detection device (12); A vehicle (10) having said optical detection device (12) having at least one safety means (36, 47) for limiting the duration of said transmission of an optical signal (42) to a specified transmission time interval (TS) in order to achieve eye safety, and at least one inspection device (38, 62, 63) for said at least one safety means (36, 47), The inspection device (38, 62, 63), At least one measurement time interval (TE) is determined from at least one received optical signal (42). Ｍ At least one measurement receiving area (56) Ｍ At least one measured reception variable (54) characterizing the amount of light that can be captured using the Ｍ At least one receiving area (56) is measured to generate a receiving area (56). Ｍ ) and At least one test time interval (TE) is detected from at least one received optical signal (42). Ｔ At least one test receiving area (56) Ｔ At least one test reception variable (54) characterizing the amount of light that can be captured using the Ｔ At least one receiving area (56) is divided into a test receiving area (56) for the purpose of generating a Ｔ ) and means for evaluating at least some of the received variables (54); At least one test receiving variable (54 Ｔ ) at least one measured receiving variable (54 Ｍ means for generating at least one fault condition when the amount of light characterized using the threshold is greater than the amount of light characterized using the threshold. A vehicle (10) comprising:

12. 12. Vehicle according to claim 11, characterized in that the vehicle (10) comprises at least one driver assistance system (20).

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