JP2008058173A - Scanner for use in on-board radar device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a scanner for use in on-board radar device, capable of checking an abnormality in a scanning lens before the application of a laser beam from the device and stopping the system, if an abnormality is recognized, and improved in effect on the deterioration of emission-luminance, the service life, the consumption current and the like. <P>SOLUTION: A light beam caused by current is emitted from LD28. The direction of the light beam is changed by a scanning lens 40. The position of the scanning lens 40 is detected by PSDs 25a and 25b. The scanning lens 40 is moved by an actuator member 21. An abnormality of the actuator member 21 is detected by CPU 20, at least based on information on the position of the scanning lens 40 moved by the actuator member 21 and detected by PSD 25a and PSD 25b. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a laser scanner device that scans a light beam to detect an obstacle, and more particularly, to a laser scanner device that has a self-diagnosis function in a scanning lens that scans light within a predetermined range.

  In recent years, a system that detects the preceding vehicle and obstacles in the vehicle, informs the driver of the information, and automatically controls the speed of the own vehicle so that the distance between the preceding vehicle and the preceding vehicle is maintained at a predetermined distance. Has been proposed and put into practical use as a device for assisting driving.

  This system uses an in-vehicle distance measuring device that measures the position and distance of a preceding vehicle or an obstacle, and as one of them, a light beam such as a laser beam is applied to a predetermined area around the vehicle. A laser radar device is known that measures the position of an object, its distance, and the like by emitting light while scanning the region and receiving reflected light from the object existing in the emission direction.

  This laser radar apparatus scans laser light with a scanner device provided in the apparatus. If the scanner device malfunctions and stops for some reason, the laser beam is continuously irradiated in the same direction. When the continuously irradiated laser light passes through a certain path and is irradiated to the outside of the laser radar apparatus, there is a possibility that the laser light exceeding the safety standard is irradiated to the human eye. For this reason, measures to prevent the human eye from being exposed to danger due to the abnormal stop of the scanner are indispensable for the laser radar apparatus.

  In view of that, a laser radar device having a self-diagnosis function for detecting an abnormality or abnormal stop of a scanner is proposed in Patent Document 1 below.

  According to the conventional example shown in FIG. 14 (FIG. 5 of Patent Document 1 below), the scanner device has a motor structure including a polygon mirror. Laser light is emitted from a laser diode (hereinafter referred to as LD) serving as a light source, reflected once by a mirror, then further reflected by a rotating polygon mirror, and emitted outside the laser radar apparatus. By rotating the polygon mirror, the laser beam is scanned from left to right according to an example. Furthermore, this polygon mirror has a different tilt angle with respect to the vertical direction for each surface. With this structure, it is possible to scan up to six stages in the vertical direction.

The self-diagnosis function in the conventional example described above is implemented by a self-diagnosis optical path prepared separately from the optical path used for scanning, using the above structure. The optical path for self-diagnosis is such that after the laser light is reflected by the polygon mirror and then by the reflecting member in the laser radar apparatus, it enters the light receiving photodiode (hereinafter referred to as PD). In order to irradiate the optical path for self-diagnosis with the laser beam, the laser beam is periodically irradiated at the same timing, and the abnormality of the scanner device is determined by whether or not the laser beam is received by the light receiving PD. If there is an abnormality in the scanner device, the light receiving PD cannot receive the light periodically or continues to receive the light, so that the abnormality of the scanner device can be determined.
JP 2002-31685 A

  However, the abnormality detection method described above does not directly detect the abnormality of the scanner device, but emits a laser beam from a light source, passes through a path for a self-diagnosis function, and receives light with a light receiving PD. Therefore, there is a possibility that the abnormality cannot be accurately detected due to factors other than those caused by the scanner device.

  For example, factors considered on the light source side are the life of the light source, a decrease in light emission luminance, fluctuations in the supply current to the light source, and the like. A possible factor on the light receiving side is an abnormal operation of the light receiving PD and the light receiving circuit. Possible factors in the path for the self-diagnosis function are foreign matters generated during assembly, or missing parts of internal parts generated due to secular change, etc., and if the laser light is blocked by this, Although there is no abnormality in the scanner device, the abnormality is diagnosed.

  In addition, even when the scanner device abnormally stops in the region where light is scanned outside the laser radar device, when a situation occurs in which light for abnormality diagnosis reaches the light receiving PD via some path due to a foreign object or the like, The scanner device is determined to be normal, and light emission continues. At this time, light exceeding the safety standard may be emitted in the same direction.

  From the above problem, it is desirable to directly detect abnormality of the scanner device. As a means for realizing this structure, in the proposed scanner device, when the laser beam is not emitted (for example, at the initial stage of turning on the power to the laser radar device or at the stand-by before the laser beam is emitted after moving the optical element) In addition, by directly measuring and self-diagnosing the position and behavior of the movable part including the optical element used for scanning, the presence or absence of an abnormality of the scanner is directly confirmed. If the above is recognized, the scanner is stopped, and a signal indicating abnormality is transmitted to the control unit of the laser radar device.

  That is, the invention described in claim 1 is a scanner for use in an on-vehicle radar device that scans a light beam over a predetermined range and receives reflected light of the scanning light to detect an obstacle, Based on a first light source for generating a light beam, an optical element for changing the direction of the light beam generated by the first light source, an optical element position detecting means for detecting the position of the optical element, and a signal indicating the position Optical element driving means for moving the optical element, and at least the position of the optical element moved by the optical element driving means based on the information detected by the optical element position detecting means. And an abnormality detection means for detecting the abnormality.

  According to a second aspect of the present invention, in the first aspect of the invention, the optical element driving means is capable of moving the optical element in a two-dimensional direction.

  According to a third aspect of the present invention, in the first aspect of the present invention, the position detection means includes a slit that moves together with the optical element, and a slit that is fixed to the light source with the slit interposed therebetween. It is characterized by comprising two light sources and an optical position detection element.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the abnormality detecting means detects an abnormality when the radar apparatus is activated and when the light source does not generate a light beam. The process which performs is performed.

  The invention according to claim 5 is the invention according to claim 4, wherein the abnormality detection means executes the abnormality detection process at a predetermined time interval during the standby.

  According to a sixth aspect of the invention, in the third aspect of the invention, the abnormality detecting means executes a process of detecting an abnormality when the current supplied to the second light source is changed. And

  According to a seventh aspect of the present invention, in the first aspect of the present invention, the abnormality detection means includes a current output from a power source that supplies a current to the radar device, the first light source, and a second When at least one of the current supplied to the light source, the current supplied to the optical element driving means, and the temperature of the environment in which the radar apparatus is installed exceeds a predetermined range, it is detected as an abnormality. And

  According to an eighth aspect of the present invention, there is provided a scanner for use in an on-vehicle radar device including a scanner that scans a laser beam over a predetermined range, in order to scan the laser light source and the laser light from the laser light source. A scanning optical element whose position can be moved, a sensor for detecting the position of the scanning optical element, and whether or not the scanning optical element is operating normally based on position information detected by the sensor And a diagnostic unit for self-diagnosis.

  According to a ninth aspect of the invention, in the invention according to the eighth aspect of the invention, the diagnostic unit includes the scanning optical element at least before the laser light emission is permitted and when the laser light is not emitted including standby. It is characterized by performing self-diagnosis of operation.

  According to a tenth aspect of the present invention, in the invention according to the ninth aspect, the diagnostic section performs a self-diagnosis of the operation of the scanning optical element at a predetermined interval during the standby. And

  According to an eleventh aspect of the present invention, in the invention according to the eighth aspect, the moving direction of the scanning optical element is a maximum moving position in four directions, up, down, left, and right.

  A twelfth aspect of the invention according to the eighth aspect of the invention further comprises a judging means for judging that the moving position of the scanning optical element has moved to a predetermined position. When the means determines that the moving position of the scanning optical element has moved to a predetermined position, the scanning optical element moves to a predetermined standby position and waits for the next instruction. Features.

  The invention according to claim 13 is the invention according to claim 12, wherein the sensor is constituted by a position detecting element, and the judging means judges from position information based on an output of the position detecting element. To do.

  The invention according to claim 14 is the invention according to claim 8, wherein the position of the scanning optical element is controlled by an actuator.

  According to the present invention, the abnormality of the scanning optical element can be confirmed before the laser beam is emitted from the apparatus, and when the abnormality is recognized, the system can be stopped, and the deterioration of the emission luminance, the lifetime, the consumption It is possible to provide a scanner for use in an on-vehicle radar device with improved influence on current and the like.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1A and 1B show a scanner used in an on-vehicle radar device according to an embodiment of the present invention. FIG. 1A is a block diagram showing an overall configuration, and FIG. 1B is a diagram of an actuator member of FIG. It is the perspective view which expanded and showed the part.

  First, the principle of laser radar applied to a scanner used in the on-vehicle radar device of the present invention will be described with reference to FIGS.

  The scanner has a scanner control computer (hereinafter referred to as CPU) 20 that performs control for emitting laser light and operating the laser light in an arbitrary direction. The CPU 20 includes an actuator member 21, which is an optical element driving unit for driving a scanning lens (optical element) 40, which will be described later, an actuator driver 22, and a driver circuit for driving light emitting diodes (LEDs) 23a and 23b. Current-voltage conversion circuit (IV circuit) for converting the position signals of the LED drive 24 and the position detection elements (PSDs) 25a and 25b, which are optical element position detection means, into current / voltage and inputting them to the A / D port of the CPU ) 26a and 26b, a thermistor circuit 33 for the temperature detection thermistor 32, and a laser radar control board 50 are connected.

  The actuator member 21 is for driving a scanning lens 40 described later, and is driven by an actuator driver 22 in accordance with a control signal from the CPU 20. The actuator member 21 is provided with the scanning lens 40 and the thermistor 32. In FIG. 1B, slits 45 a and 45 b for detecting the position of the actuator member 21 are formed in the vertical direction of the scanning lens 40. Furthermore, a plurality of coils 47 are arranged on both the front and back surfaces of the actuator member 21. The thermistor 32 monitors the temperature in the apparatus for adjusting the current flowing through the LEDs 23a and 23b in order to make the amount of light emitted to the PSDs 25a and 25b uniform.

  The LEDs 23a and 23b are driven by the LED drive 24 to emit light, and this light emission gives position information to the PSDs 25a and 25b through the slits 45a and 45b formed in the actuator member 21, respectively. The PSDs 25a and 25b detect the movement of the actuator member 21 to a predetermined position by the LEDs 23a and 23b and the slits 45a and 45b. The position signals output from these PSDs 25a and 25b are converted from current to voltage by the current / voltage conversion circuits 26a and 26b and input to the A / D port of the CPU 20.

  The laser diode (LD) 28 as the first light source emits light by driving the light emitting circuit 29 in accordance with a laser emission command from the laser radar control board 50. The laser light emitted from the LD 28 is irradiated to the object 41 through the lenses 38 and 39 and the scanning lens 40 provided in the laser frame. Then, the light reflected and returned by the object 41 is condensed by the condenser lens 42 and received by the light receiving photodiode (PD) 35. The light received by the PD 35 is converted into an electrical signal here and then supplied to the laser radar control board 50 via the light receiving circuit 36.

  In such a configuration, initial setting is performed in accordance with power-on of the apparatus (not shown), and after the optical axis correction value and temperature data are set, the laser beam is emitted from the LD 28. The irradiated laser beam is shaped in a beam shape while passing through the lenses 38 and 39 and the scanning lens 40 of the lens frame, and is arbitrarily set up and down, left and right by the scanning lens 40 fitted in the actuator member 21. Output to scan in direction.

  The LD 28 is driven by the light emitting circuit 29 according to a light emission command from the laser radar control board 50 to emit laser light. Then, the light reflected and returned by a certain object, for example, the object 41 is received by the PD 35 in the apparatus via the condenser lens 42. The light received by the PD 35 is level-converted by the light receiving circuit 36 and then sent to the laser radar control board 50.

  Thus, the time from laser light emission to light reception is calculated in the laser radar control board 50, thereby converting the distance from the apparatus to the object 41.

  Note that the scanning range by the LD 28 is the range shown in FIG. 4, and the vertical and horizontal directions can be sequentially scanned based on position information stored in a memory 78 described later.

  FIG. 2 is a cross-sectional view showing the structure of the scanner portion of the scanner.

  In FIG. 2, the scanner unit includes a base frame 61 and an outer frame 62 that covers the entire scanner unit together with the base frame 61. An LD 28 is fitted on the base frame 61, and lenses 38 and 39 provided on the lens frames 64 and 65 and a scanning lens 40 fitted on the actuator member 21 are arranged on the optical axis thereof. ing. In the peripheral portion of the actuator member 21, the fixing members 68 and 70 are disposed with a predetermined gap between the actuator member 21 and the front and back surfaces of the actuator member 21.

  As described above, the plurality of coils 47 are arranged on the front and back surfaces of the actuator member 21. In FIG. 2, the fixing member 68 side is shown as a coil 47a, and the fixing member 70 side is shown as a coil 47b. A plurality of magnets 67 are mounted on the surface of the fixing member 68 facing the coil 47a. Similarly, a plurality of magnets 69 are mounted on the surface of the fixing member 70 facing the coil 47b.

  The scanning lens 40 is operated up and down and left and right by a coil 47a and a magnet 67, and a coil 47b and a magnet 69. As a result, the emitted laser light moves in a scanning range described later.

  The laser beam emitted from the LD 28 is shaped into a beam shape while passing through the two lenses 38 and 39 and the scanning lens 40. The scanning lens 40 is scanned in the vertical and horizontal directions by moving the actuator member 21 in the direction perpendicular to the optical axis by the coil 47a and the magnet 67 and the coil 47b and the magnet 69 of the actuator member 21. The current flowing through the coils 47a and 47b is controlled by PWM control from the CPU 20, and the operation is controlled in an arbitrary direction by the magnets 67 and 69.

  For detection of predetermined coordinates of the actuator member 21, two orthogonal slits 45a and 45b formed in the actuator member 21 are used as shown in FIG. Light projected from the light emitting diodes 23a and 23b onto the slits 45a and 45b is received by the PSDs 25a and 25b. The received light is converted into photocurrent by PSDs 25a and 25b, and further current-voltage converted by current-voltage conversion circuits 26a and 26b. Thereafter, the CPU 20 performs A / D conversion, and the actuator member 21 is driven to an arbitrary position based on the A / D converted position information.

  By the way, since the light emission luminance of the LED for position detection changes depending on the temperature, there is a difference in the PSD gain at high and low temperatures. Therefore, correct position control becomes impossible. Regarding this point, in Japanese Patent Application No. 2006-158880, which is an earlier application by the present applicant, the light emission luminance is changed by controlling the current value flowing through the LED according to the temperature change, and a constant light reception luminance is obtained for the PSD. However, in the present invention, the thermistor 32 detects the environment in the apparatus, and the current value of the LED can be controlled together with the temperature change.

  FIG. 3 is a block diagram showing a configuration including a power supply system of the scanner. In FIG. 3, the LEDs 23a and 23b, the PSDs 25a and 25b, and the current-voltage conversion circuits 26a and 26b shown in FIG. 1 are shown as the LED 23, the PSD 25, and the current-voltage conversion circuit 26, respectively.

  In FIG. 3, a voltage of 12V, which is a main power source of a vehicle (not shown), is supplied to the ACT power source 75 and the other power source 76 for the actuator. The ACT power source 75 supplies a voltage of 7.0 V to the actuator driver 22 for driving the actuator member 21. The other power supply 76 supplies voltages of 5.0V, 3.3V, and 1.8V to each unit. The CPU 20 controls on / off of the ACT power source 75 and detects an overcurrent of both the power sources 75 and 76.

  The laser radar control board 50 is connected to a memory 78 that stores position information such as the scanner origin.

  The signal T_ARM from the actuator driver 22 is output to the CPU 20 at a high level (“H” level) when the temperature reaches the limit temperature due to the temperature rise of the actuator driver 22. With this output “H” signal, the CPU 20 notifies the laser radar control board 50 of the abnormality, thereby executing diagnosis and ensuring safety such as turning off the laser and turning off the system power.

  The temperature information from the thermistor 32 installed on the surface of the actuator member 21 monitors the temperature rise of the environment. Analog temperature information from the thermistor 32 is input to the A / D port of the CPU 20 where it is converted into a digital value.

  For the overcurrent detection connected to the power supply 75 and the other power supply 76, the CPU 20, the CPU core voltage, the reference voltage for current-voltage conversion, etc. are generated, but the overcurrent of these power supplies is detected, When an overcurrent is detected, a high level signal is output to the CPU 20, and when the “H” signal is sent to the CPU 20, the laser radar control board 50 is notified of abnormality detection and the light emission of the LD 28 is stopped and simultaneously the ACT 21 is stopped. It is something to be made.

  FIG. 4 is a diagram showing the projection coordinates of the screen when laser light is projected. In the figure, the scanning range scanned by one scan with respect to the maximum scanning range 51 that can be scanned by the scanner apparatus is defined as 52. The system origin 53 is provided at a position away from the reference point (lower left in FIG. 2) of the maximum scanning range 51 by a predetermined optical axis adjustment value. The system origin 53 is the origin when the scanner starts scanning. Become. The scanner origin 54 is the laser beam emission direction at the scanning lens stop position when the scanner is stationary and the power supply to the drive coil portion of the actuator member 21 is 0 mA. , Coordinates (20, 2). From here, the scanning lens is scanned at an arbitrary azimuth designation position (for example, 55). The scanner origin 54 is the center of the maximum scanning range 51 and the scanning range 52. Further, the position of the scanner origin 54 is the position with the least energy consumption in the azimuth direction.

  The projected coordinates are set to 0 to 40 in the azimuth direction from the left end of the screen and 0, 1, 2, 3, and 4 from the bottom to the elevation direction. In this scanner, the coordinates of the azimuth direction 0 to 40 are scanned at the level of the elevation coordinate 0, then the coordinates of the azimuth direction 0 to 40 are scanned at the level of the elevation direction 1, and then the elevation direction is similarly set. The operation is to continuously scan up to four stages.

  Next, with reference to the flowchart of FIG. 5, a flow from power-on of the scanner to transition to the standby state in one embodiment of the present invention will be described.

  As for turning on the power, as shown in the timing chart of FIG. 6, 12V as the main power (main) is energized in conjunction with an engine key of the vehicle not shown. Next, for example, after 5 ms, analog 5 V, and further after 10 ms, the logic system 5 V of the CPU 20 and the core power supply 1.8 V of the CPU 20 are sequentially turned on, and the CPU 20 is reset (for example, after 50 ms).

  When the CPU 20 is reset in this way, various initial processes such as setting the state of each port of the CPU 20 are performed in step S1. Next, in step S2, communication with the laser radar control board 50 is ensured to enable communication, and the self-diagnosis function is entered.

  In step S3, as a self-diagnosis function, a subroutine “overcurrent, temperature rise, actuator driver overcurrent detection” is executed, and an overcurrent abnormality of various power supplies (ACT power supply 75, other power supply 76) is diagnosed.

  FIG. 7 is a flowchart for explaining the processing operation of the subroutine “overcurrent, temperature rise, actuator driver overcurrent detection” in step S3 in the flowchart of FIG. In this subroutine, N = 5 indicates that the same operation is repeated five times. Further, details of overcurrent detection are well known, and therefore description thereof is omitted here.

  When this subroutine is entered, in step S21, it is determined whether or not the overcurrent of the other power source 76 generating the logic system of the CPU 20, the core power source, etc. is normal. Here, the current of each power supply is monitored, and if it does not exceed a certain constant current value among the repeated determinations five times, the process proceeds to step S22. On the other hand, if the current value exceeds a certain current value even once, the process proceeds to step S25, and the NG flag is set (← 1) assuming that the self-diagnosis is NG.

  In step S22, it is determined whether or not the current of the actuator driver 22 is normal. The actuator ACT power supply 75 monitors the actuator load current. If it is determined by this monitoring that the current value has not exceeded a certain current value among the five times, the process proceeds to step S23. On the other hand, if the current value exceeds a certain current value even once, the process proceeds to step S25 and the self-diagnosis is judged as NG.

  Further, in step S23, the thermistor 32 determines whether or not the environment in the apparatus has reached a certain temperature (for example, 85 ° C.). If the temperature does not exceed a certain temperature among the five times, the process proceeds to step S24, and the NG flag is reset (← 0) because the self-diagnosis is OK. On the other hand, if the temperature exceeds a certain temperature even once, the process proceeds to step S25 and the self-diagnosis is determined as NG.

  After the processing operation in step S24 or S25, the process proceeds to step S4 in the flowchart of FIG.

  In step S4, it is determined whether or not the self-diagnosis is OK. That is, in the subroutine “overcurrent, temperature rise, actuator driver overcurrent detection” in step S3, if there is no problem as a result of the determination five times, the process proceeds to step S5. However, in any determination, if it is NG even once, it is determined as NG by self-diagnosis, and the process proceeds to the subroutine “NG processing” in step S17.

  In step S5, it is determined whether or not the current position of the scanning lens 40 is at the scanner origin 54 (coordinates (20, 2)) shown in FIG. This is confirmed and determined based on whether or not it has moved to the designated coordinates based on the position information obtained from the PSDs 25a and 25b. If it is determined that the scanner unit is not located at the scanner origin 54, the process proceeds to step S6, and the movement to the scanner origin 54 is performed. If the scanning lens 40 is present at the scanner origin 54 in step S5, the process proceeds to step S7, and the processing operation of the subroutine “Verify vertical / horizontal position movement” is executed.

  FIG. 8 is a flowchart for explaining the processing operation of the subroutine “Verify movement of vertical and horizontal positions” in step S7 in the flowchart of FIG.

  When this subroutine is entered, first, in step S31, it is determined whether the vertical and horizontal orientations of the scanning lens 40 of the scanner unit have moved to the coordinates (20, 4). Here, the movement of the coordinates is confirmed five times, but if it is determined that the coordinates are not even once, the process proceeds to step S36, and if it is determined that all the coordinates are moved, the process proceeds to step S32.

  In step S32, it is determined whether the vertical and horizontal directions of the scanning lens 40 have moved to the coordinates (40, 2). Here, if it is determined that the coordinates are not, the process proceeds to step S36. If it is determined that all the coordinates are moved, the process proceeds to step S33. Similarly, in step S33, it is determined whether the vertical and horizontal orientations of the scanning lens 40 have moved to the coordinates (20, 0). Here, if it is determined that the coordinates are not, the process proceeds to step S36. If it is determined that all the coordinates are moved, the process proceeds to step S34.

  In step S34, it is determined whether the vertical and horizontal orientations of the scanning lens 40 have moved to the coordinates (0, 2). Here, if it is determined that the coordinates are not, the process proceeds to step S36. If it is determined that all the coordinates are moved, the process proceeds to step S35.

  In step S35, the coordinates of all the positions in steps S31 to S34 can be confirmed, and the NG flag is reset (← 0) assuming that the self-diagnosis is OK. On the other hand, in step S36, the NG flag is set (← 1) because the self-diagnosis is NG. Thereafter, the subroutine is exited, and the process proceeds to step S8 in the flowchart of FIG.

  In step S8, it is determined whether or not the result of the position confirmation of the scanning lens 40 executed in step S7 is OK. If there is no problem in the position confirmation result, the process proceeds to step S9. If there is any problem in position movement even once, the process proceeds to the subroutine “NG process” in step S17.

  In step S9, it is determined again whether or not the current position of the scanning lens 40 is at the scanner origin 54 (coordinates (20, 2)) shown in FIG. Here, when it is determined that the scanning lens 40 is not at the scanner origin 54, the process proceeds to step S10 and the movement to the scanner origin 54 is performed. If the scanning lens 40 is present at the scanner origin 54 in step S9, the process proceeds to step S11, the system is turned on, and the distance measuring sequence is on standby.

  In subsequent step S12, position correction of the scanning lens 40 and various correction data based on temperature data of the thermistor 32 are set. Further, in step S13, a subroutine "system origin movement" process is executed. Here, the above-described corrected scanning lens 40 of each product is moved to the system origin (0, 0).

  Here, although it is a criterion for detecting abnormality of the actuator member 21 on which the scanning lens 40 is mounted, as shown in FIG. 4, when viewed at the position of the first self-diagnosis position coordinate (0, 2), the vertical direction If the center position is “2” coordinates, the left and right directions are “0” coordinates, and the movement angle from the center is 15 °, for example, the vertical direction is 0 ° ± 0.5 ° and the left / right direction is 15 ° ± 0.5 °. The fact that it is within the range is converted by the movement distance detected by the position detection function of the PSDs 25a and 25b, and an abnormality is judged. The detection of abnormality of the actuator member 21 is similarly determined for the other three directions.

  FIG. 9 is a flowchart for explaining the processing operation of the subroutine “system origin movement” in step S13 in the flowchart of FIG.

  When this subroutine is entered, it is first determined in step S41 whether or not the position of the scanning lens 40 has moved to the system origin 53. Here, if the scanning lens 40 has moved to the position of the system origin 53, the process proceeds to step S42 described later. On the other hand, when it has not moved to the system origin 53, it transfers to step S43.

  In step S43, the set current of the LEDs 23a and 23b is increased. This is because the amount of light incident on the LEDs 23a and 23b projecting light on the PSDs 25a and 25b for position confirmation is increased in order to increase the S / N of the PSDs 25a and 25b and increase the accuracy of position verification. Is increasing.

  Next, in step S44, the position data of the PSDs 25a and 25b are read and the positions of the PSDs 25a and 25b are verified. In step S 45, the position of the scanning lens 40 is moved to the system origin 53. In a succeeding step S46, it is determined whether or not the moved position is the system origin 53. If the scanning lens 40 has been moved to the system origin 53, the process proceeds to step S47. If not, the process proceeds to step S48. When the process proceeds to step S48, self-diagnosis is performed for insufficient brightness of the LEDs 23a and 23b and insufficient sensitivity of the PSDs 25a and 25b.

  In step S47, when the current LED setting current is set, the current setting is set to the environmental temperature measurement value. Thereafter, in step S42, the NG flag is reset (← 0) because the self-diagnosis is OK. On the other hand, in step S48, the NG flag is set (← 1) because the self-diagnosis is NG. Thereafter, the subroutine is exited and the process proceeds to step S14 in the flowchart of FIG.

  In step S14, it is determined whether or not the movement of the scanning lens 40 to the system origin 53 is OK. As a result, when the scanning lens 40 is correctly moved to the system origin 53, the process proceeds to step S15 and the system enters a standby state. Here, the laser radar control board 50 is on standby until a distance measurement instruction is issued. When the standby state is entered, an intermittent operation for confirming movement in four directions at intervals of 1 minute, for example, is performed in order to confirm the abnormality of the scanning lens 40 described above.

  In step S16, power is supplied to the laser by the distance measurement operation by the operator and the distance measurement operation is started in the direction control sequence.

  Further, in the subroutine “NG process” in step S17, the NG process is executed when an abnormality is confirmed in the subroutines in steps S3, S7, and S13 described above.

  FIG. 10 is a flowchart for explaining the processing operation of the subroutine “NG processing” in step S17 in the flowchart of FIG.

  When this subroutine is entered, error message data is transferred to the laser radar control board 50 in step S51. The laser radar control board 50 transmits an abnormality to a vehicle-side system CPU (not shown), and turns off the power of the scanner in step S53. Based on information from the laser radar control board 50, the system CPU performs processing such as warning to the vehicle driver and cancellation of the vehicle speed control operation.

  By the way, as described above, in Japanese Patent Application No. 2006-158880, which is an earlier application by the present applicant, the current flowing through the LED is controlled by a temperature change to change the light emission luminance, and the PSD has a certain threshold value. Although the light receiving luminance can be obtained, the atmosphere in the scanner is detected, and the current value of the LED can be controlled together with the temperature change. The intermittent operation described above can also be performed at a timing synchronized with the change in the current value of the LED.

  FIG. 11 is a table showing an example of changes in the current value of the LED.

  Here, the temperature represents the ambient atmosphere temperature, and the rated value of the LED forward current with respect to the temperature change from −35 ° C. to + 90 ° C. and the current actually passed through the LED are shown. For example, in the case of a low temperature of 25 ° C., the current value flowing through the LED is 22 mA, and when the temperature rises to 30 ° C., the current value flowing through the LED is 24 mA. In this case, the current value of the LED can be changed in five steps of extremely low temperature, low temperature, normal temperature, high temperature, and extremely high temperature.

  FIG. 12 is a flowchart for explaining the processing operation when there is a change in the LED forward current value.

  When this routine is started, temperature information is acquired in step S61. Then, in the subsequent step S62, it is determined whether or not the temperature acquired in step S61 has exceeded a switching temperature as shown in the table of FIG. If the switching temperature is exceeded, the process proceeds to step S 63, and the temperature information is transmitted from the laser radar control board 50 to the CPU 20. Next, in step S64, the table of FIG. 11 is referred to. In step S65, an appropriate LED current value is set according to the data in the referenced table.

  After the current value is set in this way, a subroutine for confirming the movement of the vertical and horizontal positions in step S66 (step S7 in the flowchart of FIG. 5) is executed to perform self-diagnosis of the scanning lens.

  On the other hand, if the switching temperature is not exceeded in step S62, the process proceeds to steps S67 and S68, and in the same manner as steps S15 and S16 in the flowchart of FIG. to go into.

  When the ambient temperature rises and falls as described above, and the LED setting current is variable, the scanning lens 40 is scanned, and during the distance measuring operation, the scanning lens 40 is scanned to perform self-diagnosis. Can not do. Accordingly, during the scanning of the scanning lens 40, the self-diagnosis of the scanning lens 40 is not performed, and the self-diagnosis by scanning of the scanning lens 40 is performed at the following timing.

  That is, in step S65 in the flowchart of FIG. 12, it is stored that the CPU has changed the current after the LED current value setting has been changed (the LED setting current variable flag is set). When this flag is on, for example, when the distance between this device and the preceding vehicle or object is 100 m or longer and this state continues for 1 second or longer, the distance measuring sequence is stopped and the scanning lens self-diagnosis is performed. Is done.

  The self-diagnosis in this case will be described with reference to the flowchart of FIG.

  When this sequence is started, the LED setting value change flag is set to “1” in step S71. Next, in step S72, the distance measurement result is compared with a state in which the distance measurement result described above has a time of 100 m or longer for 1 second or longer. Here, when the state is recognized, the process proceeds to step S73 (step S7 in the flowchart of FIG. 5), and self-diagnosis of the scanning lens 40 is performed. When the self-diagnosis is completed, the LED setting value change flag is set to “0” (cleared).

  Therefore, the timing of comprehensive self-diagnosis is when the initial setting when the system power is turned on, self-diagnosis by intermittent operation during standby, and when the LED current value is changed.

  In the scanner used in the on-vehicle radar device according to the present invention, the scanning lens that scans the laser beam when the laser beam is not emitted, such as before the laser beam is emitted at the time of initial power-on to the system or during standby, to a predetermined range is a laser. By making a self-diagnosis before the light is emitted, an abnormality of the scanning lens is confirmed, and when an abnormality is recognized, the system is stopped.

  In addition, the scanner used in the on-vehicle radar device of the present invention is a system that shifts to an operating state in response to a driver's command, but has a function of performing a similar self-diagnosis at a certain period of time during non-operation. In the same manner, when the abnormality occurs, the laser beam is not emitted and the system is stopped before the emission.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention.

  Further, the above-described embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, even if some constituent requirements are deleted from all the constituent requirements shown in the embodiment, the problem described in the column of the problem to be solved by the invention can be solved, and the effect described in the column of the effect of the invention Can be extracted as an invention.

BRIEF DESCRIPTION OF THE DRAWINGS The scanner used for the vehicle-mounted radar apparatus in one Embodiment of this invention is shown, (a) is a block diagram which showed the whole structure, (b) expanded the part of the actuator member of (a). It is the perspective view shown. It is sectional drawing which shows the structure of the scanner part of the scanner in this embodiment. 1 is a block diagram showing a configuration including a power supply system of a scanner in an embodiment of the present invention. FIG. It is a figure showing the projection coordinates of the screen at the time of projecting a laser beam. It is a flowchart explaining the flow from power-on of the laser scanner apparatus in one Embodiment of this invention until it transfers to a standby state. 6 is a timing chart for explaining an operation at the time of power-on of the scanner in one embodiment of the present invention. 6 is a flowchart for explaining a processing operation of a subroutine “overcurrent, temperature rise, actuator driver overcurrent detection” in step S3 in the flowchart of FIG. 5. FIG. 6 is a flowchart for explaining a processing operation of a subroutine “Verify movement of vertical and horizontal positions” in step S7 in the flowchart of FIG. 5; 6 is a flowchart for explaining a processing operation of a subroutine “system origin movement” in step S13 in the flowchart of FIG. 5. FIG. 6 is a flowchart for explaining a processing operation of a subroutine “NG processing” in step S <b> 17 in the flowchart of FIG. 5. It is the table | surface which showed the example of a change of the electric current value of LED. It is a flowchart for demonstrating the processing operation | movement when there exists a change of LED forward current value. It is a flowchart explaining the example of the other processing operation which performs the self-diagnosis of a scanning lens. The structural example of the conventional reflection measuring apparatus is shown, (a) and (b) are the figures which showed the state of the different rotation position of a polygon mirror from upper direction, (c) is a sectional side view. It is the figure which showed the example of the conventional reflection measuring apparatus, and showed the relationship between a laser radar apparatus and a target object.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 20 ... Scanner control computer (CPU), 21 ... Actuator member, 22 ... Actuator driver, 23a, 23b ... Light emitting diode (LED), 24 ... Light emitting diode drive, 25a, 25b ... Position detection element (PSD), 26a, 26b ... Current-voltage conversion circuit (IV circuit) 28 ... Laser diode (LD) 29 ... Light emitting circuit 32 ... Thermistor 35 ... Photo diode (PD) 40 ... Scanning lens 41 ... Object 45a, 45b ... Slit, 47, 47a, 47b ... Coil, 50 ... Laser radar control board, 67, 69 ... Magnet, 68, 70 ... Fixed member, 75 ... ACT power source, 76 ... Other power source, 78 ... Memory.

Claims (14)

A scanner used in an on-vehicle radar device that scans a light beam over a predetermined range, receives reflected light of the scanning light, and detects an obstacle,
A first light source that generates the light beam by an electric current;
An optical element for changing the direction of the light beam generated by the first light source;
Optical element position detecting means for detecting the position of the optical element;
Optical element driving means for moving the optical element based on a signal indicating a position;
An abnormality detecting means for detecting an abnormality of the optical element driving means based on information detected by the optical element position detecting means, at least the position of the optical element moved by the optical element driving means;
A scanner for use in a vehicle-mounted radar device.   2. The scanner used in an on-vehicle radar device according to claim 1, wherein the optical element driving means is capable of moving the optical element in a two-dimensional direction.   The position detection means includes a slit that moves together with the optical element, a second light source that is fixed to the light source with the slit interposed therebetween, and an optical position detection element. Item 14. A scanner used in the on-vehicle radar device according to Item 1.   The in-vehicle radar according to any one of claims 1 to 3, wherein the abnormality detection means executes a process of detecting an abnormality at the time of startup of the radar apparatus and at a standby time when the light source does not generate a light beam. Scanner used in the device.   5. The scanner for use in an on-vehicle radar device according to claim 4, wherein the abnormality detection means executes the abnormality detection process at predetermined time intervals during the standby.   4. The scanner used in the on-vehicle radar device according to claim 3, wherein the abnormality detection means executes processing for detecting an abnormality when a current supplied to the second light source is changed. The abnormality detection means is
The current output from the power supply that supplies current to the radar device, the current supplied to the first light source and the second light source, the current supplied to the optical element driving means, and the environment in which the radar device is installed 2. The scanner for use in an in-vehicle radar device according to claim 1, wherein an abnormality is detected when at least one of the temperatures exceeds a predetermined range. A scanner used in an on-vehicle radar device including a scanner that scans a laser beam over a predetermined range,
A laser light source;
A scanning optical element whose position can be moved to scan the laser beam from the laser light source;
A sensor for detecting a position of the scanning optical element;
Based on the position information detected by the sensor, a diagnostic unit for self-diagnosis as to whether or not the scanning optical element is operating normally;
A scanner for use in a vehicle-mounted radar device.   9. The vehicle-mounted device according to claim 8, wherein the diagnostic unit performs self-diagnosis of the operation of the scanning optical element at least before permission to emit the laser light and when the laser light is not emitted including standby. Scanner used in radar equipment.   10. The scanner used in the on-vehicle radar device according to claim 9, wherein the diagnostic unit performs self-diagnosis of the operation of the scanning optical element at a predetermined interval during the standby.   9. The scanner used in the on-vehicle radar device according to claim 8, wherein the moving direction of the scanning optical element is a maximum moving position in four directions, up, down, left and right. A judgment means for judging that the moving position of the scanning optical element has moved to a predetermined position;
When it is determined by the determination means that the moving position of the scanning optical element has moved to a predetermined position, the scanning optical element moves to a predetermined standby position and waits until the next instruction is received. The scanner used for the vehicle-mounted radar apparatus according to claim 8.   13. The scanner for use in an on-vehicle radar device according to claim 12, wherein the sensor is constituted by a position detection element, and the determination means determines from position information based on an output of the position detection element.   9. The scanner used in the on-vehicle radar device according to claim 8, wherein the position of the scanning optical element is controlled by an actuator.

Images