Scanner device, in particular for a lidar sensor

Abstract

A scanner device, in particular for a lidar sensor (2), is proposed, comprising at least one deflection unit (3) for deflecting radiation, in particular laser radiation, wherein the deflection unit (3) is movably mounted about a rotational axis (4) of the deflection unit (3), and at least one drive unit (5) which is provided for driving the deflection unit (3) to a tilting movement about the rotational axis (4) of the deflection unit (3), wherein the drive unit (5) comprises at least one motor (6) and at least one crank element (7), wherein the motor (6) is provided for rotating the crank element (7) about a rotational axis (8) of the crank element (7), wherein the drive unit (5) comprises at least one connecting element (9) which is rotatably mounted on the crank element (7) at a first bearing point (10) and transversely, in particular perpendicularly, offset to the rotational axis (8) of the crank element (7).and which is mounted on the deflection unit (3) at a second bearing point (11) spaced apart from the first bearing point (10) in a rotationally movable manner and transversely, in particular perpendicularly, offset to the axis of rotation (4) of the deflection unit (3), wherein the motor (6) is provided to dynamically adjust a rotor angular frequency during at least one revolution such that a tilting angular velocity of the deflection unit (3) is at least substantially constant over at least a tilting angular sub-range (28).

Description

[0001] The invention relates to a scanner device, in particular for a lidar sensor. Furthermore, the invention also relates to a computing device and a scanner system. Furthermore, the invention relates to a corresponding lidar sensor and a vehicle. Furthermore, the invention also relates to a method for controlling a corresponding scanner device.

[0002] Modern vehicles (cars, vans, trucks, motorcycles, etc.) are equipped with a multitude of sensors that provide information to the driver and control individual vehicle functions partially or fully automatically. Sensors record the vehicle's surroundings and other road users. Based on the recorded data, a model of the vehicle's environment can be created, and changes in this environment can be responded to.

[0003] An important sensor principle for environmental detection is LIDAR (light detection and ranging) technology. A LIDAR sensor is based on the emission of light signals and the detection of the reflected light. In the future, LIDAR sensors will become an essential component for autonomous vehicles. Scanning LIDAR sensors comprise a scanning mechanism that uses radiation, particularly a laser beam, to scan a field of view to be monitored. Examples of known scanning mechanisms from the state of the art include polygon scanners and galvanometer-driven mirrors. In the prior art, the same scanner is preferably used for both emitting and receiving light. While a transmitted beam often has a small beam diameter of a few millimeters, a large aperture on the order of several square centimeters is preferred on the receiving side.Polygon scanners require a large installation space and extensive optical coating. Furthermore, meaningful measurements are not possible while the laser beam is aligned with a facet break. Due to the large mass of the polygon mirror, it is not possible to vary the speed during one rotation of the rotating polygon mirror. Furthermore, a high duty cycle with a large beam diameter or large optical reception aperture can only be achieved with a very large diameter polygon mirror, which is not feasible due to limited installation space. Galvanometer-driven mirrors also require a large installation space and can only scan small fields of view. Galvanometers can generally achieve approximately linear or sinusoidal temporal profiles of the deflection angle, which are not optimal in terms of field-of-view scanning behavior.Due to the high angular velocities during beam deflection, the scanning mechanisms known from the state of the art can only achieve a small detection range or a low horizontal resolution.

[0004] A scanner device, in particular for a lidar sensor, is proposed. The scanner device comprises at least one deflection unit for deflecting radiation, in particular laser radiation. The deflection unit is mounted so as to be movable about a rotational axis of the deflection unit. The scanner device comprises at least one drive unit, which is provided for driving the deflection unit to perform a tilting movement about the rotational axis of the deflection unit. The drive unit has at least one motor. The drive unit has at least one crank element. The motor is provided for rotating the crank element about a rotational axis of the crank element. The drive unit has at least one connecting element, which is mounted on the crank element at a first bearing point so as to be rotatably movable and offset transversely, in particular perpendicularly, to the rotational axis of the crank element.The connecting element is mounted on the deflection unit at a second bearing point spaced apart from the first bearing point, and is mounted on the deflection unit in a manner that is transversely, in particular perpendicularly, offset from the rotational axis of the deflection unit. The motor is designed to dynamically adjust a rotor angular frequency during at least one revolution such that a tilt angle speed of the deflection unit is at least substantially constant over at least one tilt angle subrange.

[0005] The scanner device is preferably intended for use in a lidar sensor. The lidar sensor is preferably intended for use in a vehicle. In particular, the lidar sensor can be intended to detect objects in the vehicle's surroundings, for example, to enable at least partially autonomous driving functions of the vehicle. "Intended" should be understood in particular to mean specially programmed, specially equipped, and / or specially designed. The fact that an object is intended for a function should be understood in particular to mean that the object performs the function in at least one operating state.

[0006] The lidar sensor preferably comprises at least one radiation source designed to emit radiation, in particular laser radiation. The scanner device is designed, in particular, to scan the laser radiation across a field of view of the lidar sensor. In particular, the scanner device can be designed to direct radiation reflected back to the lidar sensor in an environment surrounding the lidar sensor to a receiving unit of the lidar sensor, which is designed, in particular, to detect the reflected radiation. Alternatively, it is conceivable for the lidar sensor to have at least two scanner devices, wherein at least one scanner device is designed to direct radiation to be emitted and at least one further scanner device is designed to direct received radiation.The scanner device is preferably provided to deflect the radiation in a single plane, for example a horizontal or vertical field of view of the lidar sensor. In particular, the lidar sensor can have at least one further scanner device that is provided to cooperate with the scanner device in order to scan a three-dimensional field of view. The further scanner device can in particular be provided to deflect the radiation in a plane that extends perpendicular to the plane in which the scanner device deflects radiation. The further scanner device can in particular be designed analogously to or differently from the scanner device according to the invention. The further scanner device can preferably be designed as a solid-state scanner, in particular as a PiC (photonic integrated circuit).For example, the solid-state scanner can emit a vertical beam of radiation into the environment. In particular, the solid-state scanner can receive radiation reflected from the environment. Alternatively, separate transmitter and receiver units could be used.

[0007] The deflection unit preferably comprises at least one mirror surface that is reflective at least in a wavelength range in which the lidar sensor operates. In particular, the mirror surface is intended to reflect radiation incident on it. The deflection unit preferably comprises at least one mirror support on which the mirror surface is arranged. In particular, the mirror support is mounted so as to be rotatably movable about the rotation axis of the deflection unit, for example on a mirror holder and / or a support unit of the scanner device. The rotation axis of the deflection unit preferably extends parallel to the mirror surface. The rotation axis of the deflection unit and the mirror surface extend in particular perpendicular to the plane in which the scanner device, in particular the deflection unit, deflects the radiation.In particular, the deflection unit deflects radiation incident on the mirror surface from a specific direction in different directions depending on different angular positions, in particular tilt positions, of the deflection unit around the rotation axis of the deflection unit. A field of view scanned by the deflection unit depends in particular on the angular positions of the deflection unit at two reversal points of the deflection unit in different directions of rotation around the rotation axis of the deflection unit.

[0008] The motor is preferably designed as an electric motor, for example as a DC motor, in particular a brushless one, as a stepper motor or the like. The crank element can preferably be directly coupled to the motor, in particular in a rotationally fixed manner, for example, fixed to a drive shaft of the motor. The crank element can in particular be designed as a crank disk, as a crank arm, as a crank cuboid, or as another crank element that appears appropriate to a person skilled in the art. In particular, the drive shaft of the motor can run parallel, preferably coaxially, to the rotational axis of the crank element. Alternatively, it is conceivable for the drive unit to have at least one transmission unit, in particular a gear, via which the crank element is coupled to the motor. The motor is in particular intended to drive the crank element to rotate about the rotational axis of the crank element.In particular, the rotational axis of the crank element can run through a geometric center and / or a center of mass of the crank element and in particular perpendicular to a main extension plane of the crank element. Alternatively, it is conceivable for the rotational axis of the crank element to run eccentrically through the crank element and in particular perpendicular to the main extension plane of the crank element. A "main extension plane" of an object should be understood in particular as a plane that is parallel to a largest side surface of a smallest imaginary cuboid that just completely encloses the object and in particular runs through the center of the cuboid. The motor can in particular be arranged, in particular fixed, on the support unit.

[0009] The connecting element is preferably provided to mechanically couple the crank element and the deflection unit to one another, in particular in terms of force transmission. In particular, the crank element and the deflection unit are arranged at a distance from one another. The connecting element is preferably designed as a rod, in particular as a connecting rod. The first bearing point is preferably arranged in a first end region of the connecting element. The first bearing point is preferably arranged on the crank element at a radial distance from the axis of rotation of the crank element. In particular, the connecting element is fastened to the crank element at the first bearing point and can rotate relative to the crank element about a first axis of rotation of the connecting element extending through the first bearing point. The second bearing point is preferably arranged in a second end region of the connecting element facing away from the first end region.The second bearing point is preferably arranged radially spaced from the rotational axis of the deflection unit on the deflection unit, in particular on the mirror support. In particular, the connecting element is attached to the second bearing point on the deflection unit, in particular on the mirror support, and can rotate about a second rotational axis of the connecting element extending through the second bearing point relative to the deflection unit, in particular to the mirror support.

[0010] Due to the eccentric mounting of the connecting element on the crank element, the position of the connecting element relative to the rotational axis of the deflection unit changes, particularly upon rotation of the crank element, depending on an angular position of the crank element. Due to the rotationally movable mounting of the deflection unit about the rotational axis of the deflection unit and the eccentric mounting of the connecting element on the deflection unit, a tilting movement of the deflection unit about the rotational axis of the deflection unit results, particularly depending on a change in position of the connecting element relative to the rotational axis of the deflection unit. In particular, the deflection unit tilts from a first reversal point to a second reversal point and back again during one revolution, in particular a 360° rotation, of the crank element.In particular, the design of the drive unit and the deflection unit allows a rotation of the crank element to be converted into a tilting of the deflection unit. Preferably, the size of the field of view scanned by the scanner device, in particular a maximum tilt of the deflection unit, can be adjusted by changing a diameter of the crank element, a length of the connecting element, a position of the first bearing point on the crank element, and a position of the second bearing point on the deflection unit, in particular on the mirror carrier.

[0011] Preferably, the motor is provided to rotate the crank element about the rotational axis of the crank element in order to generate an oscillatory tilting of the deflection unit about the rotational axis of the deflection unit. In particular, the deflection unit oscillates continuously between the two reversal points of the tilting movement as a function of a constant direction of rotation of the crank element during the rotation of the crank element. Depending on a constant angular velocity of the crank element, this results, for example, in a time-varying, periodic change in a tilt angle of the deflection unit and in particular in a deflection direction of the deflection unit. In particular, sinusoidal curves of the tilt angle and a tilt angular velocity result, in particular under a simplifying assumption of an infinitely long connecting element. The tilt angular velocity is in particular the time derivative of the tilt angle.

[0012] The rotational axes of the deflection unit, the crank element, and the connecting element preferably run parallel to one another. In particular, the rotational axis of the deflection unit, the rotational axis of the crank element, the first rotational axis of the connecting element, and the second rotational axis of the connecting element run parallel to one another. Alternatively, it is conceivable for the rotational axis of the crank element to run transversely, in particular perpendicularly, to the rotational axes of the deflection unit and the connecting element. In particular, the connecting element can be connected to the crank element and / or the deflection unit via at least one ball joint.

[0013] The motor is preferably designed as a servomotor. The servomotor is, in particular, an electric motor that allows control of the angular position of its drive shaft, its motor speed, and acceleration. In particular, the servomotor can have at least one sensor for position determination. In particular, at least the motor speed of the motor designed as a servomotor is adjustable.

[0014] The rotor angular frequency of the motor is in particular an angular frequency of a rotor of the motor. Preferably, the motor is designed as an electric motor comprising a static stator and a rotationally mounted rotor. The drive shaft of the motor is preferably connected to the rotor in a rotationally fixed manner. In particular, one revolution of the rotor corresponds to one revolution of the drive shaft and in particular to one revolution of the crank element. In particular, the rotation axis of the crank element corresponds to a rotation axis of the rotor. In particular, an angular frequency of the rotor corresponds to an angular frequency of the drive shaft and in particular to an angular frequency of the crank element. In particular, the angular velocity of an element, for example the rotor, is higher the higher the angular frequency of the element. In particular, the speed of the motor is higher the higher the angular frequency of the rotor.In particular, the speed of the motor is dynamically adjusted by dynamically adjusting the angular frequency of the rotor.

[0015] Preferably, the motor is designed to dynamically adjust the rotor angular frequency during each revolution of the rotor. In particular, the motor is designed to dynamically adjust the rotor angular frequency equally during each revolution of the rotor. Alternatively, it is conceivable for the motor to dynamically adjust the rotor angular frequency differently during successive revolutions of the rotor. Preferably, the motor is designed to change the rotor angular frequency several times during the revolution. In particular, the motor is designed to reduce the rotor angular frequency at least once during the revolution, preferably to reduce it at least once and increase it at least once, and particularly preferably to increase and reduce it several times.

[0016] The tilt angle sub-range is, in particular, a sub-range of a complete tilt angle range in which the deflection unit can be tilted between the two reversal points. For example, the complete tilt angle range can comprise 30° and the tilt angle sub-range 10°. For example, a tilt angle of the deflection unit at a center position of the deflection unit can be defined as 0°. The center position of the deflection unit is, in particular, a position of the deflection unit between the two reversal points of the deflection unit along the tilt path of the deflection unit with the same angular distance from the reversal points. The reversal points are, in particular, positions of maximum tilt of the deflection unit, at which the deflection unit changes one tilt direction into an opposite tilt direction. The tilt angles of the deflection unit at the reversal points can, for example, be defined as -15° and 15°.For example, the tilt angle subrange can extend from a tilt angle of -5° to a tilt angle of 5°. Preferably, the motor is designed to dynamically adjust the rotor angular frequency during rotation such that the tilt angle speed of the deflection unit is at least substantially constant over the tilt angle subrange, independent of the tilt direction of the deflection unit, in particular both during a tilting movement of the deflection unit from the first reversal point to the second reversal point and from the second reversal point to the first reversal point.Alternatively, it is conceivable that the motor is designed to dynamically adjust the rotor angular frequency during rotation such that the tilt angle speed of the deflection unit is at least substantially constant over the tilt angle sub-range depending on a tilt direction of the deflection unit, in particular during a tilting movement of the deflection unit from the first reversal point to the second reversal point or from the second reversal point to the first reversal point. In particular, the motor can be designed to dynamically adjust the rotor angular frequency during rotation such that the tilt angle speed of the deflection unit is at least substantially constant over several, in particular different, tilt angle sub-ranges.

[0017] Preferably, the motor is designed to dynamically adjust the rotor angular frequency during rotation such that the tilt angle speed of the deflection unit is at least virtually constant across the tilt angle sub-range. An at least substantially or virtually constant tilt angle speed across the tilt angle sub-range is understood to mean, in particular, that the tilt angle speed across the tilt angle sub-range has a maximum fluctuation of at most 5%, preferably of at most 2%, and particularly preferably of at most 1%. Preferably, the motor is designed to keep the rotor angular frequency at least substantially constant while the deflection unit moves across the tilt angle sub-range.

[0018] The tilt angle sub-range is in particular proportional to a partial field of view of the lidar sensor. The partial field of view is in particular a partial area, in particular a partial angle range, of the complete field of view of the lidar sensor. In particular, the scanner device scans the radiation while the deflection unit moves over the tilt angle sub-range at an at least substantially constant speed across the partial field of view. The partial field of view can in particular be a partial area of ​​the field of view of the lidar sensor of particular interest, known as a ROI (region of interest). For example, the partial field of view can contain a particularly large number of or important road users, for example pedestrians.

[0019] The inventive design of the scanner device advantageously enables a consistent detection quality of a lidar sensor in at least one partial field of view. Advantageously, a scanner device can be provided that enables particularly safe operation of the lidar sensor.

[0020] Furthermore, it is proposed that the motor is provided to dynamically adapt the rotor angular frequency during the at least one rotation such that the tilt angle speed of the deflection unit is lower over the at least one tilt angle sub-range than over further tilt angle sub-ranges. In particular, the motor is provided to dynamically adapt the rotor angular frequency during the rotation such that the tilt angle speed of the deflection unit is, on average, lower over the tilt angle sub-range than over further tilt angle sub-ranges. Preferably, the further tilt angle sub-ranges have a size comparable to the tilt angle sub-range, for example 10°. In particular, the further tilt angle sub-ranges have a size of at least 3°, preferably of at least 6°, and particularly preferably of at least 10°.Preferably, the motor is configured to dynamically adjust the rotor angular frequency during rotation such that the tilt angle speed of the deflection unit is lower across the tilt angle sub-range than as a function of a constant rotor angular frequency. Preferably, the motor is configured to set the rotor angular frequency lower while the deflection unit moves across the tilt angle sub-range than while the deflection unit moves across the other tilt angle sub-ranges. In particular, the lower the tilt angle speed in the tilt angle sub-range, the more radiation can be emitted into the corresponding partial field of view of the lidar sensor and / or received from the corresponding partial field of view of the lidar sensor.The more radiation emitted into and / or received from the corresponding partial field of view, the higher the probability of detecting objects and / or the resolution of the lidar sensor in the partial field of view. Advantageously, a scanner device can be provided that enables particularly high performance of the lidar sensor in the partial field of view.

[0021] It is further proposed that the motor be configured to dynamically adjust the rotor angular frequency during the at least one rotation such that the at least one tilt angle subrange extends over a center position of the deflection unit. In particular, the deflection unit is located in the center position within the tilt angle subrange. Preferably, a tilt angle in the center position of the deflection unit corresponds to a center point of the tilt angle subrange.

[0022] Advantageously, a lidar sensor with particularly high performance can be enabled in a central partial field of view.

[0023] It is further proposed that the motor is provided to dynamically adapt the rotor angular frequency in order to change a size and / or a position of the at least one tilt angle sub-range. In particular, the motor is provided to dynamically adapt the rotor angular frequency in order to change the size and / or position of the tilt angle sub-range between movements of the deflection unit in two different tilt directions and / or between two consecutive revolutions of the rotor. The size of the tilt angle sub-range is, in particular, an extension of the tilt angle sub-range. For example, a tilt angle sub-range of 20° is greater than a tilt angle sub-range of 10°. The position of the tilt angle sub-range is, in particular, a position of the tilt angle sub-range within the complete tilt angle range.For example, a tilt angle sub-range from -5° to 5°, which is located within a tilt angle range from -15° to 15°, has a different position than a tilt angle sub-range from 0° to 10° within the tilt angle range, despite being the same size in this case. The size and / or position of the tilt angle sub-range can be changed, in particular, depending on traffic parameters and / or driving parameters. For example, the size of the tilt angle sub-range can be increased depending on approaching road users. For example, the position of the tilt angle sub-range can be changed depending on a change from straight-ahead driving to cornering. In particular, the size and / or position of the corresponding partial field of view of the lidar sensor also changes proportionally to a change in the size and / or position of the tilt angle sub-range.Advantageously, an adaptive partial field of view adjustment of the lidar sensor can be enabled.

[0024] In addition, a computing device for controlling a scanner device according to the invention is proposed. The computing device comprises at least one computing module designed to control the motor of the drive unit of the scanner device such that the motor dynamically adapts a rotor angular frequency during at least one revolution such that a tilt angle speed of the deflection unit of the scanner device is at least substantially constant over at least one tilt angle sub-range. Preferably, the lidar sensor can comprise the computing device. In particular, the computing device can serve for further functions of the lidar sensor, for example, for signal processing. Alternatively, it is conceivable for the computing device to be designed separately from the lidar sensor. For example, a control unit of the vehicle can comprise the computing device.

[0025] The computing module can be designed, in particular, as a microprocessor, as an integrated circuit, in particular as an FPGA (Field Programmable Gate Array) or as an application-specific integrated circuit (ASIC), or the like. In particular, the computing module is provided to determine control signals for controlling the motor. The computing device preferably comprises at least one interface for a signal-transmission coupling of the computing device to the motor. In particular, the interface is provided to provide the control signals determined by the computing module to the motor. The computing module can preferably receive signals from the motor via the interface, in particular for implementing a control loop. The computing module can use optimized rotor angular frequency curves, in particular algorithmically, for example via numerical optimization algorithms or machine learning, to control the motor.

[0026] The computing module is preferably provided to control the motor such that the motor dynamically adjusts the rotor angular frequency during the at least one revolution such that the tilt angle speed of the deflection unit is lower over the at least one tilt angle sub-range than over further tilt angle sub-ranges. The computing module is preferably provided to control the motor such that the motor dynamically adjusts the rotor angular frequency during the at least one revolution such that the at least one tilt angle sub-range extends beyond the center position of the deflection unit. The computing module is preferably provided to control the motor such that the motor dynamically adjusts the rotor angular frequency in order to change the size and / or position of the at least one tilt angle sub-range. Targeted control of the rotor angular frequency can advantageously be enabled.

[0027] A change in the rotor angular frequency, in particular, changes the angular velocity of the crank element. Depending on the angular position, a change in the angular velocity of the crank element can, in particular, correspond to a change in the tilt angular velocity of the deflection unit. The lower the tilt angular velocity over an angular range, the more radiation can be deflected, in particular by the deflection unit, within that angular range. The more radiation can be deflected by the deflection unit within an angular range, the higher the range and / or resolution of the lidar sensor.

[0028] Furthermore, it is proposed that the computing module be configured to control the motor, in particular depending on the situation, based on preset motion profiles and / or current lidar data. The preset motion profiles can be stored, for example, in a memory unit of the computing device. Different motion profiles describe, in particular, different tilting movements of the deflection unit, in particular for different driving and / or traffic situations. For example, a motion profile can be provided for cornering to the right, a motion profile for cornering to the left, a motion profile for driving straight ahead in urban areas, a motion profile for driving straight ahead outside urban areas, and / or other motion profiles that a person skilled in the art deems appropriate.Preferably, the computing module is provided to select a movement profile, particularly one that is appropriate to the situation, in particular depending on the current driving and / or traffic situation, and to control the motor accordingly. Alternatively or additionally, it is conceivable for the computing module to be provided to control the motor depending on current lidar data. For example, the lidar data may indicate that there are a particularly large number of people crossing the road in a partial field of view of the lidar sensor. For example, the computing module can control the motor depending on this lidar data, so that the motor adjusts the size and / or position of the tilt angle sub-range according to the partial field of view. Advantageously, particularly precise control of the scanner device can be enabled.

[0029] It is further proposed that the computing module is provided to control the motor as a function of vehicle parameters, in particular a steering wheel position and / or a vehicle speed. The vehicle parameters can in particular be detected by further sensors of the vehicle and made available to the computing device, for example via a central control unit. For example, the computing module can be provided to control the motor as a function of the steering wheel position in such a way that the motor adapts the position of the tilt angle sub-range in accordance with the steering wheel position. For example, the computing module can be provided to control the motor as a function of the vehicle speed in such a way that the motor adapts the size of the tilt angle sub-range in accordance with the vehicle speed. For example, the size of the tilt angle sub-range can be set to be smaller the higher the vehicle speed.Advantageously, an adaptive control of the scanner device can be enabled.

[0030] Furthermore, a scanner system is proposed. The scanner system comprises at least one scanner device according to the invention. The scanner system comprises at least one computing device according to the invention. Advantageously, a scanner system with ROI functionality can be provided.

[0031] A lidar sensor is also proposed. The lidar sensor comprises at least one scanner device according to the invention or at least one scanner system according to the invention. Advantageously, a lidar sensor with uniform detection quality in at least one partial field of view can be provided.

[0032] Furthermore, a vehicle is proposed. The vehicle comprises at least one lidar sensor according to the invention. The vehicle can in particular also comprise a plurality of lidar sensors according to the invention. The vehicle is preferably designed as an automated vehicle. An "automatically operated vehicle" is to be understood in particular as a vehicle with one of the automation levels 1 to 5 of the SAE J3016 standard. In particular, the automatically operated vehicle has technical equipment required for these automation levels. The technical equipment includes in particular environmental detection sensors, such as radar sensors, the lidar sensor, cameras and / or acoustic sensors, control units, or the like. The vehicle is preferably designed as a land vehicle.The vehicle can be designed, in particular, as a passenger car, preferably as a passenger transport vehicle, in particular an autonomous shuttle, as a truck, as a construction vehicle, as an agricultural vehicle, or as any other vehicle deemed appropriate by a person skilled in the art. Alternatively, the vehicle can also be designed as an aircraft, for example, as a drone, an airplane, a helicopter, a vertical takeoff and landing aircraft, or the like, or as a watercraft, in particular as a ship, a boat, or the like. Advantageously, a particularly roadworthy vehicle can be provided.

[0033] Furthermore, a method for controlling a scanner device according to the invention is proposed. The motor of the drive unit of the scanner device is controlled such that the motor dynamically adjusts a rotor angular frequency during at least one revolution such that a tilt angle speed of the deflection unit of the scanner device is at least substantially constant over at least one tilt angle subrange. Advantageously, a method can be provided that enables uniform detection quality of a lidar sensor in at least one partial field of view.

[0034] The invention is illustrated by an exemplary embodiment in the following figures. They show: Fig. 1 a vehicle according to the invention in a schematic representation, Fig. 2 shows a part of a lidar sensor according to the invention of the vehicle according to the invention Fig. 1 in a schematic representation, Fig. 3 a plan view of a scanner device according to the invention of the lidar sensor according to the invention from Fig. 2 in a schematic representation, Fig. 4 a plan view of the scanner device according to the invention from Fig. 3 in a further schematic representation, Fig. 5 a diagram of an exemplary curve of a crank element angular velocity and a crank element angle in a schematic representation, Fig. 6 a diagram of an exemplary course of a tilt angle speed and a tilt angle in a schematic representation, Fig. 7 a diagram of an exemplary tilt angle speed as a function of a tilt angle in a schematic representation and Fig. 8 a diagram of an alternative exemplary tilt angle speed as a function of a tilt angle in a schematic representation.

[0035] Fig. 1 shows a vehicle 17 in a schematic representation. The vehicle 17 is designed as an automated vehicle. In the present exemplary embodiment, the vehicle 17 is designed, for example, as a land vehicle, in particular as a passenger car. The vehicle 17 comprises at least one lidar sensor 2. The lidar sensor 2 is provided for detecting objects in an environment of the vehicle 17. The lidar sensor 2 has a field of view 18 in which it can detect objects. Fig. 1 shows a horizontal field of view 18 of the lidar sensor 2. In Fig. 1 shows an exemplary partial field of view 31 of the field of view 18.

[0036] Fig. 2 shows a part of the lidar sensor 2 of the vehicle 17 from Fig. 1 in a schematic representation. The lidar sensor 2 comprises at least one scanner system 16. The scanner system 16 comprises at least one scanner device 1. The scanner system 16 comprises at least one computing device 14. The scanner device 1 comprises at least one deflection unit 3 for deflecting radiation, in particular laser radiation. The deflection unit 3 is movably mounted about a rotation axis 4 of the deflection unit 3. The scanner device 1 comprises at least one drive unit 5, which is intended to drive the deflection unit 3. The drive unit 5 has at least one motor 6. The drive unit 5 has at least one crank element 7. In the present exemplary embodiment, the crank element 7 is designed, for example, as a crank disk. The motor 6 is intended to rotate the crank element 7 about a rotation axis 8 of the crank element 7.The drive unit 5 has at least one connecting element 9, which is mounted on the crank element 7 at a first bearing point 10 so as to be rotatably movable and transversely, in particular perpendicularly, offset to the rotational axis 8 of the crank element 7. The connecting element 9 is mounted on the deflection unit 3 at a second bearing point 11 spaced from the first bearing point 10 so as to be rotatably movable and transversely, in particular perpendicularly, offset to the rotational axis 4 of the deflection unit 3.

[0037] In the present exemplary embodiment, the scanner device 1 is provided, for example, to scan laser radiation from a radiation source of the lidar sensor 2 (not shown here) across the field of view 18 of the lidar sensor 2 and to direct radiation reflected back to the lidar sensor 2 in an area surrounding the lidar sensor 2 to a receiving unit of the lidar sensor 2 (not shown here), which is provided, in particular, to detect the reflected radiation. In the present exemplary embodiment, the scanner device 1 is provided, for example, to deflect the radiation in a single plane, here the horizontal field of view 18 of the lidar sensor 2. The lidar sensor 2 can have at least one further scanner device, which is provided to cooperate with the scanner device 1 to realize a scanning of a three-dimensional field of view 18 (not shown here).Alternatively, it is conceivable that the scanner device 1 is provided to deflect a beam of rays, for example a vertical beam of rays, in a single plane, for example a horizontal plane, in particular into the environment and / or to a vertically arranged array of detectors.

[0038] The deflection unit 3 comprises at least one mirror surface 19, which is reflective at least in a wavelength range in which the lidar sensor 2 operates. The mirror surface 19 is intended to reflect radiation incident upon it (cf. Fig. 3). The deflection unit 3 comprises at least one mirror carrier 20, on which the mirror surface 19 is arranged. The mirror carrier 20 is mounted for rotational movement about the rotation axis 4 of the deflection unit 3. The scanner device 1 comprises a carrier unit 21. The scanner device 1 comprises a mirror holder 22. The carrier unit 21 and the mirror holder 22 are provided for mounting the mirror carrier 20 for rotational movement about the rotation axis of the deflection unit 3. The mirror carrier 20 is mounted on a first side on the carrier unit 21 and on a second side, facing away from the first side along the rotation axis 4 of the deflection unit 3, on the mirror holder 22. The two-sided mounting at least reduces unwanted changes in the vertical alignment of the mirror carrier 20. The mirror holder 22 is L-shaped and fixed to the carrier unit 21.

[0039] The rotation axis 4 of the deflection unit 3 extends parallel to the mirror surface 19. The rotation axis 4 of the deflection unit 3 and the mirror surface 19 extend perpendicular to the horizontal field of view 18, in which the scanner device 1, in particular the deflection unit 3, deflects the radiation. The deflection unit 3 deflects radiation impinging on the mirror surface 19 from a specific direction in different directions depending on different angular positions, in particular tilt positions, of the deflection unit 3 about the rotation axis 4 of the deflection unit 3 (see FIG. Fig. 3 and Fig. 4). The field of view 18 that can be scanned by the deflection unit 3 depends on the angular positions of the deflection unit 3 at two reversal points of the deflection unit 3 in different directions of rotation about the rotation axis 4 of the deflection unit 3.

[0040] The motor 6 is designed as an electric motor. The motor 6 is designed as a servomotor. A motor speed of the motor 6 designed as a servomotor is adjustable. In the present exemplary embodiment, the crank element 7 is directly coupled, in particular rotationally fixed, to the motor 6. The crank element 7 is fixed to a drive shaft 23 of the motor 6. The drive shaft 23 of the motor 6 runs parallel, preferably coaxially, to the axis of rotation 8 of the crank element 7. The motor 6 is provided to drive the crank element 7 in a rotation about the axis of rotation 8 of the crank element 7. The axis of rotation 8 of the crank element 7 runs through a center point of the crank element 7 and perpendicular to a main extension plane 24 of the crank element 7. The motor 6 is arranged, in particular fixed, on the support unit 21.

[0041] The connecting element 9 is provided to mechanically couple the crank element 7 and the deflection unit 3 to one another, in particular in terms of power transmission. The crank element 7 and the deflection unit 3 are arranged at a distance from one another. The connecting element 9 is designed as a rod, in particular as a connecting rod. The first bearing point 10 is arranged in a first end region of the connecting element 9. The first bearing point 10 is arranged on the crank element 7 at a radial distance from the axis of rotation 8 of the crank element 7. The connecting element 9 is fastened to the crank element 7 at the first bearing point 10 and can rotate relative to the crank element 7 about a first axis of rotation 12 of the connecting element 9 extending through the first bearing point 10. The second bearing point 11 is arranged in a second end region of the connecting element 9 facing away from the first end region.The second bearing point 11 is arranged radially spaced from the rotational axis 4 of the deflection unit 3 on the deflection unit 3, in particular on the mirror support 20. The connecting element 9 is fastened to the second bearing point 11 on the deflection unit 3, in particular on the mirror support 20, and can rotate about a second rotational axis 13 of the connecting element 9 extending through the second bearing point 11 relative to the deflection unit 3, in particular to the mirror support 20. The rotational axes 4, 8, 12, 13 of the deflection unit 3, the crank element 7, and the connecting element 9 run parallel to one another.

[0042] Due to the eccentric mounting of the connecting element 9 on the crank element 7, a position of the connecting element 9 relative to the rotation axis 4 of the deflection unit 3 changes upon rotation of the crank element 7 depending on an angular position of the crank element 7. Due to the rotationally movable mounting of the deflection unit 3 about the rotation axis 4 of the deflection unit 3 and the eccentric mounting of the connecting element 9 on the deflection unit 3, a tilting movement of the deflection unit 3 about the rotation axis 4 of the deflection unit 3 results depending on a change in position of the connecting element 9 relative to the rotation axis 4 of the deflection unit 3. The deflection unit 3 tilts during one revolution, in particular a 360° rotation, of the crank element 7 from a first reversal point to a second reversal point and back again.Due to the design of the drive unit 5 and the deflection unit 3, a rotation of the crank element 7 can be converted into a tilting of the deflection unit 3. The size of the field of view 18 scanned by the scanner device 1, in particular a maximum tilting of the deflection unit 3, can be adjusted by changing a diameter of the crank element 7, a length of the connecting element 9, a position of the first bearing point 10 on the crank element 7, and a position of the second bearing point 11 on the deflection unit 3, in particular on the mirror carrier 20.

[0043] The motor 6 is provided to rotate the crank element 7 about the rotation axis 8 of the crank element 7 in order to generate an oscillatory tilting of the deflection unit 3 about the rotation axis 4 of the deflection unit 3. The motor 6 is provided to dynamically adapt a rotor angular frequency during at least one revolution such that a tilting angle speed of the deflection unit 3 is at least substantially constant over at least one tilting angle sub-range 28. The motor 6 is provided to dynamically adapt the rotor angular frequency during the rotation such that the tilting angle speed of the deflection unit 3 is at least substantially constant over the tilting angle sub-range 28, independent of a tilting direction of the deflection unit 3, in particular both during a tilting movement of the deflection unit 3 from the first reversal point to the second reversal point and from the second reversal point to the first reversal point (cf. Fig. 6). The motor 6 is provided to dynamically adjust the rotor angular frequency during the rotation such that the tilt angle speed of the deflection unit 3 is at least almost constant over the tilt angle sub-range 28. The motor 6 is provided to keep the rotor angular frequency at least substantially constant while the deflection unit 3 moves over the tilt angle sub-range 28. The tilt angle sub-range 28 is proportional to the partial field of view 31 of the lidar sensor 2. The scanner device 1 scans the radiation while the deflection unit 3 moves over the tilt angle sub-range 28 at an at least substantially constant speed over the partial field of view 31. The motor 6 is provided to dynamically adjust the rotor angular frequency during the at least one rotation such that the at least one tilt angle sub-range 28 extends over a central position of the deflection unit 3 (cf. Fig. 3).

[0044] The computing device 14 is provided for controlling the scanner device 1. The computing device 14 comprises at least one computing module 15, which is provided for controlling the motor 6 of the drive unit 5 of the scanner device 1 such that the motor 6 dynamically adjusts the rotor angular frequency during the at least one revolution such that the tilt angle speed of the deflection unit 3 of the scanner device 1 is at least substantially constant over the at least one tilt angle subrange 28. In the present exemplary embodiment, the lidar sensor 2 comprises the computing device 14, for example.

[0045] The computing module 15 is provided for determining control signals for controlling the motor 6. The computing device 14 comprises at least one interface 26 for a signal-transmitting coupling of the computing device 14 to the motor 6. The interface 26 is provided for providing the control signals determined by the computing module 15 to the motor 6. The computing module 15 can receive signals from the motor 6 via the interface 26, in particular for implementing a control loop. A signal from the motor 6 can, for example, be an actual position of a rotation angle of the crank element 7. The computing module 15 can use optimized rotor angular frequency curves algorithmically, for example via numerical optimization algorithms or machine learning, to control the motor 6.

[0046] A change in the rotor angular frequency changes the angular velocity of the crank element 7. Depending on the angular position, a change in the angular velocity of the crank element 7 can correspond to a change in the tilt angular velocity of the deflection unit 3. The lower the tilt angular velocity over an angular range, the more radiation can be deflected by the deflection unit 3 within that angular range. The more radiation can be deflected by the deflection unit 3 within an angular range, the higher the range and / or resolution of the lidar sensor 2.

[0047] Fig. 3 shows a top view of the scanner device 1 of the lidar sensor 2 from Fig. 2 in a schematic representation. The deflection unit 3 is shown in the center position, between the two reversal points during the tilting movement. Radiation, represented here by a laser beam 27, from the laser source or from the surroundings of the lidar sensor 2 strikes the mirror surface 19 and is deflected in a specific direction.

[0048] Fig. 4 shows a plan view of the scanner device 1 from Fig. 3 in another schematic representation. Compared to the representation in Fig. 3, the crank element 7 has rotated 90° or a quarter revolution in the direction of rotation 25. The deflection unit 3 is in comparison to the illustration in Fig. 3 tilted. The deflection unit 3 is deflected to its maximum along a tilt direction. The deflection unit 3 is located at a reversal point. The deflection unit 3 is deflected from the same direction as in Fig. 3 laser beam 27 impinging on the mirror surface 19 is deflected in a different direction due to the changed position of the deflection unit 3.

[0049] Fig. 5 shows a diagram of an exemplary curve of a crank element angular velocity and a crank element angle in a schematic representation. The diagram comprises an abscissa axis 32 on which a time is plotted. The diagram comprises an ordinate axis 33 on which the crank element angle and the crank element velocity are plotted. The crank element angle is shown as an example in a range from 0° to 360°, in particular for one revolution of the crank element 7. The crank element angular velocity is shown as an example such that a minimum displayed crank element angular velocity corresponds to approximately one-third of a maximum displayed crank element angular velocity. A zero position 36 of the tilt angle corresponding to a center position of the deflection unit 3 is marked. Lines 39 indicate the reversal points. A first curve 34 represents the curve of the crank element angular velocity.A second curve 35 represents the course of the crank element angle. A diagram from . Fig. 5 The underlying engine speed curve can, for example, be numerically optimized. The engine speed corresponds to the crank element angular velocity.

[0050] Fig. 6 shows a diagram of an exemplary course of a tilt angle velocity and a tilt angle in a schematic representation. The diagram comprises an abscissa axis 32', on which a time is plotted. The diagram comprises an ordinate axis 33', on which the tilt angle and the tilt angle velocity are plotted. A zero position 36' of the tilt angle corresponding to a center position of the deflection unit 3 is marked. Lines 39' mark the reversal points. A first curve 34' represents the temporal course of the tilt angle velocity at Fig. 5 modulated crank element angular velocity or rotor angular frequency. A second curve 35' represents the temporal course of the tilt angle at Fig. 5 modulated crank element angular velocity or rotor angular frequency. A third curve 37' represents the temporal course of the tilt angular velocity at a constant crank element angular velocity or rotor angular frequency. A fourth curve 38' represents the temporal course of the tilt angle at a constant crank element angular velocity or rotor angular frequency. In the region of zero crossings of the tilt angle (center position of the deflection unit 3), the modulation of the rotor angular frequency results in lower and at least essentially constant tilt angular velocities over the tilt angle sub-range 28 compared to the constant rotor angular frequency.

[0051] Fig. Figure 7 shows a diagram of an exemplary tilt angle velocity as a function of a tilt angle in a schematic representation. The diagram comprises an abscissa axis 32", on which the tilt angle is plotted. A zero position 36" of the tilt angle corresponding to the center position of the deflection unit is marked. Lines 39" mark the reversal points. The diagram comprises an ordinate axis 33", on which the tilt angle velocity is plotted. A first curve 34" represents the course of the tilt angle velocity at Fig. 5 modulated crank element angular velocity or rotor angular frequency. A second curve 35" represents the course of the tilt angular velocity at a constant, in particular non-modulated, motor speed, in particular crank element angular velocity. The motor 6 is provided to dynamically adapt the rotor angular frequency during the rotation in such a way that the tilt angular velocity of the deflection unit 3 over the at least one tilt angle sub-range 28 is lower than over further tilt angle sub-ranges 29, 30. The motor 6 is provided to dynamically adapt the rotor angular frequency during the rotation in such a way that the tilt angular velocity of the deflection unit 3 over the tilt angle sub-range 28 is lower than as a function of a constant rotor angular frequency.

[0052] Fig. Figure 8 shows a diagram of an alternative exemplary tilt angle velocity as a function of a tilt angle in a schematic representation. The diagram comprises an abscissa axis 32''', on which the tilt angle is plotted. A zero position 36''' of the tilt angle corresponding to the center position of the deflection unit is marked. Lines 39''' mark the reversal points. The diagram comprises an ordinate axis 33''', on which the tilt angle velocity is plotted. A first curve 34''' represents the course of the tilt angle velocity at Fig. 5 modulated crank element angular velocity or rotor angular frequency. A second curve 35''' represents the course of the tilt angular velocity at a constant, in particular non-modulated, engine speed, in particular crank element angular velocity.

[0053] The motor 6 is provided to dynamically adjust the rotor angular frequency in order to change a size and / or a position of the at least one tilt angle sub-range 28. The motor 6 is provided to dynamically adjust the rotor angular frequency in order to change the size and / or position of the tilt angle sub-range 28 between movements of the deflection unit 3 in two different tilt directions and / or between two consecutive revolutions of the rotor. In the present exemplary embodiment, the size of the tilt angle sub-range 28 has changed between two consecutive revolutions of the rotor. A first revolution is in Fig. 7 and a subsequent rotation in Fig. 8. The position of the tilt angle sub-range 28, in particular a center of the tilt angle sub-range 28, is in the Fig. 8 unchanged compared to Fig. 7. The tilt angle range 28 is in the Fig. 8 larger than in the Fig. 7. In the Fig. 7, the tilt angle range 28 comprises approximately 12° and in the Fig. 8 approx. 16°.

[0054] The computing module 15 is designed to control the motor 6, particularly depending on the situation, depending on preset movement profiles and / or current lidar data. For example, it is possible to switch between the display in the Fig. 7 and the representation in the Fig. 8 from a movement profile for a straight-ahead drive outside of town to a movement profile for a straight-ahead drive in town. For example, you can switch between the display in the Fig. 7 and the representation in the Fig. 8 additional road users may have joined outside the original partial field of vision 31.

[0055] The computing module 15 is designed to control the motor 6 depending on vehicle parameters, in particular a steering wheel position and / or a vehicle speed. For example, there may be a difference between the representation in the Fig. 7 and the representation in the Fig. 8 have reduced the vehicle speed.

[0056] In a method for controlling the scanner device 1, the motor 6 of the drive unit 5 of the scanner device 1 is controlled such that the motor 6 dynamically adapts a rotor angular frequency during at least one revolution such that a tilt angle speed of the deflection unit 3 of the scanner device 1 is at least substantially constant over at least one tilt angle subrange 28. Reference symbol 1 scanner device 2 Lidar sensors 3 Deflection unit 4 rotation axis 5 Drive unit 6 Engine 7 Crank element 8 Rotation axis 9 Connecting element 10 bearing point 11 bearing point 12 Rotation axis 13 Rotation axis 14 Calculating device 15 Calculation module 16 scanner system 17 vehicles 18 field of view 19 Mirror surface 20 mirror supports 21 carrier unit 22 mirror holders 23 Drive shaft 24 Main extension level 25 Direction of rotation 26 Interface 27 Laser beam 28 Tilt angle subrange 29 Tilt angle subrange 30 Tilt angle subrange 31 partial field of view 32 abscissa axis 33 Ordinate axis 34 Curve 35 Curve 36 Zero position 37 Curve 38 Curve 39 Line

Claims

[1] A scanner device, in particular for a lidar sensor (2), comprising at least one deflection unit (3) for deflecting radiation, in particular laser radiation, wherein the deflection unit (3) is mounted so as to be movable about a rotational axis (4) of the deflection unit (3), and at least one drive unit (5) which is provided for driving the deflection unit (3) to perform a tilting movement about the rotational axis (4) of the deflection unit (3), wherein the drive unit (5) has at least one motor (6) and at least one crank element (7), wherein the motor (6) is provided for rotating the crank element (7) about a rotational axis (8) of the crank element (7), wherein the drive unit (5) has at least one connecting element (9) which is mounted on the crank element (7) at a first bearing point (10) so as to be rotatably movable and transversely, in particular perpendicularly, offset to the rotational axis (8) of the crank element (7),and which is mounted on the deflection unit (3) at a second bearing point (11) spaced apart from the first bearing point (10) so as to be rotatably movable and transversely, in particular perpendicularly, offset to the rotational axis (4) of the deflection unit (3), wherein the motor (6) is provided to dynamically adapt a rotor angular frequency during at least one revolution such that a tilt angle speed of the deflection unit (3) is at least substantially constant over at least one tilt angle sub-range (28). [2] Scanner device according to claim 1, wherein the motor (6) is provided to dynamically adapt the rotor angular frequency during the at least one revolution such that the tilt angle speed of the deflection unit (3) is lower over the at least one tilt angle sub-range (28) than over further tilt angle sub-ranges (29, 30). [3] Scanner device according to claim 1 or 2, wherein the motor (6) is provided to dynamically adapt the rotor angular frequency during the at least one revolution such that the at least one tilt angle sub-range (28) extends over a central position of the deflection unit (3). [4] Scanner device according to one of the preceding claims, wherein the motor (6) is provided to dynamically adapt the rotor angular frequency in order to change a size and / or a position of the at least one tilt angle sub-range (28). [5] Computing device for controlling a scanner device (1) according to one of the preceding claims, comprising at least one computing module (15) which is provided to control the motor (6) of the drive unit (5) of the scanner device (1) in such a way that the motor (6) dynamically adapts a rotor angular frequency during at least one revolution in such a way that a tilt angle speed of the deflection unit (3) of the scanner device (1) is at least substantially constant over at least one tilt angle partial range (28). [6] Computing device according to claim 5, wherein the computing module (15) is provided to control the motor (6), in particular depending on the situation, depending on preset movement profiles and / or current lidar data. [7] Computing device according to claim 5 or 6, wherein the computing module (15) is provided to control the motor (6) as a function of vehicle parameters, in particular a steering wheel position and / or a vehicle speed. [8] Scanner system comprising at least one scanner device (1) according to one of claims 1 to 4 and at least one computing device (14) according to one of claims 5 to 7. [9] Lidar sensor comprising at least one scanner device (1) according to one of claims 1 to 4 or at least one scanner system (16) according to claim 8. [10] Vehicle comprising at least one lidar sensor (2) according to claim 9. [11] Method for controlling a scanner device (1) according to one of claims 1 to 4, wherein the motor (6) of the drive unit (5) of the scanner device (1) is controlled such that the motor (6) dynamically adapts a rotor angular frequency during at least one revolution such that a tilt angle speed of the deflection unit (3) of the scanner device (1) is at least substantially constant over at least one tilt angle partial range (28).

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