New photoelectric body position sensor

Abstract

The present invention provides a novel photoelectric vehicle body position sensor, which comprises a first cylinder (11), a second cylinder (21), a first piston (12), a second piston (22), a first photoelectric detection module (13), a second photoelectric detection module (23), a vehicle body (4), a lower cantilever (5), a connecting component (6) and a differential amplifier (7), wherein the first photoelectric detection module (13) comprises a first light source driver (131), a first light source (132), a first photoelectric detector (133), a first readout circuit (134) and a first temperature sensor (135), wherein the second photoelectric detection module (23) comprises a second light source driver (231), a second light source (232), a second photoelectric detector (233), a second readout circuit (234) and a second temperature sensor (235). The present invention can be used for measuring the position of a vehicle body and a lower cantilever, and can be widely used in the automotive field.

Description

Technical Field

[0001] The present invention relates to a novel photoelectric vehicle body position sensor, which can be widely used in the automotive field and belongs to the automotive electronic technology field. Background Art

[0002] The automotive active suspension system is a new type of suspension system developed in the past decade and controlled by the automotive electronic control unit (ECU). The system has the function of controlling the vibration and height of the vehicle body, and can mainly improve the vehicle's operational stability, ride comfort and other performance. When the vehicle is driving on an undulating road or the inertia during braking causes the shock absorber in the suspension system to deform, the active suspension system will generate a force that counteracts the inertia to reduce the change in the vehicle body position.

[0003] The active suspension system of a car usually consists of the following parts: body position sensor, electronic control unit, power source and actuator that generates force and torque. The body position sensor detects the change in body height (the displacement between the body and the lower cantilever) and converts it into an electrical signal to feed back to the active suspension electronic control unit. The electronic control unit processes the displacement and controls the actuator to adjust the body height to keep the body stable.

[0004] The present invention discloses a novel photoelectric vehicle body position sensor. The system can be used to measure the position of the vehicle body and the lower cantilever, and can be widely used in the automotive field. The sensor is based on photoelectric measurement technology. In the system, dual measurement channels are reversely installed between the vehicle body and the lower cantilever. The displacement change of the vehicle body will cause the photoelectric detectors in the two measurement channels to receive a relative change in light intensity, and then the readout circuit generates a relatively changed electrical signal. Finally, the relatively changed electrical signal is processed by a differential amplifier, which can avoid the influence of ambient light and temperature on the measurement result. Summary of the invention

[0005] The purpose of the present invention is to provide a novel photoelectric body position sensor. The system can be used to measure the position of the automobile body and the lower cantilever, and can be widely used in the automobile field.

[0006] A novel photoelectric vehicle body position sensor comprises a first cylinder (11), a second cylinder (21), a first piston (12), a second piston (22), a first photoelectric detection module (13), a second photoelectric detection module (23), a vehicle body (4), a lower cantilever (5), a connecting component (6) and a differential amplifier (7), wherein the first photoelectric detection module (13) comprises a first light source driver (131), a first light source (132), a first photoelectric detector (133), a first readout circuit (134) and a first temperature sensor (135), and wherein the second photoelectric detection module (23) comprises a second light source driver (231), a second light source (232), a second photoelectric detector (233), a second readout circuit (234) and a second temperature sensor (235).

[0007] The present invention is implemented as follows: the first cylinder (11) and the second piston (22) are fixed to the vehicle body (4) through a connecting component (6), and the first piston (12) and the second cylinder (21) are fixed to the lower cantilever (5) through a connecting component (6); a first photoelectric detection module (13) and a second photoelectric detection module (23) are respectively placed on the top of the first cylinder (11) and the second cylinder (21); in the first photoelectric detection module (13), a first light source driver (131) is connected to and drives the first light source (132) to emit a light signal to the upper surface of the first piston (12), and the light signal is reflected to the first photoelectric detector (133) for photoelectric conversion, and the first reader The output circuit (134) is connected to the first photodetector (133) and converts the photocurrent signal outputted by the first photodetector into a voltage signal, and the output voltage signal is outputted to the inverting input terminal of the differential amplifier (7); in the second photodetection module (23), the second light source driver (231) is connected to and drives the second light source (232) to emit a light signal to the upper surface of the second piston (22), and the light signal is reflected to the second photodetector (233) for photoelectric conversion, and the second readout circuit (234) is connected to the second photodetector (233) and converts the photocurrent signal outputted by the second photodetector into a voltage signal, and the output voltage signal is outputted to the non-inverting input terminal of the differential amplifier (7).

[0008] The first piston (12) and the second piston (22) slide up and down in the first cylinder (11) and the second cylinder (21) respectively; when the vehicle body (4) and the lower cantilever (5) are separated, the distance between the first piston (12) and the top of the first cylinder (11) increases, and the distance between the second piston (22) and the top of the second cylinder (21) decreases; when the vehicle body (4) and the lower cantilever (5) are close, the distance between the first piston (12) and the top of the second cylinder (21) decreases, and the distance between the second piston (22) and the top of the second cylinder (21) increases.

[0009] The first light source (132) and the second light source (232) are based on laser diodes or light-emitting diodes, and the first photodetector (133) and the second photodetector (233) are based on photodiodes; the first temperature sensor (135) and the second temperature sensor (235) monitor the temperature in the cylinder in real time, and compensate the first light source driver (131), the second light source driver (231), the first readout circuit (134) and the second readout circuit (234) for the influence caused by temperature changes according to the temperature.

[0010] The upper surfaces of the first piston (12) and the second piston (22) are covered with a diffuse reflection medium. A first light source (132) located at the top of the first cylinder (11) and a second light source (232) located at the top of the second cylinder (21) irradiate light in the direction of the pistons. The light is reflected by the diffuse reflection medium and received by a first photodetector (133) located at the top of the first cylinder (11) and a second photodetector (233) located at the top of the second cylinder (21). The intensity of the received light is related to the distance from the upper surface of the piston to the top of the cylinder. The received light intensity decreases as the distance increases. The change in distance can be detected by detecting the change in light intensity.

[0011] The first readout circuit (134) is connected to the inverting input terminal of the differential amplifier, and the second readout circuit (234) is connected to the non-inverting input terminal of the amplifier; when the vehicle body (4) is separated from the lower cantilever (5), the light intensity received by the first photodetector (133) decreases while the light intensity received by the second photodetector (233) increases; when the vehicle body (4) is close to the lower cantilever (5), the light intensity received by the first photodetector (133) increases while the light intensity received by the second photodetector (233) decreases; the change in the distance between the vehicle body (4) and the lower cantilever (5) causes a relative change in the light intensity received by the first photodetector (133) and the second photodetector (233), thereby causing a relative change in the output voltage signals of the first readout circuit (134) and the second readout circuit (234); the differential amplifier (7) amplifies the input relative change signal and outputs it. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1The invention is a schematic diagram of a novel photoelectric vehicle body position sensor. The sensor comprises a first cylinder (11), a second cylinder (21), a first piston (12), a second piston (22), a first photoelectric detection module (13), a second photoelectric detection module (23), a vehicle body (4), a lower cantilever (5), a connecting component (6) and a differential amplifier (7), wherein the first photoelectric detection module (13) comprises a first light source driver (131), a first light source (132), a first photoelectric detector (133), a first readout circuit (134) and a first temperature sensor (135), and the second photoelectric detection module (23) comprises a second light source driver (231), a second light source (232), a second photoelectric detector (233), a second readout circuit (234) and a second temperature sensor (235).

[0013] Figure 2 The invention is a schematic diagram of an embodiment of a novel photoelectric vehicle body position sensor. The sensor comprises a first cylinder (11), a second cylinder (21), a first piston (12), a second piston (22), a first photoelectric detection module (13), a second photoelectric detection module (23), a vehicle body (4), a lower cantilever (5), a connecting component (6) and a differential amplifier (7), wherein the first photoelectric detection module (13) comprises a first light source driver (131), a first light source (132), a first photoelectric detector (133), a first readout circuit (134) and a first temperature sensor (135), and wherein the second photoelectric detection module (23) comprises a second light source driver (231), a second light source (232), a second photoelectric detector (233), a second readout circuit (234) and a second temperature sensor (235). DETAILED DESCRIPTION

[0014] The present invention will be further described below in conjunction with specific embodiments.

[0015] Figure 2A novel photoelectric vehicle body position sensor embodiment is provided, wherein a first cylinder (11) and a second piston (22) are fixed to a vehicle body (4) via a connecting component (6), and the first piston (12) and the second cylinder (21) are fixed to a lower cantilever (5) via a connecting component (6). A first photoelectric detection module (13) and a second photoelectric detection module (23) are respectively placed on the top of the first cylinder (11) and the second cylinder (21). In the first photoelectric detection module (13), the first light source driver (131) is connected to and drives the first light source (132) to emit a light signal to the upper surface of the first piston (12), the light signal is reflected to the first photodetector (133) for photoelectric conversion, the first readout circuit (134) is connected to the first photodetector (133) and converts the photocurrent signal outputted by the first photodetector into a voltage signal, and the output voltage signal is output to the inverting input terminal of the differential amplifier (7); in the second photoelectric detection module (23), the second light source driver (231) is connected to and drives the second light source (232) to emit a light signal to the upper surface of the second piston (22), the light signal is reflected to the second photodetector (233) for photoelectric conversion, the second readout circuit (234) is connected to the second photodetector (233) and converts the photocurrent signal outputted by the second photodetector into a voltage signal, and the output voltage signal is output to the non-inverting input terminal of the differential amplifier (7).

[0016] The first piston (12) and the second piston (22) can slide up and down in the first cylinder (11) and the second cylinder (21) respectively. When the vehicle body (4) and the lower cantilever (5) are separated, the distance between the first piston (12) and the top of the first cylinder (11) increases, and the distance between the second piston (22) and the top of the second cylinder (21) decreases. When the vehicle body (4) and the lower cantilever (5) are close, the distance between the first piston (12) and the top of the second cylinder (21) decreases, and the distance between the second piston (22) and the top of the second cylinder (21) increases. The first light source (132) and the second light source (232) are laser diodes, and the first photoelectric detector (133) and the second photoelectric detector (233) are photoelectric diodes. The first temperature sensor (135) and the second temperature sensor (235) monitor the temperature in the cylinder in real time, and compensate the first light source driver (131), the second light source driver (231), the first readout circuit (134) and the second readout circuit (234) for the influence caused by temperature change according to the temperature. The upper surfaces of the first piston (12) and the second piston (22) are covered with diffuse reflection medium. The first light source (132) located at the top of the first cylinder (11) and the second light source (232) located at the top of the second cylinder (21) irradiate light toward the piston. The light is reflected by the diffuse reflection medium and received by the first photodetector (133) located at the top of the first cylinder (11) and the second photodetector (233) located at the top of the second cylinder (21). The intensity of the received light is related to the distance from the upper surface of the piston to the top of the cylinder. The received light intensity decreases as the distance increases. The change in the distance can be detected by detecting the change in light intensity. The first readout circuit (134) is connected to the inverting input terminal of the differential amplifier, and the second readout circuit (234) is connected to the non-inverting input terminal of the amplifier. When the vehicle body (4) is separated from the lower cantilever (5), the light intensity received by the first photodetector (133) decreases while the light intensity received by the second photodetector (233) increases. When the vehicle body (4) is close to the lower cantilever (5), the light intensity received by the first photodetector (133) increases while the light intensity received by the second photodetector (233) decreases. The change in the distance between the vehicle body (4) and the lower cantilever (5) causes a relative change in the light intensity received by the first photodetector (133) and the second photodetector (233), which in turn causes a relative change in the output voltage signal of the first readout circuit (134) and the second readout circuit (234). The differential amplifier (7) amplifies and outputs the input relative change signal. The differential amplifier (7) only amplifies the electrical signal of the relative change caused by the movement of the vehicle body (4) and the lower cantilever (5). The signals caused by ambient light and temperature are common mode signals and will not be amplified.

Claims

1. A novel photoelectric vehicle body position sensor, comprising a first cylinder, a second cylinder, a first piston, a second piston, a first photoelectric detection module, a second photoelectric detection module, a vehicle body, a lower cantilever, a connecting component and a differential amplifier, wherein the first photoelectric detection module is driven by a first light source, a first light source, a first photoelectric detector, a first readout circuit and a first temperature sensor, and the second photoelectric detection module is driven by a second light source, a second light source, a second photoelectric detector, a second readout circuit and a second temperature sensor; the first cylinder and the second piston are fixed to the vehicle body by a connecting component, and the first piston and the second cylinder are fixed to the lower cantilever by a connecting component; the first photoelectric detection module and the second photoelectric detection module are respectively placed on the top of the first cylinder and the second cylinder; In the first photoelectric detection module, the first light source driver is connected and drives the first light source to emit a light signal to the upper surface of the first piston, the light signal is reflected to the first photodetector for photoelectric conversion, the first readout circuit is connected to the first photodetector and converts the photocurrent signal output by the first photodetector into a voltage signal, and the output voltage signal is output to the inverting input terminal of the differential amplifier; In the second photoelectric detection module, the second light source driver is connected and drives the second light source to emit a light signal to the upper surface of the second piston. The light signal is reflected to the second photodetector for photoelectric conversion. The second readout circuit is connected to the second photodetector and converts its output photocurrent signal into a voltage signal. The output voltage signal is output to the in-phase input terminal of the differential amplifier.

2. The novel photoelectric vehicle body position sensor according to claim 1 is characterized in that: The first piston and the second piston slide up and down in the first cylinder body and the second cylinder body respectively; when the vehicle body and the lower cantilever are separated, the distance between the first piston and the top of the first cylinder body increases, and the distance between the second piston and the top of the second cylinder body decreases; when the vehicle body and the lower cantilever are close, the distance between the first piston and the top of the second cylinder body decreases, and the distance between the second piston and the top of the second cylinder body increases.

3. The novel photoelectric vehicle body position sensor according to claim 1 is characterized in that: The first light source and the second light source are based on laser diodes or light-emitting diodes, and the first photodetector and the second photodetector are based on photodiodes; the first temperature sensor and the second temperature sensor monitor the temperature inside the cylinder in real time, and drive the first light source, the second light source, the first readout circuit and the second readout circuit according to the temperature to compensate for the impact of temperature changes.

4. The novel photoelectric vehicle body position sensor according to claim 1 is characterized in that: The upper surfaces of the first piston and the second piston are covered with a diffuse reflection medium. The first light source located at the top of the first cylinder body and the second light source located at the top of the second cylinder body irradiate light toward the piston. The light is reflected by the diffuse reflection medium and received by the first photodetector located at the top of the first cylinder body and the second photodetector located at the top of the second cylinder body. The intensity of the received light is related to the distance from the upper surface of the piston to the top of the cylinder body. The received light intensity decreases as the distance increases, and the distance change is obtained by detecting the change in light intensity.

5. The novel photoelectric vehicle body position sensor according to claim 1 is characterized in that: The first readout circuit is connected to the inverting input terminal of the differential amplifier, and the second readout circuit is connected to the non-inverting input terminal of the amplifier; when the vehicle body is separated from the lower cantilever, the light intensity received by the first photodetector decreases while the light intensity received by the second photodetector increases, and when the vehicle body is close to the lower cantilever, the light intensity received by the first photodetector increases while the light intensity received by the second photodetector decreases; the change in the distance between the vehicle body and the lower cantilever will cause a relative change in the light intensity received by the first photodetector and the second photodetector, and then cause a relative change in the output voltage signals of the first readout circuit and the second readout circuit, and the differential amplifier amplifies and outputs the input relative change signal.

Images