A method, system and lidar for preventing condensation in optical devices

Abstract

This application provides a method, system, and lidar for preventing condensation or oil buildup in optical devices, relating to the field of optical device or lidar technology. The method includes at least one of the following: controlling the activation of a condensation module when the temperature of the motor module is higher than an upper limit temperature value; calculating a lower limit temperature value based on the temperature and humidity of the optical module, and controlling the activation of the condensation module when the temperature of the condensation module is lower than the lower limit temperature value. Activating the condensation module when a risk of condensation or oil buildup is determined allows oil or water to condense on the condensation module, thereby preventing condensation on the optical module and preventing fogging or oil contamination from affecting optical performance.

Description

Technical Field

[0001] This application relates to the field of optical devices or lidar technology, and in particular to methods and systems for preventing condensation in optical devices. Background Technology

[0002] As a high-precision optical instrument, the cleanliness of the surfaces of LiDAR's internal optical components (including lasers, prisms, mirrors, and receiving lenses) directly affects the performance indicators of point clouds. The applicant has identified the following issues:

[0003] 1. The grease and other lubricating materials in the bearings inside the lidar system evaporate during the long-term aging process and high-temperature process, adhering to the surface of optical devices and affecting the point cloud quality, such as range attenuation.

[0004] 2. In extreme climatic environments, condensation and fogging may occur on the internal optical components of lidar, which affects optical performance.

[0005] Therefore, how to prevent condensation or oil buildup on optical components is a technical problem that needs to be solved. Summary of the Invention

[0006] The purpose of this application is to provide a method, system, and lidar for preventing condensation on optical devices, thereby solving the technical problem of how to prevent condensation on optical devices in the prior art. In this application, the term "condensation" refers to either condensed water or condensed oil.

[0007] To achieve the above objectives, the embodiments of this application adopt the following technical solutions.

[0008] In a first aspect, embodiments of this application provide an anti-condensation system for optical devices, including a motor module, an optical module, a temperature control module, and a condensation module; the temperature control module is electrically connected to the motor module, the optical module, and the condensation module respectively;

[0009] The temperature control module has at least one of the following functions: controlling the condenser module to start when the temperature of the motor module is higher than the upper limit temperature value; calculating the lower limit temperature value based on the temperature and humidity of the optical module, and controlling the condenser module to start when the temperature of the condenser module is lower than the lower limit temperature value.

[0010] Optionally, the condensation module includes a first sensor for detecting temperature, which represents the temperature of the condensation module.

[0011] The optical module includes a second sensor and a third sensor. The second sensor is used to detect temperature, which represents the temperature of the optical module. The third sensor is used to detect humidity, which represents the humidity of the optical module.

[0012] The motor module includes a fourth sensor for detecting temperature, which represents the temperature of the motor module.

[0013] Optionally, the condensation module includes a semiconductor cooling chip and a condenser plate;

[0014] The steps of the temperature control module controlling the start of the condenser module include: controlling the start of the semiconductor cooling chip to reduce the temperature of the condenser plate.

[0015] Optionally, the temperature control module is used to control the condenser module to stop when the temperature of the motor module is higher than the upper limit temperature value, and the temperature of the motor module drops to the first normal temperature value after the condenser module is started.

[0016] Optionally, the temperature control module is used to control the condensation rate of the condensation module to slow down or stop when the temperature of the condensation module is lower than the lower limit temperature value, or when the condensation module is started and the slowdown or stop conditions are met.

[0017] Optionally, the condensation module includes a condenser plate and at least one semiconductor refrigeration chip;

[0018] The steps of the temperature control module to control the condensation speed of the condensation module to slow down include: controlling the duty cycle of the drive signal of the thermoelectric cooler to decrease, or reducing the number of thermoelectric coolers in operation.

[0019] Secondly, embodiments of this application provide an anti-condensation method for optical devices, applied to a temperature control module in the anti-condensation system for optical devices of the first aspect, wherein the operation of the temperature control module includes at least one of the following:

[0020] When the temperature of the motor module exceeds the upper limit temperature value, the condenser module is controlled to start.

[0021] Based on the temperature and humidity of the optical module, a lower limit temperature value is calculated, and the condenser module is activated when its temperature is lower than the lower limit temperature value.

[0022] Optionally, the condensation module includes a semiconductor cooling chip and a condenser plate;

[0023] The steps for controlling the start-up of the condensation module include: controlling the start-up of the semiconductor cooling chip to reduce the temperature of the condensation plate.

[0024] Optionally, the method for preventing condensation on the optical device further includes:

[0025] When the temperature of the motor module is higher than the upper limit temperature value and the condenser module is started, and the temperature of the motor module drops to the first normal temperature value, the condenser module is controlled to stop.

[0026] Optionally, the method for preventing condensation on the optical device further includes:

[0027] When the temperature of the condensing module is lower than the lower limit temperature value, and the condensing module is started, and the slowdown or stop conditions are met, the condensing rate of the condensing module is controlled to slow down or stop.

[0028] Thirdly, embodiments of this application provide a lidar, including the optical device anti-condensation system of the first aspect.

[0029] Compared with the prior art, this application has the following advantages:

[0030] The optical device anti-condensation method, system, and lidar provided in this application activate the condensation module when a condensation risk is detected, causing oil or water to condense on the condensation module, thereby preventing condensation on the optical module and preventing fogging from affecting optical performance. Attached Figure Description

[0031] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 A schematic diagram of an anti-condensation system for an optical device provided in this application embodiment;

[0033] Figure 2 A schematic diagram of an optical device anti-condensation system for a condensation module including a semiconductor cooling chip and a condensation plate is provided for an embodiment of this application;

[0034] Figure 3 A schematic diagram of the location of a condenser module provided in an embodiment of this application;

[0035] Figure 4 This is a schematic diagram of an anti-condensation system for optical devices with a circuit board assembly, provided as an embodiment of this application.

[0036] Explanation of reference numerals in the attached figures:

[0037] 10-Condensation Module

[0038] 11-First Sensor

[0039] 12-Semiconductor Cooler

[0040] 13-Condensing Plate

[0041] 20-Optical Module

[0042] 21-Second Sensor

[0043] 22-Third Sensor

[0044] 30-Motor Module

[0045] 31-Fourth Sensor

[0046] 40-Temperature control module

[0047] 50-Circuit Board Assembly Detailed Implementation

[0048] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. The described embodiments are only some embodiments of this application, not all embodiments. The components of the embodiments of this application described in the accompanying drawings can generally be arranged and designed in various different configurations.

[0049] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0050] In the description of this application, it should be noted that relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. The term "connection" should be interpreted broadly, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium.

[0051] Existing lidar or other optical instruments suffer from fogging, which affects their optical performance.

[0052] To avoid fogging issues, please refer to... Figure 1 This application provides an anti-condensation system for optical devices, including a condensation module 10, an optical module 20, a motor module 30, and a temperature control module 40.

[0053] The temperature control module 40 has at least one of the following functions: when the temperature of the motor module 30 is higher than the upper limit temperature value, it controls the condenser module 10 to start; based on the temperature and humidity of the optical module 20, it calculates the lower limit temperature value and controls the condenser module 10 to start when the temperature of the condenser module 10 is lower than the lower limit temperature value.

[0054] Figure 1 An example of setting up sensors to detect various temperature and humidity parameters is given:

[0055] The condensation module 10 includes a first sensor 11, which is used to detect temperature, representing the temperature of the condensation module 10.

[0056] The optical module 20 includes a second sensor 21 and a third sensor 22. The second sensor 21 is used to detect temperature, which represents the temperature of the optical module 20, and the third sensor 22 is used to detect humidity, which represents the humidity of the optical module 20.

[0057] The motor module 30 includes a fourth sensor 31 for detecting temperature, which represents the temperature of the motor module 30.

[0058] The beneficial effect of this anti-condensation system for optical devices is that it activates the condensation module when a condensation risk is detected, causing oil or water to condense on the module and thus preventing condensation on the optical module, preventing fogging from affecting optical performance. Specifically:

[0059] ① When the temperature of the motor module exceeds the upper limit, the oil in the motor evaporates rapidly, which can easily condense on the optical module, affecting optical performance. If the condensation module is activated, the evaporated oil can condense on the condensation module instead of on the optical module;

[0060] ② When the optical module is close to its dew point, water is easily condensed on it. Therefore, the dew point is calculated based on the temperature and humidity of the optical module, and then the lower limit temperature value is calculated. That is, the lower limit temperature value calculated based on the temperature and humidity of the optical module is a temperature value related to the dew point temperature. When the temperature of the condensing module is lower than the lower limit temperature value, it means that the temperature of the optical module is also very low, possibly below the dew point temperature. If the condensing module is activated, water can be condensed on the condensing module instead of the optical module, and the humidity will be reduced, making it difficult for water to condense on the optical module.

[0061] In step ②, the dew point can be calculated according to the following steps:

[0062] Based on the temperature T1 of the optical module obtained from the second sensor and the humidity H1 of the optical module obtained from the third sensor, substitute into the following formula,

[0063]

[0064] A dew point temperature Td can be obtained, and a lower limit temperature value can be derived from this dew point temperature. The lower limit temperature value is higher than the dew point temperature; for example, the lower limit temperature is obtained by adding 2°C to the dew point temperature. When the temperature of the condensation module detected by the first sensor is lower than the lower limit temperature value, it indicates that the distance to the dew point is close, the risk of condensation is high, and the condensation module needs to be activated to absorb the water.

[0065] For example, given the formula above: T1 is 20℃, H1 is 50%, then...

[0066] Td = 20 - (100 - 50) / 5 = 10℃. Td + 2 = 12℃, meaning that when the temperature of the condensation module detected by the first sensor is below 12℃, it indicates that it is close to the dew point.

[0067] In summary, based on points ① and ② above, there are two situations or conditions that pose a risk of condensation:

[0068] ① The motor module temperature is high;

[0069] ② The optical module is close to the dew point, causing condensation.

[0070] Correspondingly, there are two situations or conditions under which the risk of condensation decreases:

[0071] ① The temperature of the motor module decreased;

[0072] ② The optical module is far from the dew point, where the temperature rises or the humidity decreases.

[0073] Therefore, after the condensing module 10 is started, conditions for stopping or slowing down the condensing module 10 can also be set, specifically:

[0074] ①When the temperature of the motor module 30 is higher than the upper limit temperature value and the condenser module 10 is started, and the temperature of the motor module 30 drops to the first normal temperature value, the condenser module 10 is controlled to stop.

[0075] ② When the temperature of the condensing module 10 is lower than the lower limit temperature value, or when the condensing module 10 is started and the slowdown or stop conditions are met, the condensing speed of the condensing module 10 is controlled to slow down or stop.

[0076] The temperature control module 40 detects whether the slowdown or stop conditions are met. The slowdown or stop conditions can be one or more of the following:

[0077] ①The humidity of the optical module 20 drops to a preset humidity threshold;

[0078] ② The dew point calculated based on the temperature and humidity of the optical module 20 decreases relative to the current temperature of the optical module 20, for example, until the difference from the current temperature reaches a preset temperature difference;

[0079] ③The condensation module 10 runs continuously for a preset time threshold.

[0080] To save space occupied by the condenser module 10, such as Figure 2 The condenser module 10 can be composed of a thermoelectric cooler 12 (Thermo Electric Cooler, TEC) and a condenser plate 13.

[0081] The advantages of using a semiconductor cooling chip in this embodiment are that it has no sliding parts or other complex moving mechanisms, occupies little space, significantly controls the space required, and can be flexibly arranged and is easy to implement. Furthermore, it requires no refrigerant, thus eliminating refrigerant pollution and ensuring high reliability.

[0082] In principle, a thermoelectric cooler utilizes the Peltier effect of semiconductor materials. When direct current passes through a thermocouple made of two different semiconductor materials connected in series, heat is absorbed and released at the two ends of the thermocouple, respectively, thus achieving the purpose of cooling. Therefore, a condenser plate can be positioned to contact the heat-absorbing end of the thermoelectric cooler. When current flows through it, heat is transferred from the condenser plate to the thermoelectric cooler, causing the temperature of the condenser plate to drop.

[0083] The temperature control module 40 controls the condenser module 10 to start, which means the temperature control module 40 controls the thermoelectric cooler 12 to start. Simply activating the thermoelectric cooler 12 will cause the temperature of the condenser plate 13 to drop, causing oil or water to condense on the condenser plate 13.

[0084] To allow for flexible adjustment of the condenser module 10, different methods can be used for control:

[0085] ① Set up multiple thermoelectric coolers. When the conditions for starting the condenser module are met, control all thermoelectric coolers to start, that is, all thermoelectric coolers have current. Then further reduce the number of thermoelectric coolers with current, that is, turn off some thermoelectric coolers, so that the remaining thermoelectric coolers have current.

[0086] ② Multiple thermoelectric coolers are installed. When the first condition for starting the condensation module is met, a smaller number of thermoelectric coolers are activated. When the second condition for starting the condensation module is met, a larger number of thermoelectric coolers are activated. When conditions improve and the risk of condensation decreases, some of the thermoelectric coolers are turned off.

[0087] ③ Multiple thermoelectric coolers are used. When the conditions for starting the condenser module are met for the first time, the first thermoelectric cooler is activated, allowing it to function. When the conditions for shutting down the condenser module are met for the first time, and the first thermoelectric cooler is shut down, the second thermoelectric cooler is activated when the conditions for starting the condenser module are met again, instead of the most recently used first thermoelectric cooler. This alternating activation of different thermoelectric coolers allows for sufficient heat dissipation, returning the thermoelectric coolers to their optimal operating state.

[0088] ④ Set up a pulse width control method. When the conditions for starting the condensation module are met, the control current continues to flow through the semiconductor cooling chip, that is, the duty cycle of the drive is 100%. Subsequently, when the risk of condensation decreases, the control drive duty cycle is reduced, for example, reduced to 80%, 50%, etc.

[0089] The position of the thermoelectric cooler 12 can be arranged in a variety of ways:

[0090] ① For lidar, if the optical module 20 and motor module 30 in the lidar are designed to be compact, the optical module 20 and motor module 30 can be regarded as a whole, and the semiconductor cooling chip 12 can be arranged on one side of the whole.

[0091] ② To better prevent the oil in the motor from evaporating and condensing onto the optical module 20, such as... Figure 3 Alternatively, the heat-absorbing end of a semiconductor cooling chip 12 and the condenser plate 13 can be arranged near the motor, and the heat-releasing end of the semiconductor cooling chip 12 can be arranged near the optical module 20. In this way, the heat is conducted to the optical module 20, making the optical module 20 less prone to condensation.

[0092] ③ Different semiconductor cooling chips can be set on different sides in the non-optical path direction to achieve a stronger effect or to use different cooling chips in turn.

[0093] Based on the above embodiments, this application also provides an optical device anti-condensation method applied to a temperature control module in the above-mentioned optical device anti-condensation system. The operation of the temperature control module includes at least one of the following:

[0094] The temperature of the motor module is obtained, and when the temperature of the motor module is higher than the upper limit temperature value, the condenser module is controlled to start.

[0095] The temperature and humidity of the optical module are obtained. Based on the temperature and humidity of the optical module, a lower limit temperature value is calculated. When the temperature of the condensing module is lower than the lower limit temperature value, the condensing module is controlled to start.

[0096] The optional implementation methods for the anti-condensation method of optical devices are the same as the optional implementation methods of the anti-condensation system of optical devices described above, and the corresponding beneficial effects are the same.

[0097] This application also provides a computer-readable storage medium storing a computer program or instructions, which, when executed by a computing device, implements the above-described method for preventing condensation in optical devices.

[0098] This application embodiment also provides a controller or temperature control module, which includes a memory and a processor. The memory is electrically connected to the processor, and the memory stores an executable program. When the processor executes the executable program, it implements the above-described method for preventing condensation in optical devices.

[0099] This application also provides a lidar, such as... Figure 4 The lidar includes the aforementioned optical device anti-condensation system. The lidar also has an original circuit board group 50. The temperature control module 40 can be set separately from the circuit board group 50 or integrated into the circuit board group 50.

[0100] In summary, this application proposes a method, system, and lidar for preventing condensation on optical devices. The method can be implemented by a temperature control module, which includes at least one of the following: controlling the activation of a condensation module when the temperature of the motor module exceeds an upper limit temperature value; calculating a lower limit temperature value based on the temperature and humidity of the optical module, and controlling the activation of the condensation module when its temperature falls below the lower limit temperature value. Activating the condensation module when a condensation risk is identified allows oil or water to condense on the module, thereby preventing condensation on the optical module and avoiding the impact of fogging on optical performance.

[0101] The apparatus and system embodiments described above are merely illustrative. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement these embodiments without any creative effort.

[0102] The above are merely preferred embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An anti-condensation system for optical devices, characterized in that, It includes a motor module, an optical module, a temperature control module, and a condenser module; the temperature control module is electrically connected to the motor module, the optical module, and the condenser module respectively. The temperature control module has at least one of the following functions: controlling the condenser module to start when the temperature of the motor module is higher than the upper limit temperature value; calculating the lower limit temperature value based on the temperature and humidity of the optical module, and controlling the condenser module to start when the temperature of the condenser module is lower than the lower limit temperature value; The condensation module includes a semiconductor cooling chip and a condenser plate; when the temperature control module is used to control the condensation module to start, the temperature control module is used to control the semiconductor cooling chip to start, reduce the temperature of the condenser plate, and cause oil or water to condense on the condenser plate.

2. The anti-condensation system for optical devices as described in claim 1, characterized in that, The temperature control module is used to control the condenser module to stop when the temperature of the motor module is higher than the upper limit temperature value, and when the temperature of the motor module drops to the first normal temperature value after the condenser module is started.

3. The anti-condensation system for optical devices as described in claim 1, characterized in that, The temperature control module is used to control the condensation rate of the condensation module to slow down or stop when the temperature of the condensation module is lower than the lower limit temperature value, or when the condensation module is started and the slowdown or stop conditions are met.

4. The anti-condensation system for optical devices as described in claim 3, characterized in that, The condensation module also includes a condenser plate and at least one semiconductor refrigeration chip; The steps of the temperature control module to control the condensation speed of the condensation module to slow down include: controlling the duty cycle of the drive signal of the thermoelectric cooler to decrease, or reducing the number of thermoelectric coolers in operation.

5. A method for preventing condensation on optical devices, characterized in that, A temperature control module applied to the anti-condensation system for optical devices according to any one of claims 1-4, wherein the operation of the temperature control module includes at least one of the following: The temperature of the motor module is obtained, and when the temperature of the motor module is higher than the upper limit temperature value, the condenser module is controlled to start. The temperature and humidity of the optical module are obtained. Based on the temperature and humidity of the optical module, a lower limit temperature value is calculated. When the temperature of the condensing module is lower than the lower limit temperature value, the condensing module is controlled to start. The condensation module further includes a semiconductor cooling chip and a condenser plate; the step of controlling the condensation module to start includes: controlling the semiconductor cooling chip to start, reducing the temperature of the condenser plate, so that oil or water condenses on the condenser plate.

6. The method for preventing condensation on optical devices as described in claim 5, characterized in that, The method for preventing condensation in optical devices also includes: When the temperature of the motor module is higher than the upper limit temperature value and the condenser module is started, and the temperature of the motor module drops to the first normal temperature value, the condenser module is controlled to stop.

7. The method for preventing condensation on optical devices as described in claim 5, characterized in that, The method for preventing condensation in optical devices also includes: When the temperature of the condensing module is lower than the lower limit temperature value, and the condensing module is started, and the slowdown or stop conditions are met, the condensing rate of the condensing module is controlled to slow down or stop.

8. A lidar, characterized in that, The optical device anti-condensation system includes any one of claims 1-4.

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