A method for determining the parameters of the damping link to isolate harmful temperature feedback

Abstract

The present invention relates to a method for determining damping link parameters for isolating harmful temperature feedback, comprising the following steps: Step 1: obtaining the enclosed air temperature T1 surrounding the inertial platform and the ambient temperature T2 surrounding the inertial platform frame; Step 2: rotating the inertial platform to obtain the maximum change dT2 of the ambient temperature T2 surrounding the inertial platform frame; Step 3: determining a damping target based on the temperature sensitivity of the inertial element and the accuracy of the inertial navigation system; Step 4: determining a target time t based on actual rotation conditions; Step 5: calculating the damping link time constant T based on the first-order system response curve c(t) = 1-e(-t / T), thereby determining the transfer function of the damping link. The present invention can fundamentally solve the problem of harmful temperature disturbances and improve the accuracy of temperature control.

Description

Technical Field

[0001] The present invention belongs to the technical field of inertial navigation systems and relates to a method for determining damping link parameters, in particular to a method for determining damping link parameters for isolating harmful temperature feedback. Background Art

[0002] In inertial navigation systems, the inertial measurement element (IME) mounted on the inertial platform is a heat-generating device. The function of the inertial platform temperature control is to maintain a stable internal temperature field by controlling the temperature of the air surrounding the inertial platform. In high-precision inertial navigation equipment, the IME mounted on the inertial platform is very sensitive to changes in the temperature field of the space in which it is located. Therefore, multi-stage temperature control is often used to resolve the conflict between high precision and high environmental adaptability.

[0003] Due to the presence of lateral temperature gradients in the ambient temperature field, the rotational state ultimately causes temperature fluctuations around the inertial measurement element. This temperature, which affects temperature control accuracy, enters the temperature control feedback network and is referred to in this article as "detrimental temperature feedback." To address the impact of detrimental temperature and achieve temperature uniformity within the inertial platform, a common approach is to increase the number of temperature sensors and employ smoothing to reduce their impact. However, this approach increases the burden on hardware and wiring, has limited effectiveness, and does not fundamentally resolve the problem. Another approach is to increase the number of temperature control stages, gradually reducing the detrimental temperature, ultimately achieving temperature stability within the inertial platform. However, this approach has the disadvantages of high cost and high power consumption.

[0004] Therefore, the present invention proposes a method for determining the parameters of a damping link for isolating harmful temperature feedback, which can overcome the above problems.

[0005] After searching, no prior art documents identical or similar to the present invention were found. Summary of the Invention

[0006] The purpose of the present invention is to overcome the shortcomings of the existing technology and propose a method for determining the parameters of a damping link for isolating harmful temperature feedback. By designing a damping link, harmful temperature is blocked from entering the temperature feedback channel at the source, fundamentally solving the problem of harmful temperature disturbance and improving the accuracy of temperature control.

[0007] The present invention solves the practical problem by adopting the following technical solutions:

[0008] A method for determining damping link parameters for isolating harmful temperature feedback comprises the following steps:

[0009] Step 1: Obtain the enclosed air temperature T1 around the inertial platform and the ambient temperature T2 around the inertial platform frame;

[0010] Step 2: Rotate the inertial platform to obtain the maximum change dT2 of the ambient temperature T2 around the inertial platform frame;

[0011] Step 3: Determine the damping target based on the temperature sensitivity of the inertial element and the accuracy of the inertial navigation system;

[0012] Step 4: Determine the target time t according to the actual rotation conditions;

[0013] Step 5: According to the first-order system response curve c(t)=1-e(-t / T), the time constant T of the damping link is calculated, thereby determining the transfer function of the damping link.

[0014] Moreover, before isolating the harmful temperature feedback, the temperature value of the enclosed air around the inertial platform in step 1 is T1≈40°C and the ambient temperature around the inertial platform frame is T2≈35°C;

[0015] Moreover, the maximum change in the ambient temperature T2 of the inertial platform frame in step 2 is dT2 = 2°C;

[0016] Moreover, the specific method of step 3 is:

[0017] Determine the damping target based on the temperature sensitivity of the inertial element and the accuracy of the inertial navigation system

[0018] (1-F)*(1 / dT2)*dT0;

[0019] dT0 is the temperature control target fluctuation value.

[0020] Moreover, the transfer function of the damping link in step 5 is Gn=K / (Ts+1), and the calculated time constant of the damping link is T=676s;

[0021] Moreover, the step 5 further includes the following steps:

[0022] Step 6: Design the damper and install it on the inertial platform frame.

[0023] Advantages and beneficial effects of the present invention:

[0024] 1. The present invention blocks the influence of harmful temperature from the source and improves the temperature uniformity inside the inertial platform.

[0025] 2. The present invention improves the temperature control effect without increasing the number of temperature sensors, reducing the hardware and wiring burden of the inertial navigation system

[0026] 3. The present invention does not increase the temperature control stages of the inertial navigation system and has the characteristics of low cost and low power consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1It is the electrical principle diagram and main signal distribution diagram of the present invention. DETAILED DESCRIPTION

[0028] The following further describes the embodiments of the present invention:

[0029] A method for determining damping link parameters for isolating harmful temperature feedback comprises the following steps:

[0030] Step 1: Obtain the enclosed air temperature T1 around the inertial platform and the ambient temperature T2 around the inertial platform frame;

[0031] In this embodiment, before isolating the harmful temperature feedback, the temperature value of the enclosed air around the inertial platform in step 2 is T1≈40° C. and the ambient temperature around the inertial platform frame is T2≈35° C.;

[0032] Step 2: Rotate the inertial platform to obtain the maximum change dT2 of the ambient temperature T2 around the inertial platform frame;

[0033] In this embodiment, the maximum change in the ambient temperature T2 of the inertial platform frame in step 2 is dT2 = 2°C;

[0034] Step 3: Determine the damping target based on the temperature sensitivity of the inertial element and the accuracy of the inertial navigation system;

[0035] The specific method of step 3 is:

[0036] Determine the damping target (1-F)*(1 / dT2)*dT0 based on the temperature sensitivity of the inertial element and the accuracy of the inertial navigation system;

[0037] dT0 is the temperature control target fluctuation value.

[0038] In this embodiment, the target value F is set to 0.15 and dT0 is set to 0.2°C;

[0039] Step 4: Determine the target time t according to the actual rotation conditions;

[0040] In this embodiment, the target time t of step 4 is 60s;

[0041] Step 5: According to the first-order system response curve c(t)=1-e(-t / T), the damping link time constant T is calculated to determine the transfer function of the damping link;

[0042] In this embodiment, the block diagram of the temperature control system is as follows: Figure 1 As shown in the figure, Gc is the open-loop transfer function of PID control, and Gn uses the inertia link as the damping link;

[0043] In step 5, the transfer function of the damping link is Gn=K / (Ts+1), and the time constant of the damping link is calculated to be T=676s;

[0044] In this embodiment, K = 0.6;

[0045] Step 6: Design the damper and install it on the inertial platform frame.

[0046] The specific method of step 6 is:

[0047] In this embodiment, the designed damper is installed on the inertial platform frame.

[0048] In this embodiment, T2 = (35 ± 1.0) ° C., T1 = (40 ± 0.6) ° C. before isolation, and T2 = (35 ± 1) ° C., T1 = (40 ± 0.1) ° C. after isolation.

[0049] It should be emphasized that the embodiments described in the present invention are illustrative rather than restrictive. Therefore, the present invention includes but is not limited to the embodiments described in the specific embodiments. Any other embodiments derived by those skilled in the art based on the technical solutions of the present invention also fall within the scope of protection of the present invention.

Claims

1. A method for determining the parameters of a damping element for isolating harmful temperature feedback, characterized in that: The following steps are involved: Step 1: Obtain the enclosed air temperature T1 around the inertial platform and the ambient temperature T2 around the inertial platform frame; Step 2: Rotate the inertial platform to obtain the maximum change dT2 of the ambient temperature T2 around the inertial platform frame; Step 3: Determine the damping target based on the temperature sensitivity of the inertial element and the accuracy of the inertial navigation system; Step 4: Determine the target time t according to the actual rotation conditions; Step 5: According to the first-order system response curve c(t)=1-e(-t / T), the time constant T of the damping link is calculated, thereby determining the transfer function of the damping link.

2. The method for determining the damping link parameters for isolating harmful temperature feedback according to claim 1, characterized in that: Before isolating the harmful temperature feedback, the temperature of the enclosed air around the inertial platform in step 1 is T1≈40°C and the ambient temperature around the inertial platform frame is T2≈35°C.

3. The method for determining the parameters of a damping element for isolating harmful temperature feedback according to claim 1, characterized in that: The maximum change dT2 of the ambient temperature T2 of the inertial platform frame in step 2 is 2°C.

4. The method for determining damping link parameters for isolating harmful temperature feedback according to claim 1, characterized in that: The specific method of step 3 is: Determine the damping target based on the temperature sensitivity of the inertial element and the accuracy of the inertial navigation system (1-F)*(1 / dT2)*dT0; dT0 is the temperature control target fluctuation value.

5. The method for determining the damping link parameters for isolating harmful temperature feedback according to claim 1, characterized in that: In step 5, the transfer function of the damping link is Gn=K / (Ts+1), and the time constant of the damping link is calculated to be T=676s.

6. The method for determining the parameters of a damping element for isolating harmful temperature feedback according to claim 1, characterized in that: The step 5 further includes the following steps: Step 6: Design the damper and install it on the inertial platform frame.

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