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To improve the calibration accuracy of the gyroscope error model coefficients, a multi-position calibration method based on a two-axis turntable is proposed. By incorporating the turntable errors and the gyroscope installation errors into the calibration model, a multi-position gyroscope input-output model is established in the gravity field. The gyroscope static error model coefficients are calibrated by the least square method. Compared to the 8-position calibration method, the calibration method proposed in this paper can automatically avoid two-axis turntable errors and eliminate the influence of difficult-to-measure gyroscope installation errors on calibration results, thereby improving the calibration accuracy of the gyroscope. Error analysis verifies the effectiveness of the calibration method proposed.

To meet the demands of high mobility and rapid deployment in modern warfare, conventional multi-vehicle mobile radars have shown increasing limitations in integration and mobility. This paper focuses on a single-vehicle mobile radar with high integration by introducing an adaptive locking technology for high-rigidity turntable transportation. Combined with mechanical simulation, this approach ensures the safety and reliability of the turntable during road transportation. Furthermore, ergonomics simulation tailored for single-vehicle with high integration design is employed to optimize maintenance pathways within the limited space, enhancing the efficiency of device maintenance. Finally, to meet the low-envelope size requirements for railway transport, ADAMS kinematic simulation technology based on multi-load is applied to perform kinematic analysis of the radar antenna’s lifting and stowing processes. This method enables rapid transitions between transport and operational states. Valuable insights are provided for the structural design of similar single-vehicle mobile radar with high integration.

Effective vibration isolation is critical for minimizing the transmission of unwanted mechanical energy from a source to its surrounding environment, especially in precision systems, where even minor disturbances can degrade performance. This study addresses the challenge of low-frequency vibration transmission in lightweight, high-sensitivity audio devices such as turntables with masses below 10 kg. Traditional vibration mitigation strategies—primarily based on increasing system mass to raise the resonant frequency—are unsuitable for such systems due to weight constraints and potential impacts on operational dynamics. Previous studies have identified a critical resonance range of 5–15 Hz, corresponding to the tonearm and cartridge assembly, where transmitted vibrations can compromise signal fidelity and cause mechanical degradation. This research aims to develop an effective and universal vibration isolation solution tailored for lightweight turntables, focusing on external isolation from structural vibration sources such as furniture and flooring. To achieve this, a two-stage experimental methodology was employed. In the first stage, the excitation method with the use of a hammer tapping machine was evaluated for its ability to simulate real-world vibrational disturbances. The most representative excitation methods were then used in the second stage, where the isolation performance of various materials and systems was systematically assessed. Tested isolation strategies included steel springs, elastomeric dampers, and commercial linear vibration isolators. The effectiveness of each isolation material was quantified through spectral analysis and transfer function modeling of vibration acceleration data. The results provide comparative insights into material performance and offer design guidance for the development of compact, high-efficiency anti-vibration platforms for audio turntables and similar precision devices.

In this paper, the structural types of autonomous reconnaissance photoelectric turntables and the electrical system design methods of autonomous reconnaissance control are proposed and simplified. Meantime, the key technologies of autonomous reconnaissance photoelectric turntables are proposed and simplified, and the human-computer interaction interface of the autonomous reconnaissance photoelectric turntable is described, the concept of autonomous collaboration and its corresponding collaborative algorithms is explained, and the prospects for future development direction are proposed.

Quantum key distribution (QKD) provides the only intrinsically unconditional secure method for communication based on the principle of quantum mechanics. Compared with fibre-based demonstrations, free-space links could provide the most appealing solution for communication over much larger distances. Despite significant efforts, all realizations to date rely on stationary sites. Experimental verifications are therefore extremely crucial for applications to a typical low Earth orbit satellite. To achieve direct and full-scale verifications of our set-up, we have carried out three independent experiments with a decoy-state QKD system, and overcome all conditions. The system is operated on a moving platform (using a turntable), on a floating platform (using a hot-air balloon), and with a high-loss channel to demonstrate performances under conditions of rapid motion, attitude change, vibration, random movement of satellites, and a high-loss regime. The experiments address wide ranges of all leading parameters relevant to low Earth orbit satellites. Our results pave the way towards ground–satellite QKD and a global quantum communication network. Full-scale verifications for establishing quantum cryptography communication via satellites are reported. Three independent experiments using a hot-air balloon are performed: on a rapidly moving platform over a distance of 40 km, on a floating platform over a distance of 20 km, and over 96 km in air with a huge loss.

In order to solve the problems such as the limited field of view of traditional self-collimation detection, the inability to achieve continuous detection of 0~360° full circumference and the existence of zero drift in self-collimation measurement. The positive and negative rotation of the inner and outer axes of the dual-axis turntable is used to realize high-precision continuous angle measurement with the autocollimator as the angle reference, and the combination of the compensation target and the fixed target is used to realize the closed-loop compensation of the drift of the autocollimator. The results show that: the repeatability error of the system is 0.05”, and the detection accuracy of the system reaches 1.64”. On the premise of ensuring the stability of the self-collimation angle reference, the self-collimation full-scale small angle measurement is realized.

Aiming at the nonlinear links in the mechanical transmission structure design of the servo system of a large planar mirror turntable and the characteristic that parameters are difficult to identify, this paper designs an active disturbance rejection controller based on an improved nonlinear function to achieve the position servo control of the turntable. Firstly, the physical model of the turntable is built by using the MATLAB/Simulink Simscape-Multibody toolbox, and the mathematical model of the rotating motor is simplified to obtain the overall simulation model of the controlled object. Secondly, a second-order active disturbance rejection controller is designed. On this basis, a scheme for improving the nonlinear function is proposed and its convergence is proved. Finally, simulation experiments are completed on the MATLAB/Simulink platform. The experimental results show that the improved ADRC controller has higher tracking accuracy, faster dynamic response speed, and better anti-interference ability.

In response to the requirement for traction sliding mode in a follow-up steering function, a follow-up steering system with static pressure support is built, using the traction conditions of the B737-800 as a case study. To achieve optimal working conditions in the new traction taxiing mode, simulations of the fluid domain and analyses of bearing characteristics are conducted, revealing the impact of system parameters on the distribution of the pressure and velocity fields of the turntable under standard operating conditions. The precise impacts of parameters like oil supply pressure and orifice diameter on the oil film-bearing performance of vertical and radial turntables are investigated in greater detail. By analyzing the distribution of oil film pressure and velocity under varying conditions, the influence of these parameters on total bearing capacity is ascertained. The performance offers a theoretical foundation and direction for the design and optimization of hydrostatic turntables, presenting significant practical value.

To address issues such as frequent failures and high maintenance complexity in large overload static pressure turntables, this paper establishes a subsystem fault tree model for large overload static pressure turntables. It combines fuzzy mathematics theory to conduct a fault tree analysis, utilizing triangular fuzzy numbers to describe the failure probability of the turntable subsystem. This approach identifies the weak links that impact the reliability of the turntable system and devises reliability optimization solutions.

Based on ANSYS finite element analysis software, a method of extracting stiffness matrix of four-point contact ball bearing was proposed. The finite element model of four-point contact ball bearing was established, the stress and strain of the bearing under different loads were calculated, and the relationship between load and stress and strain was analyzed, The global stiffness matrices of turntable bearing with steel and aluminum as inner ring materials are extracted and compared, and the causes of large changes in the matrix are analyzed.