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The boost-glide rocket needs to maneuver in the atmosphere with complex flight conditions, which is a big challenge for the attitude control system. In this paper, the design process of the control system is analyzed. With specific points of the flight trajectory, the design of an improved proportional-integrative-derivative (PID) controller based on the small perturbation theory is carried out. Design approach of the attitude control system is verified by the six-degree-freedom model simulation. The rocket flight control program is written to the onboard computer so that hardware-in-the-loop simulation experiment is completed. Experimental results show that the mean and standard deviation of the error between simulation value and experiment value are below 0.5°, so the control parameters and design method are reasonable with a great attitude tracking effect. This paper proposes the design and verification method of a boost-glide rocket attitude control system, which can provide a reference for design of the boost-glide rocket around the world.

For aircraft which move in the atmosphere, the angle of attack and angle of sideslip cannot be measured precisely. This limits the precision of guidance and control systems, so the flush air data sensing system module with navigation and temperature information is designed for atmosphere parameter calculation. In this work the traditional parameter calculation method is improved, and a new algorithm which combines pressure data, temperature data and navigation data to calculate the atmosphere parameters is proposed. A ground experiment test scheme with a simulated flight environment is designed and the measured data is fitted and filtered to complete the experiments. The flush air data sensing module gets pressure data and temperature data of the atmosphere with sensors, and the measured data is integrated with navigation information to calculate the aircraft parameters of the angle of attack, angle of sideslip, dynamic pressure, static pressure, Mach number and so on. Calculated parameters can be transmitted to guidance and control systems to improve the attitude and trajectory precision for an aircraft. Experimental results show that the software and hardware of the flush air data system module with navigation and temperature information work well, and communication of various devices is normal. The flight status of aircraft can be precisely calculated online, which provides a useful reference for prospective wind tunnel experiments and flight tests.

Legged robots have better performance on discontinuous terrain than that of wheeled robots. However, the dynamic trotting and balance control of a quadruped robot is still a challenging problem, especially when the robot has multi-joint legs. This paper presents a three-dimensional model of a quadruped robot which has 6 Degrees of Freedom (DOF) on torso and 5 DOF on each leg. On the basis of the Spring-Loaded Inverted Pendulum (SLIP) model, body control algorithm is discussed in the first place to figure out how legs work in 3D trotting. Then, motivated by the principle of joint function separation and introducing certain biological characteristics, two joint coordination approaches are developed to produce the trot and provide balance. The robot reaches the highest speed of 2.0 m·s−1, and keeps balance under 250 Kg·m·s−1 lateral disturbance in the simulations. The effectiveness of these approaches is also verified on a prototype robot which runs to 0.83 m·s−1 on the treadmill. The simulations and experiments show that legged robots have good biological properties, such as the ground reaction force, and spring-like leg behavior.

In order to implement the real-time filtering and tracking of robot signals with high efficiency, a novel real-time filtering method based on neuron filtering mechanism is developed in this paper. By considering the ubiquity of resonance in mammal and combining the mechanism of neural information processing, the derived details and the feasible parameter criterion under minimum error variance condition are given. For illustration, the application on quadruped robot is discussed. The quadruped robot feet speed signals are processed by developed real-time filtering method and Kalman filtering algorithm, respectively, and the computation time of both methods is tested. Experiment results show that the performance of developed real-time filtering method is better than that of Kalman filtering algorithm, not only in filtering and tracking performance but also in filtering speed. The novel real-time filtering method based on neuron filtering mechanism can effectively implement the real-time filtering and tracking with regard to robot signals.

In order to avoid tangential and axial tensile stress, both the temperature and the stress distribution of the ceramic-steel cavity die in cold extruding is analyzed with the static structure analysis by the finite element method. Taking the two-layer cavity die as an example, it indicates that the tensile stress only affects the middle region of the die during the extrusion process, and the biggest tensile stress is concentrated on the middle region, the value in the top and the base is relatively small. And along with enhancement of the friction coefficient, the plastic deformation resistance of metallic material is got bigger and bigger, the lateral pressure and the tensile stress which the ceramic-steel cavity die received is also increased.

virtual experiment is an approach to utilize numerical computation to study the complex physics processes, and is used widely in the areas of weapon system development and performance evaluation. The virtual experiment for warhead aims at studying various conditions of damage on target by warhead, analyzing the factors of warhead power, and provide the basis for the warhead design, with high quality cluster systems and high precise FEA software. This paper is based on virtual experiment over the shaped-charge warhead, and study the virtual experiment design and analysis methods.

A CMOS UV and blue-extended photodiode is presented and fabricated for light detection in the ultraviolet/blue spectral range. An octagon homocentric ring-shaped geometry is used to improve the ultraviolet responsivity and suppress edge breakdown. This paper has established a two-dimensional responsivity physical model for the presented photodiode and given some numerical analyses. The dead layer effect, which is caused by the high-doping effects and boron redistribution, is considered when analyzing the distribution of the current of the proposed UV and blue-extended photodiode. In the dead layer, the boron doping profile decreases towards the surface. Simulated results illustrate that the responsivity in the UV range is obviously decreased by the effect of the dead layer, while it is not affected in the visible and near-infrared part of the spectrum. The presented photodiode is fabricated and the silicon tested results are given, which agree well with the simulated ones.

Amorphous/crystalline silicon heterostructure solar cells have been fabricated by hot wire chemical vapor deposition (HWCVD) on textured p-type substrates. The influence of chemical polish (CP) etching and the post annealing process on the solar cell performance have been studied. The CP treatment leads to a reduction of stress in the i-layer by the slight rounding of the pyramid peaks, therefore improving the deposition coverage and the contact by each layer, which is beneficial for the performance of the solar cells. An optimized etching time of 10–15 s has been obtained. A post annealing process leads to a considerably improved open voltage (Voc), filled factor (FF), and conversion efficiency (η) by restructuring the deposited film and reducing the series resistance. An efficiency of 15.14% is achieved that represents the highest result reported in China for an amorphous/crystalline heterostructure solar cells based on the textured p-type substrates.