To consider the environment during ground vehicle driving, the inertially stabilized platform (ISP) can be used for electro-optical tracking instruments to isolate the senor's line of sight (LOS) from the carrier's vibrations with high precision and stability. This paper proposes the combination of a backstepping sliding mode controller with the adaptive neural networks approach (BSMC-NN) for ISP that achieves output torque saturation and considers parametric uncertainties, friction, and gimbal mass imbalance. An adaptive radial basis function neural network is adopted to approximate uncertain disturbances in this dynamic system. In contrast to the existing saturated control structures, an auxiliary function is designed to compensate for any error between the designed and the actual control torque. The closed-loop stability and asymptotic convergence performance are guaranteed based on the Lyapunov stability theory. Finally, the simulation and experimental results demonstrate that this proposed controller can effectively regulate the gimbal rotation angle under different external disturbances. This offers superior control performance despite the existence of the nonlinear dynamics and control input constraints.

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The contact between two rough surfaces is essentially the contact between micro-bulge of different shapes. In the process of interference fit, the distribution of contact area and contact stress at different positions of the two rough contact surfaces is uneven. In this paper, based on the test results of the morphology of machined surfaces with different surface roughness, a two-dimensional curve model of the contact surface is established according to the W-M fractal function and Matlab software. The contact area and contact load are analyzed with a two-dimensional finite element contact model of the double rough surface that established with Abaqus software. And the effect of surface roughness and surface displacement on the contact area and contact load is analyzed with the finite element contact model.

The present study proposed a novel projection display system based on a virtual reality enhancement environment. The proposed system displays stereoscopic images of fractures and enhances the computed tomography (CT) images. The diagnosis and treatment of fractures primarily depend on the post-processing of CT images. However, two-dimensional (2D) images do not show overlapping structures in fractures since they are displayed without visual depth and these structures are too small to be simultaneously observed by a group of clinicians. Stereoscopic displays may solve this problem and allow clinicians to obtain more information from CT images. Hardware with which to generate stereoscopic images was designed. This system utilized the conventional equipment found in meeting rooms. The off-axis algorithm was adopted to convert the CT images into stereo image pairs, which were used as the input for a stereo generator. The final stereoscopic images were displayed using a projection system. Several CT fracture images were imported into the system for comparison with traditional 2D CT images. The results showed that the proposed system aids clinicians in group discussions by producing large stereoscopic images. The results demonstrated that the enhanced stereoscopic CT images generated by the system appear clearer and smoother, such that the sizes, displacement and shapes of bone fragments are easier to assess. Certain fractures that were previously not visible on 2D CT images due to vision overlap became vividly evident in the stereo images. The proposed projection display system efficiently, economically and accurately displayed three-dimensional (3D) CT images. The system may help clinicians improve the diagnosis and treatment of fractures.

Using B 13 vibrating mode and fixing inner side of stator, a new disc-type of traveling wave ultrasonic motor (TWUSM) was designed. Finite element method was introduced to simulate the vibrating mode of stator, considering structure factors like outer diameter of stator, numbers and height of stator teeth. The variation curves of related vibration parameters were calculated, such as amplitude of stator teeth, resonant frequency, vibrating speed elliptical locus of particles in contact surface and so on. Furthermore, a prototype of 40 disc-type of TWUSM was fabricated. And the driving characteristics were investigated. The results showed that this kind of TWUSM had a simple structure, light weight, high rotational speed, and a certain torque as well.