With the development of the times, the objective requirement of CIM is to establish a 3D digital city. This article proposes a software front-end and back-end open source solution for the production and release of 3D modeling in different industries. This article is based on the construction practice of CIM basic platform database, and analyzes the spatial resolution and corresponding entity expression effect of 3D models in CIM basic platform from the perspective of CIM industry application, as well as the advantages and disadvantages of application. It also elaborates on the classification of 3D models and the geographic elements and buildings they contain, and introduces the relationship between 3D models and vector data, raster data, attribute data, as well as the difficulties of modeling technology. On this basis, large-scale 3D modeling and mapping experiments were conducted in the power industry, water industry, construction industry, and indoormap scene. The article has improved and optimized the algorithms for 3D excavation volume and wire azimuth, and introduced various parametric modeling techniques. From the perspective of project application and user feedback, the modeling quality, performance, and user experience have been recognized by the market. This article has certain reference value for the construction of the 3D model basic framework, theme oriented model system, modeling technology selection, and the release of massive 3D data services in the CIM basic platform construction.

Observer-based control is the most commonly used method in the control of electro-hydraulic servo system (EHSS) with uncertainties, but it suffers from the drawback of low accuracy under the influence of large external load forces and disturbances. To address this problem, this paper proposes a novel compensation function observer-based backstepping sliding mode control (BSMC) approach to achieve high-accuracy tracking control. In particular, the model uncertainties, including nonlinearities, parameter perturbations and external disturbances are analyzed and treated together as a lumped disturbance. Then, a fourth-order compensation function observer (CFO) is constructed, which fully utilizes the system state information to accurately estimate the lumped disturbance. On this basis, the estimate of the lumped disturbance is incorporated into the design of an backstepping sliding mode controller, allowing the control system to compensate for the disturbance effect. The stability of the closed-loop control system under the CFO and BSMC is rigorously proven through the use of Lyapunov theory, which guarantees that all the tracking error signals converge exponentially to the origin. Comparative simulations are carried out to show the effectiveness and efficiency of the proposed approach, i.e., compared with PID and ESO-based BSMC methods, the tracking accuracy is improved by 99.93% and 99.76%, respectively.