With the increasing demands of users for function, quality, cost, personalization and environmental friendliness of products, manufacturing companies must become more responsive to the changing market needs. As a new design paradigm, the adaptable design can meet the needs of users, manufacturing enterprises and society in the product life cycle through the comprehensive optimization of the design process, so as to improve economic and environmental benefits. To improve the adaptability of product design, it is critical to quantify and scientifically express the adaptability in order to establish its comprehensive evaluation index system in the process of design decision-making. Aiming at the quantitative evaluation of product adaptable design, the product adaptable design architecture was constructed and customer requirements were mapped to function domains, structure domains and parameter domains in sequence; based on the information entropy theory, a calculation method of information entropy for the product adaptable design evaluation was established, which could transform the subjective and qualitative adaptable product evaluation into quantitative descriptions through the variant degree, so as to realize the objective evaluation of the adaptability of individual products, product series and product platforms. The results of a design example of a cylindrical gear processing machine show that the proposed evaluation method can assist designers in evaluating and making decisions on product design schemes.

In order to improve positioning accuracy of parts in virtual maintenance training, enrich human-computer interaction functions, reflect the closer to actual operation processes, and improve training quality of operator, the assembly constraint perception and establishment algorithm was analyzed based on virtual reality aided technology. The correct assembly constraint could be established in real time according to the current assembly state. Based on intuitive interactions, the multi-mode guidance method of “tutor & teaching assistant” was established. The unmarked interaction operation modes of virtual hand and virtual tools were developed in Unity3D environment. The virtual environment stereoscopic visualization was realized by HMD （head-mounted display）. A virtual maintenance training system was developed and its test was performed taking a washing machine as the object. The results showed that this system could make the positioning of assembly relation of parts more accurate, simulate more realistic disassembly processes and help operator complete tasks better through intuitive interaction, which can eliminate shortage of actual training and greatly improve the maintenance training cost-effectiveness ratio.

In order to reduce the harmful vibration of power equipment and building floor, the passive and active dynamic vibration absorption (DVA) was systematically studied. Particle swarm optimization (PSO) algorithm was introduced to optimize the design of the parameters of passive DVA without damping and with damping in the main system, the weight matrices in linear quadratic regulator (LQR) active control and the parameters of k_p, k_i, k_d in proportion-integral-derivative (PID) active control. In the vibration control of building floor, based on the utilization of passive tuned mass damper (PTMD), an active tuned mass damper (ATMD) was designed for vibration control in ANSYS finite element environment. The results verified the feasibility and effectiveness of the proposed strategy, and provide a basis for the calculation and effect prediction for engineering structure vibration control. The research can further develop the advanced DVA technology for power equipment and building floor.

In the case that the technological datum does not coincide with the design datum, when the extremum method is used to calculate the technological dimension chain during the part processing, the false waste product with unqualified process dimension but probably qualified design dimension often occurs. For this reason, based on the characteristics of the calculation of technological dimension chain by the extremum method, the occurrence reason of the false waste product was analyzed. In order to facilitate the identification of the false waste product during the part processing, a new dimension chain was established and calculated by taking the process dimension as the closed link dimension, so the necessary and insufficient condition to indirectly guarantee qualified design dimension was obtained. Then, a novel calculation method and flow of the process dimension tolerance range for identifying the false waste product were proposed by incorporating the actual deviations of composition loop dimensions generated before the process dimension. In order to avoid the conversion of the false waste product into a real waste product with an unqualified design dimension, a remedial measure based on the tolerance compression of dimensions in the subsequent processing was proposed. According to the mutual compensation relationship among the dimensions of each composition loop in the technological dimension chain, the calculation method and flow of the limit deviation and the tolerance of the dimension after tolerance compression in the subsequent processing were analyzed. The research results can provide guidance for the identification and remedy of the false waste product.

Aiming at the design of the interference of hub bearing unit in the third-generation automotive, a theoretical design method of the interference considering the influence of riveting assembly is proposed. Firstly, the theoretical calculation formula for the interference of the fit between the inner ring and the inner flange shaft of the hub bearing unit was derived based on the elasticity and plane stress assumptions. Secondly, the finite element software was used to establish simulation models of the interference assembly process, the riveting assembly process and the riveting unloading springback process of the hub bearing unit, and the pressure distribution of the interference fit surface and the axial pre-stress of the hub bearing unit were obtained by the numerical simulation. Thirdly, the interference increased due to riveting assembly was calculated based on the derived theoretical formula, and the theoretical calculation value was corrected. Finally, the correctness and reliability of the proposed theoretical design method of interference were verified through the pull-out force test of the inner ring and the endurance test of the hub bearing unit. The results showed that the theoretical interference increased due to the riveting assembly was 0.020 mm, which was good agreement with its experimental value of 0.017 mm. Moreover, the hub bearing units with interference near the upper and lower limits had no inner ring looseness or inner ring rupture. Research shows that the theoretical design method of interference considering the influence of riveting assembly is reliable and can meet the requirements of production practice.

Avionics modular heat storage device is a type of thermal management device widely used in avionics. In order to provide theoretical support for the engineering design of avionics module heat storage device, the relationship between the operating time, power consumption and set temperature is studied. Firstiy, considering the effects of natural convection and heat radiation, a thermal model of heat storage device under the actual operating environment was developed by using the heat transfer theory. Then, the enthalpy-porous media method was applied to numerically simulate the transient heat storage process of the heat storage device, and the accuracy of the numerical simulation method was validated by solving the Stefan problem with the temperature field theoretical solution in the phase change heat transfer. Finally, the temperature rise curves of the heat storage device and the melting process curves of the phase change material were obtained under four typical kinds of power consumption, and compared with the ideal curves under the adiabatic condition of the top surface; at the same time, the dependent variable relationship between the operating time, power consumption and set temperature for the heat storage device was obtained based on the theoretical rules and the numerical simulation results, and a binary linear regression analysis on the dependent variable relationship was conducted by the least square method. The results showed that, compared with the adiabatic condition of the top surface, the temperature rise process of the heat storage device and the melting process of the phase change material under the low power consumption were significantly affected by the natural convection and thermal radiation; the operating time of the heat storage device had a linear relationship with the power consumption under the double logarithmic coordinate, and it had a linear relationship with the set temperature under the single logarithmic coordinate; the operating time prediction formula for the heat storage device constructed by the binary linear regression method had a good prediction effect. Its fitting error was within ±4% and the fit goodness was 0.993 in the modeling set, and the prediction error in the verification set was within ±3%. The operating time prediction formula for the heat storage device can be used as a tool for the agile engineering design of the avionics module heat storage device.

According to the control criterion of tensile and compressive stress of dam body in the current Design specification for stone masonry dam （SL25—2006）, the structural safety degree of some small stone masonry arch dams whose cementing materials have been aged and degraded is often unable to reach a conclusion conforming to the qualitative judgment. Therefore, new analysis and evaluation methods need to be developed. Based on the nonlinear multi-arch beam method, ADAO (arch dam analysis and optimization) software was used to simulate and analyze the dam body stress of Longtan masonry arch dam and Shimen masonry arch dam and the dam structural safety degree under the failure modes of tension, compression and shear. The result showed that it was difficult to evaluate the arch dam structural safety degree quantitatively because the dam body stress basically met the stress control standard of the design specification, when the current design specification of arch dam in China took the tensile and compressive stress as the main evaluation basis for judging the arch dam structural safety. After considering the shear failure mode of the dam body, the quantitative evaluation of the apparent lack of dam structural safety degree could be obtained. The research results provide a new idea for the analysis and evaluation of the structural safety degree of stone masonry arch dams. It is necessary to further study and put forward the structural shear safety control criteria of stone masonry arch dam, which can be used as an important supplement of arch dam structural safety degree evaluation criteria.

In order to improve the speed control accuracy and adaptability of mobile robots under the complex environment, a speed control method of the mobile robot based on the multi-sensor fusion information is proposed. Firstly, according to the multi-sensor nonlinear optimization fusion theory, an optimized estimation model of mobile robot motion states was constructed by minimizing the residual errors of the motion observation. Then, the observation methods of the mobile robot motion by the monocular camera, the wheel odometer and the inertial measurement unit (IMU) were introduced, and the residual errors and their Jacobian matrices of the mobile robot motion observed by different sensors were calculated. Finally, the speed control system of the mobile robot was designed by combining the estimated motion state information with the incremental PID (proportion integration differentiation) control strategy, and the performance of this control system was verified through a number of tests. The test results showed that the proposed speed control method of the mobile robot effectively reduced the speed estimation error, and had a greater improvement in accuracy and robustness than the speed control method based on the wheel odometer information. The research result has significant significance for improving the performance of mobile robots in complex environments.

Dynamic mechanical automatic vertical drilling tool is widely used in vertical well operations. Improving its restoring performance is the key goal of optimizing drilling tool. The opening angle of upper disc valve in the stable platform has a great influence on the restoring performance. In view of this, three indexes of expansion force impulse, guiding force impulse, abrupt transition amplitude and fluctuation amplitude of guiding force were set up to evaluate the degree of borehole helix, effective push force and stability of guiding force, and to evaluate the restoring performance of drilling tool at different opening angles of upper disc valve. By analyzing the state of the drilling tool in the restoring process, the changing rule of the resultant force of outstretched hands was obtained, and compared with the test value. Finally, the changing rule of the three indexes at different opening angles of upper disc valve was obtained. The results showed that the theoretical value of the resultant push force was close to the test value. When the opening angle of upper disc valve was 180°, the restoring process was stable and efficient, and the degree of borehole helix could be reduced to the maximum extent. Three proposed evaluation indexes and the research results provide a new idea for the following overall optimization design of the vertical drilling tool.

Carrying out experimental target vehicle crash tests on actual roads is one of the important test means in the development of intelligent vehicles. In order to ensure the safety of intelligent vehicles, the chassis of the experimental target vehicle must have the ability to resist the large rolling impact. Since the rolling process of the experimental target vehicle chassis involves problems such as contact nonlinearity and geometric nonlinearity, it is difficult to design and optimize its structure based on simulation analysis alone. For this reason, the explicit nonlinear finite element method was first used to analyze the anti-rolling performance of the experimental target vehicle chassis; then, the multi-objective genetic algorithm based on the local amplification method was used to establish a multi-objective optimization model of the chassis structure with the materials as discrete variables and the geometry dimensions as continuous variables; lastly, a chassis structure optimization method with high adaptability and high fit prediction accuracy was constructed by HyperStudy software, and the chassis structure optimization scheme that met the requirements of anti-rolling performance and lightweight was obtained. The research results show that the multi-objective genetic optimization method based on the collision and rolling simulation has the characteristics of strong adaptability, accurate optimization results and high degree of multi-objective collaborative satisfaction for solving the structure optimization problem of the experimental target vehicle chassis that considers discrete-continuous variables and the highly nonlinear response surface, which can provide a reference for the structure optimization design that requires comprehensive consideration of discrete variables and multiple properties in practical applications.

Aiming to solve the problem that the protector shafting of submersible oil electric pump is easy to fracture under the full load and long-term operation condition, taking the slender series shafting of submersible oil electric pump as the study object, the influence of torsional stiffness of coupling on the torsional vibration characteristics of slender series shafting of submersible oil electric pump was analyzed. The DyRoBeS software was used to construct the torsional vibration model of the slender series shafting, and the torsional characteristics of shafting were analyzed. Combining the torsional mode and the modal torsional stress distribution, the relief groove on the protector shafting was verified to be the dangerous cross section. The relationship between torsional stiffness of the coupling and torsional stress on the dangerous cross section of shafting was studied. The analysis result showed that when the torsional stiffness of coupling 1 and 2 increased respectively in a certain proportion from 20% of the designed value to 500%, the amplification of the first order torsional vibration critical rotational speed of coupling 1 was 21%, while the amplification of coupling 2 was 64%.When the torsional stiffness of the coupling 1 was adjusted from the designed value to 40% of the designed value, the torsional stress of the dangerous section of the shaft section was reduced by about 55%. When the torsional stiffness of coupling 2 was adjusted from 300% of the designed value to 40% of the designed value, the torsional stress was reduced by about 35%. Adjusting the torsional stiffness of coupling 1 to 7.12×10⁴ Nm/rad could effectively reduce the stress on the dangerous cross section of shaft section. The research provides a reference for solving the problem of fracture of protector shaft of slender series shafting of submersible oil electric pump.

Under the specific wind load, the stress conditions of different components and parts of overhead transmission lines are very different. In severe cases, it can lead to instability of the transmission tower line system and fracture of insulator string even, which greatly affects the safety of power grid operation. Taking an overhead line in a mountainous area of Yunnan as the research object, the isotropic and anisotropic eigenvalue buckling analysis of composite insulator string mandrels was carried out based on ANSYS finite element simulation software. A new type of quadruple V-shaped insulator string was constructed. The mechanical properties of bigeminy and quadruple V-shaped insulator strings under different wind loads were compared and analyzed by introducing the coefficient of P_h/G_v (horizontal load/vertical load), and the deformation, maximum stress of the windward side and leeward side and horizontal displacement of the lowest point of V-shaped insulator strings were analyzed. The results showed that when P_h/G_v=2.34, the maximum stress on the leeward side of the V-shaped insulator string was minimal; as the P_h/G_v increased, the stress variation curve of the quadruple V-shaped insulator string was smoother than that of the the bigeminy V-shaped insulator string, and the horizontal displacement of its lowest point was smaller. When the angle between the V-shaped insulator string and the vertical plane was 10°-30°, the smaller the angle was, the more stable the overall performance of V-shaped insulator string was. The research provides a strong basis for the design improvement of V-shaped insulator string and has strong engineering practicability.

It is difficult for residents in the disaster area to obtain drinking water. In order to ensure the safety of drinking water, a mobile emergency water purification trolly with high filtration accuracy and continuous water intake is designed, which can meet the drinking water needs of small groups. Firstly, the overall structure of the mobile emergency water purification trolly with continuous water intake was designed, and the designs of its water intake device, water filteration device, water storage device and water transport device were introduced in detail. Then, the SolidWorks software was used to construct the three-dimensional model of the water transport device of the mobile emergency water purification trolly, and the finite element analysis of the placement brackets for water storage device and water filteration device was carried out through the Simulation function. Finally, the prototype of mobile emergency water purification trolly with continuous water intake was constructed, and the water intake, water filtration, water storage and water transport tests were carried out. The test results showed that this mobile emergency water purification trolly had good sealing performance and can achieve the preset functions of continuous water intake and storage; its average water transport speed reached 48 m/min, and the filtered water met the drinking standard. The designed mobile emergency water purification trolly with continuous water intake is fully functional, which has functions of drawing, filtering, storing and transporting water; it is convenient to take water directly from lake, river and reservoir; it has a large water storage capacity, which can use a 10 L TPU (thermoplastic polyurethanes) telescopic bucket; it is more labor-saving for water transportation, and the water intake, water filtration and water storage devices are integrated on the hand-held water transportation device. The mobile emergency water purification trolly with continuous water intake can effectively solve the problem of drinking water difficulties for residents in the disaster area.

In order to meet the demand of printing market for high-speed, high-quality and high-efficiency offset presses, a LYP1050 rotary offset press control system is designed. Firstly, taking the Inovance AC810 motion controller as the main controller and the Inovance IT6000 series touch screen as the human-computer interaction interface, the hardware platform of the LYP1050 rotary offset press control system was built by combining the servo drive unit. Then, the methods including the multi-axis synchronization control, the tension control of closed-loop speed and winding taper and the automatic registration control for the LYP1050 rotary offset press were proposed; at the same time, the lower computer program and human-computer interaction interface of the LYP1050 rotary offset press control system were designed. Finally, the reliability of the designed control system was verified by collecting the registration error of the LYP1050 rotary offset press prototype during actual operation. The test results showed that the registration accuracy of this rotary offset press could be controlled within ±0.05 mm, which met the registration requirements. The designed control system is safe and reliable, with good synchronization, high color registration accuracy, low failure rate, and wide versatility, which can provide references for the design of the similar rotary offset press control system.