钛合金球形贮箱异常声发射信号分析

针对钛合金贮箱制造检测工艺过程中经常发生的质量偏差,通过对球形钛合金贮箱两例异常声发射幅度、时间历程以及定位结果等进行综合分析。结果表明,声发射检测技术对贮箱制造工艺状态偏差具有很强的敏感性,声发射检测结果不仅能反映贮箱产品的强度质量,还能反映贮箱制造工艺状态的稳定性和偏差。     

飞行模拟机的某型涡扇发动机起动模型研究

为了建立适用于飞行模拟机的发动机起动模型,对涡扇类发动机起动过程的建模和仿真方法进行了研究,提出了飞行模拟机起动模型的建模基本原则,以此为指导,基于部件级建模方法建立了主导发动机正常起动动态性能的主要特性模型,并通过构建故障因子建立了典型故障模型,实现了发动机正常起动和起动过程中的故障模拟。正常起动仿真和故障仿真结果与测试数据的对比表明,所建立的正常起动模型正确地反映了发动机在各起动阶段的加速性能,故障模型很好的再现了故障逻辑和故障效应,满足了用于飞行模拟机的发动机起动仿真要求。     

RASC雷达模拟机故障检测

叙述了ＲＡＳＣ雷达模拟机的组成结构及对系统故障检测的一般方法。该方法对其它计算机系统及模拟机系统的故障检测有可取之处。     

飞机飞行模拟机鉴定性能标准分析

简要介绍了飞机飞行模拟设备的鉴定和使用规则的主要内容,着重对飞机飞行模拟机鉴定性能的标准进行了分析．给出了客观鉴定标准与数据试飞之间的关系。     

飞行模拟器逼真度与飞行试验

提出了飞行模拟器逼真度与飞行试验的关系,介绍了飞行模拟器逼真度的定义,模拟逼真度的基本要求及与飞行模拟器规范的关系,讨论了模拟逼真度的研究范围和飞行模拟器逼真度对飞行试验所记录数据精度的一般要求及飞行数据的编制原则。     

高动态GPS卫星信号模拟器电离层延迟误差模拟方法研究

电离层延迟误差是GPS测量中非常重要的一项误差源,也是高动态GPS卫星信号模拟器要解决的一项关键技术。电离层延迟误差与目标的空间位置有关,在分析地面用户和空问用户不同电离层延迟误差修正方法的基础上,研究了卫星信号模拟器电离层延迟误差产生的途径,并给出了相应的数学模型,解决了不同应用环境下导航电8个电离层修正参数的计算问题,通过仿真计算,验证了本所提出的电离层延迟计算模型的正确性。     

Experimental investigation on static/dynamic characteristics of a fast-response pressure sensitive paint

An optical-based technique using Pressure-Sensitive Paint(PSP) is a promising method to measure the distribution of surface pressure on an aerodynamic model. The static and dynamic characteristics of a fast-response PSP that is developed in the Chinese Academy of Sciences(CAS)are analyzed and tested to serve as the basis for experiments on unsteady surface measurement using a fast-response PSP. Two calibration systems used for this study are set up to investigate the temperature dependency, response time, and resolution. A data processing method, used for dynamic data, is analyzed and selected carefully to determine the optimum signal. Results show that the fastresponse PSP can be used normally at temperatures from 25 ℃ to 80 ℃. The effect of temperature on the accuracy of the measurement must be considered when temperatures are beyond the temperature range of 30–40 ℃. The dynamic calibration device with a solenoid valve can achieve a pressure jump within a millisecond order. The resolution is determined by the signal-to-noise ratio of the photo-multiplier tube. Results of the measurement show that the response time of the PSP decreases with a large pressure variation, and the response time is below 0.016 s when the pressure variation is under 40 kPa.     

Friction compensation for low velocity control of hydraulic flight motion simulator: A simple adaptive robust approach

Low-velocity tracking capability is a key performance of flight motion simulator (FMS), which is mainly affected by the nonlinear friction force. Though many compensation schemes with ad hoc friction models have been proposed, this paper deals with low-velocity control without friction model, since it is easy to be implemented in practice. Firstly, a nonlinear model of the FMS middle frame, which is driven by a hydraulic rotary actuator, is built. Noting that in the low velocity region, the unmodeled friction force is mainly characterized by a changing-slowly part, thus a simple adaptive law can be employed to learn this changing-slowly part and compensate it. To guarantee the boundedness of adaptation process, a discontinuous projection is utilized and then a robust scheme is proposed. The controller achieves a prescribed output tracking transient performance and final tracking accuracy in general while obtaining asymptotic output tracking in the absence of modeling errors. In addition, a saturated projection adaptive scheme is proposed to improve the globally learning capability when the velocity becomes large, which might make the previous proposed projection-based adaptive law be unstable. Theoretical and extensive experimental results are obtained to verify the high-performance nature of the proposed adaptive robust control strategy.