针对家用超声治疗仪存在谐振频率易漂移及精度低等问题, 该文提出了一种将模糊控制器、比例、积分、微分(PID)控制器和锁相环技术结合的复合跟踪策略。通过直接数字式频率合成(DDS)技术结合STM32L151产生超声信号, 利用T型网络进行阻抗匹配, 对超声治疗仪性能进行测试。实验结果表明, 该治疗仪声-电转换效率高, 输出的超声波具有精度高, 不易失谐等优点。

基于无人机飞行平台的定位与测姿系统(Position and oricntation system, POS)是通过差分GNSS高精度定位技术与INS导航技术集成, 为基于直接地理参考的航空遥感提供位置和姿态基准, 是获取高质量遥感成像的关键。针对轻小型无人机采用的低精度IMU, 对其误差模型展开研究分析, 建立24阶卡尔曼滤波器, 最后采用GNSS/INS松组合模式得到高精度POS数据。实测数据表明, 将此误差模型下获取的POS数据与无人机激光雷达扫描数据进行融合处理, 可满足激光点云精度需求, 有效降低机载激光扫描系统成本。

机载LiDAR(Light detection and ranging)扫描系统由激光扫描仪(LS)、全球卫星导航系统(GNSS)和惯性导航系统(INS)组成，无论是在三维测量还是无人驾驶中有着广泛的实用价值和应用前景。其中扫描系统的安装误差角是影响激光点云精度的主要因素之一。提出一种无地面控制点的机载LiDAR扫描系统的安装误差参数标定方法。通过重复扫描同名点来推导扫描系统安置参数标定模型，最后再使用最小二乘迭代法求解出标定参数的最优值。通过无人机载激光扫描系统实验验证了方法的合理性和有效性，可以很明显的提高扫描数据生成的点云质量，具有一定的可行性和实用性。

To solve the large noise problem for the lowprecision gyroscopes in micro-electro mechanical systems (MEMS) of inertial navigation system, an improved noise reduction method, based on the analyses of the fast Fourier transformation (FFT) noise reduction principle and the simple wavelet noise reduction principle, was proposed. Furthermore, the FFT noise reduction method, the simple wavelet noise reduction method and the improved noise reduction method were comparatively analyzed and experimentally verified in the case of the constant rate and dynamic rate. The experimental analysis results showed that the improved noise reduction method had a very good result in the noise reduction of the gyroscope data at different frequencies, and its performance was superior to those of the FFT noise reduction method and the simple wavelet noise reduction method.