lianghu3124的专栏

Abstract— In recent years there have been excellent results in Visual-Inertial Odometry techniques, which aim to compute the incremental motion of the sensor with high accuracy and robustness. However these approaches lack the capability to close loops, and trajectory estimation accumulates drift even if the sensor is continually revisiting the same place. In this work we present a novel tightly-coupled Visual-Inertial Simultaneous Localization and Mapping system that is able to close loops and reuse its map to achieve zero-drift localization in already mapped areas. While our approach can be applied to any camera configuration, we address here the most general problem of a monocular camera, with its well-known scale ambiguity. We also propose a novel IMU initialization method, which computes the scale, the gravity direction, the velocity, and gyroscope and accelerometer biases, in a few seconds with high accuracy. We test our system in the 11 sequences of a recent micro-aerial vehicle public dataset achieving a typical scale factor error of 1% and centimeter precision. We compare to the state-of-the-art in visual-inertial odometry in sequences with revisiting, proving the better accuracy of our method due to map reuse and no drift accumulatio

Abstract: Current approaches for visual-inertial odometry (VIO) are able to attain highly accurate state estimation via nonlinear optimization. However, real-time optimization quickly becomes infeasible as the trajectory grows over time; this problem is further emphasized by the fact that inertial measurements come at high rate, hence leading to fast growth of the number of variables in the optimization. In this paper, we address this issue by preintegrating inertial measurements between selected keyframes into single relative motion constraints. Our first contribution is a preintegration theory that properly addresses the manifold structure of the rotation group. We formally discuss the generative measurement model as well as the nature of the rotation noise and derive the expression for the maximum a posteriori state estimator. Our theoretical development enables the computation of all necessary Jacobians for the optimization and a-posteriori bias correction in analytic form. The second contribution is to show that the preintegrated IMU model can be seamlessly integrated into a visual-inertial pipeline under the unifying framework of factor graphs. This enables the application of incremental-smoothing algorithms and the use of a structureless model for visual measurements, which avoids optimizing over the 3D points, further accelerating the computation. We perform an extensive evaluation of our monocular VIO pipeline on real and simulated datasets. The results confirm that our modelling effort leads to accurate state estimation in real-time, outperforming state-of-the-art approaches.

In this paper, we present a novel method to fuse observations from an inertial measurement unit (IMU) and visual sensors, such that initial conditions of the inertial integration, including gravity estimation, can be recovered quickly and in a linear manner, thus removing any need for special initialization procedures. The algorithm is implemented using a graphical simultaneous localization and mapping like approach that guarantees constant time output. This paper discusses the technical aspects of the work, including observability and the ability for the system to estimate scale in real time. Results are presented of the system, estimating the platforms position, velocity, and attitude, as well as gravity vector and sensor alignment and calibration on-line in a built environment. This paper discusses the system setup, describing the real-time integration of the IMU data with either stereo or monocular vision data. We focus on human motion for the purposes of emulating high-dynamic motion, as well as to provide a localization system for future human–robot interactio

介绍了在 labvIEW环境下利用labSQL用户开发的数据库访问工具包访问 数据库接口的方法， 并详细论述建立数据库连接模块、 关闭数据库模块和操作数据库模块的实现过程， 给出了应用实例。将该方法应用于某实时监控系统， 对故障诊断数据库进行访问管理,取得了较好的效果。

labview编写的用户管理程序，包括用户添加，更改用户，输入判断等-prepared labview user management procedures, including adding users, changing users, such as input to determine 需要labSQL的支持

网络大牛编写的用Microsoft speech SDK 5.1在LabVIEW中实现TTS语音合成功能的例程，非常感谢他的贡献，让我的程序更加绘声绘色。

与文本无关的嵌入式声纹识别门禁系统 论文，看了众多论文，这篇比较有用

MIC函数总结，自己在网页上收集整理的，来自“逍遥散人の家”

一种改进的LBG算法在声纹识别中的应用,很不错的论文奥。实验结果达到98%

DirectSound 是微软多媒体技术DirectX 的组成部分，封装了大量音频处理 API 函数，它可以提供快速的混音、硬件加速功能，并且可以直接访问相关设备， 当然，最主要的是它提供的功能与现有的设备驱动程序保持兼容性。 DirectSound 允许进行波型声音的捕获、重放，也可以通过控制硬件和相应的 驱动来获得更多的服务。 DirectSound 的优势当然和DirectX 的其它组件一样——速度，它允许你最大 效率的使用硬件，并拥有良好的兼容性。

PIC18系列中档单片机数据手册，做过笔记，比较好用，适用于大多数PIC18系列的单片机，只是外设、寄存器等地方有细微差别，需注意！

稍微比那个35页的教程新一点，是multisim 2001的入门教程

Agenda Overview of the some of the Nios training given in Boot Camp, as well as looking into more advanced topics. This class is broken down into four parts: − Hardware Development − Software Development − Software Debug − User Peripherals/Custom Instructions

本书共分为十章，以下是其他各章介绍，了解这些可以帮助读者取舍内容。 第二章以Altera 公司的Nios 开发板为基础，介绍了一个典型Nios 系统的设计过程，由于其中绝大部分工作是在PC 机上完成，更多情况下类似于一份软件操作说明，所以读者即使在没有Altera 公司的开发板的情况下，仍然可以通过本章了解完整的开发过程。通过本章，初学者可以对SOPC Builder 开发环境有一定的感性认识，并可在后面的学习中比照本章学习。而对于已经具有相当设计经验的读者，可以略过本章。 第三章介绍3.0 版本的32 位Nios CPU 内部结构。包括寄存器组织、流水线结构和汇编指令等。 第四章介绍Avalon 总线规范。Avalon 总线是一种相对简单的片上总线结构，主要用于连接CPU 和片内外设。但它仍然包含了相当多的高级特性，包括支持延迟读操作，流模式传输以及并发多主设备访问等。这些特性极大的扩展了Avalon 总线的适应能力并能够有效提升系统性能。 第五章介绍Nios 处理器的软件设计流程与方法，包括Nios SDK Shell 环境以及软件开发包（SDK）的结构。 第六章介绍SOPC Builder 中的IP 组织方法，并细致说明了四个常用的外设。其他外设的使用基本类似，用户可以参考Altera 公司的相关文档。 第七章讲述Nios 处理器的中断处理机制以及如何在软件中书写中断服务程序。特别是以UART 为例，详细地介绍了中断向量的安装与中断的不同处理方法。 第八章介绍Nios 处理器的调试手段。Altera 公司并不提供All in one 的编译和调试工具，只提供基本的监控程序或者对调试硬件支持。因此用户如果需要更优秀的调试工具，可以从第三方那里得到，如Mentor 公司的Codelab 就是一款比较优秀的调试软件。 第九章介绍Nios 处理器的高级特性，这些特点有效地提升了系统性能，并反映了片上总线地特点。 第十章介绍即将发布的Nios II CPU，用户可以通过介绍了解Nios 处理器的发展方向以及一些最新的特点。

vfw vidio for windows 视频捕捉教材

3D摄像头驱动，是关于两个摄像头从不同视角图像的合成

OpenGL是近几年发展起来的一个性能卓越的三维图形标准，它是在SGI等多家世界闻名的计算机公司的倡导下，以SGI的GL三维图形库为基础制定的一个通用共享的开放式三维图形标准。目前，包括Microsoft、SGI、IBM、DEC、SUN、HP等大公司都采用了OpenGL做为三维图形标准，许多软件厂商也纷纷以OpenGL为基础开发出自己的产品，其中比较著名的产品包括动画制作软件Soft Image和3D Studio MAX、仿真软件Open Inventor、VR软件World Tool Kit、CAM软件ProEngineer、GIS软ARC/INFO等等。值得一提的是，随着Microsoft公司在Windows NT和最新的Windows 95中提供了OpenGL标准及OpenGL三维图形加速卡的推出，OpenGL将在微机中有广泛地应用，同时也为广大用户提供了在微机上使用以前只能在高性能图形工作站上运行的各种软件的机会。……