基于RT-Thread的液压支架监控分站的设计

为提高煤矿生产的安全性和效率,降低生产成本,设计了基于嵌入式实时操作系统RT-Thread的液压支架监控分站。该分站通过CAN总线将综采工作面液压支架的工作数据上传到主站并接收主站下达的指令;此外,通过支架控制器可以实现对液压支架的远程控制。软件设计利用信号量和事件集进行线程间通信同步;同时采用多线程优先级抢占调度机制,实现任务的并发运行。实验证明,该分站具有精度高、可靠性强和实时响应等特点,达到工程实际应用需求。

An HLA/RTI Architecture Based on Multi-thread Processing

In order to improve the real-time performance of the real-time HLA(high level architecture) in the application of massive data communication volume,multi-thread processing was adopted,thread pool structure was introduced into the system,different threads to handle corresponding message queues was utilized to respond different message requests.Furthermore,an allocation strategy of semi-complete deprivation of priority was adopted,which reduces thread switching cost and processing burden in the system,provided that the message requests with high priority can be responded in time,thus improves the system's overall performance.The design and experiment results indicate that the method proposed in this paper can improve the real-time performance of HLA in distributed system applications greatly.

Multi-threaded Fast Distance Field Computation Using Spatial Partition

This article describes three algorithms for distance field generation on triangulated model: brute force algorithm, single-threaded algorithm based on spatial partition and multi-threaded algorithm based on spatial partition. Spatial partition algorithm use equidistant network divide the bounding box into equal-sized cubes, calculates the maximum and minimum distances between the sample point and each of the small cubes,taking the minimum value from the maximum distance as the minimum distance from the sample point to the model named d1, comparing d1 with the distance from sample point to every little cube's minimum distance d2, if d1 <d2, the sample point's distance to all triangles inside this cube are greater than d1, skip this cube, otherwise, calculated the distance from the point to all the triangles intersect with the cube, then alternative d1 with the minimum value, circulate all small cubes intersect with the model. Comparing the calculation results, it can be seen that the algorithm about the multi-threaded distance field relative to the other two algorithms in computational speed is greatly improved especially for complex models.

Dynamically Translating Binary Code for Multi-Threaded Programs Using Shared Code Cache

mc211vm is a process-level ARM-to-x86 binary translator developed in our lab in the past several years. Currently, it is able to emulate singlethreaded programs. We extend mc211vm to emulate multi-threaded programs. Our main task is to reconstruct its architecture for multi-threaded programs. Register mapping, code cache management, and address mapping in mc2llvm have all been modified. In addition, to further speed up the emulation, we collect hot paths, aggressively optimize and generate code for them at run time. Additional threads are used to alleviate the overhead. Thus, when the same hot path is walked through again, the corresponding optimized native code will be executed instead. In our experiments, our system is 8.8X faster than QEMU （quick emulator） on average when emulating the specified benchmarks with 8 guest threads.

Design of cable tester based on multi-thread parallel testing technology

In order to realize the efficiency, reliability and safety tests on the complex cable network of an electronic system, an efficient cable network resistance tester is designed. Firstly, the design background and hardware structure are briefly described. Then aiming at the multi task parallelism considering real time measurement of parameters and real time control of the system in the tester testing, a real time muhi task control software is developed by using multi thread testing technology in parallel test to realize multi task complex control. Finally, the least squares method is used to improve the test accuracyof the tester. The test results show that the test error is basically within 0.3%, and the test speed can reach 345 point/min.

Efficient computation of Hash Hirschberg protein alignment utilizing hyper threading multi-core sharing technology

Due to current technology enhancement,molecular databases have exponentially grown requesting faster efficient methods that can handle these amounts of huge data.There-fore,Multi-processing CPUs technology can be used including physical and logical processors(Hyper Threading)to significantly increase the performance of computations.Accordingly,sequence comparison and pairwise alignment were both found contributing significantly in calculating the resemblance between sequences for constructing optimal alignments.This research used the Hash Table-NGram-Hirschberg(HT-NGH)algo-rithm to represent this pairwise alignment utilizing hashing capabilities.The authors propose using parallel shared memory architecture via Hyper Threading to improve the performance of molecular dataset protein pairwise alignment.The proposed parallel hyper threading method targeted the transformation of the HT-NGH on the datasets decomposition for sequence level efficient utilization within the processing units,that is,reducing idle processing unit situations.The authors combined hyper threading within the multicore architecture processing on shared memory utilization remarking perfor-mance of 24.8%average speed up to 34.4%as the highest boosting rate.The benefit of this work improvement is shown preserving acceptable accuracy,that is,reaching 2.08,2.88,and 3.87 boost-up as well as the efficiency of 1.04,0.96,and 0.97,using 2,3,and 4 cores,respectively,as attractive remarkable results.

Preload Control Method of Threaded Fasteners:A Review

Threaded fasteners are one of the most commonly used connection methods for mechanical structures.Its primary function is to generate appropriate clamping forces and fasten the connected parts.An inappropriate preload can cause loosening,fatigue fracture,and other problems.This will affect the safety and reliability of mechanical equipment.The precise control of the preload has become a critical issue in mechanical assembly processes.Over the past few decades,various tightening measures and methods have been proposed to address this issue.However,many problems continue to exist with practical applications that have not been reviewed comprehensively and systematically.First,various control methods were summarized systematically,and their advantages and disadvantages in engineering applications were analyzed.Torque control is the most widely used tightening method owing to its simple operation and low cost.Therefore,the research on the torque control method was summarized systematically from three aspects:the torque-preload correlation formula,effective friction radius,and friction characteristics during tightening.In addition,the special circumstances that may increase preload uncertainty were discussed.Finally,based on a summary of the current research status,the prospects for future research were discussed.This study would aid researchers in extensively understanding the problems in preload control.

Dental Precautions for the Golden Thread Lift Procedure

In cosmetic surgery, golden threads have been used in thread lift procedures, wherein golden threads are placed under the skin of the neck and chin. These are mainly applied in the maxillofacial region adjacent to the sites of dental treatment to achieve cosmetic benefits. However, as dentists typically lack sufficient knowledge about the golden thread lift procedure, it may present a challenge to dental examinations and treatments. It is therefore crucial for dentists to have a comprehensive understanding of the procedure. This case report covers our experience with the dental examination of a patient with golden threads. We emphasize the dental complications and precautions that should be taken for such cases. These golden threads are made of pure gold, nonabsorbable, and can be broken. These can obstruct dental examination, as well as cause metal allergies and foreign body granulomas. Additionally, it is difficult to completely remove these threads when they break apart. In the future, since more patients are expected to undergo this procedure, it is possible to encounter these golden threads as artifacts on imaging. Therefore, it is important to educate dentists about the golden thread lift procedure and its dental implications. It is also imperative to determine whether the patient has undergone the golden thread lift procedure in the medical questionnaire prior to the magnetic resonance imaging examination. Thus, dentists should be able to conduct a detailed interview with the patient, determine the feasibility of examination or treatment, and communicate this assessment to the patient.

Roller Screw and Threaded Chain Speed Reducer: An Experimental Evaluation

We are developing a speed reducer that can be considered a transformation of a worm gear reducer: the worm is replaced by an inverted roller screw, and the gear is replaced by a threaded chain drive. This configuration lessens wear, increases load capacity, and improves efficiency. The threaded chain consists of nut-shaped links. This paper presents the results of tests carried out on a prototype with a reduction ratio of 46.

基于RT-Thread的可信软件栈的设计和实现

针对基于Linux和TCG软件栈(Trusted computing group Software Stack,TSS)的复杂性问题,提出一种轻量级的可信软件栈。分析了TSS的基本结构与TSS在嵌入式系统的局限,总结出基于嵌入式系统的可信软件栈设计需求,设计出软件栈命令调用的机制和软件栈的结构。此外,分析了TSS密钥管理缓存算法,在flash中定义一块密钥槽空间,方便密钥管理中直接访问,阐述密钥生成的逻辑过程,实现面向嵌入式系统的可信软件系统。经实验验证,该软件栈可以结合RT-Thread实时系统实现基本的可信计算功能。

基于RT-Thread的卫星导航控制系统研究

随着制造业的发展,自动引导车被广泛应用于现代工业领域,由于作业环境复杂程度变高,对车辆控制系统硬件的稳定性、灵活性,软件系统的实时性、模块化程度有了更高要求。从自动引导车的需求出发,对导航控制系统的硬件及软件进行了设计,后针对路径规划与路径追踪模块,提出了一种路径规划与追踪控制方法,通过输入不同的横向误差与速度进行指定模糊规则,最终得到合适的预瞄距离,从而使车辆实现自适应预瞄距离的功能,提高车辆的自适应能力。试验结果证明了设计的可行性,为后续自动引导车的控制系统研究提供参考。

基于RT-thread的精确时间同步系统设计

分布式智能采集终端需要一致的时间基准,用于多种数据和事件的时间标记。为满足智能采集终端对高精度时间同步的需求,选择IEEE 1588精确时间同步协议实现时间同步;设计基于纯国产32 bit双核微控制器HPM6750和以太网收发器RTL8211FS(I)-VS的精确时间同步系统,选用国产开源嵌入式实时操作系统RT-thread操作系统,实现在物理层获取时间戳来运行IEEE 1588协议;构建测试平台对该时间同步系统进行主从时钟同步精度测试。测试结果表明,设计在物理层获取时间戳时达到的时间同步精度在±250 ns以内,与在数据链路层获取时间戳时达到±10μs的时间同步精度相比较,有效提高了时间同步精度,可广泛应用于对时间同步精度有较高要求的智能采集终端。

基于 RT-Thread 的玉米对行收获控制系统 研发与测试

为提高玉米机械化收获效率,减轻驾驶员劳动强度,研发玉米收获对行控制系统。该系统包括玉米边界行感知模块和对行控制模块,采用激光雷达获取玉米行点云数据,提出基于STM32处理器和RT-Thread实时操作系统的点云数据快速分析处理方法,实现玉米行边界点的提取,通过边界点计算得到横向偏差;设计系统通信拓扑架构,实现感知、处理、对行控制模块之间的高效通信。对该系统的性能开展田间试验验证,结果表明:收割机与玉米行实际边界线的平均横向偏差为0.06 m,最大横向偏差为0.126 m,满足玉米对行收获作业要求,为玉米对行收获提供一定的参考。

一种基于RT-Thread的室内环境监测系统设计

为了提高传统环境监测系统多任务协调与实时性的水平,设计了一款以STM32F103ZET6微控制器为核心的监测系统。该系统利用RT-Thread实时操作系统来进行多任务调度,实现温湿度、空气质量、光照强度等参数的采集,并通过窄带物联网上传至阿里云平台进行观测。经测试,监测温度误差不超过0.5℃,空气质量误差小于2%,检测时间低于0.5秒,相较于传统监测系统实时性更好。

基于RT-Thread的温湿度数据采集监测系统设计

温湿度数据的采集和监测在各行各业中发挥着重要作用。本文基于RT-Thread设计了一个分布式温湿度采集监测系统。该系统以STM32开发板为主控模块,在芯片中嵌入RT-Thread实时操作系统,可实时采集分布式节点的温湿度数据,并通过无线网络将数据上传至OneNET云平台。该系统提高了数据采集的实时性,实现了温湿度数据的可视化显示和远程实时监测功能。

实时操作系统ThreadX剖析

ThreadX是一个成熟的商用强实时嵌入式操作系统,被广泛应用于消费电子、航空航天、通信与医疗等应用领域中。通过对ThreadX所提供的服务与开发组建、线程调度算法、线程同步与通信机制、中断服务以及多处理器支持等方面的分析,可知ThreadX以轻量级的规模,提供了良好的实时性、可靠性与易用性,是嵌入式应用中一个不错的RTOS选择。

RT-Thread操作系统的电池管理系统设计

为了保证电池在充放电过程中的安全,针对目前电池管理系统存在可移植性差、不便于功能扩展等问题,提出一种智能电池管理系统。系统采用国产嵌入式实时操作系统RT-Thread,并选用STM32作为主控制器芯片,使整个系统的监控、调试更加方便。测试结果表明,该系统可以实时监控电池的充放电过程,预留的接口可以方便以后做功能扩展。

RT-Thread和Qt的可视化印花机控制系统设计

为了提高印花机控制系统的自动化水平,针对当前印花机控制系统功能单一、稳定性差、缺少直观的数据显示和命令操作界面等缺陷,提出一种基于上下位机模式的可视化印花机控制方案。该方案采用嵌入式实时操作系统RT-Thread实现下位机模块的任务调度,采用Qt应用程序框架设计上位机的人机交互图形界面,并通过CAN总线连接下位机进行印花电机的监控。实验证明,该方案不仅提高了系统的可靠性和操作的直观性,而且有利于系统的进一步改进与升级。

面向动目标围捕的Multi-UUV编队协调控制研究

针对动目标围捕过程对Multi-UUV编队结构的灵活性要求较高的问题,基于欠驱动UUV的数学模型,在目标轨迹能够准确预测的前提下,改进了协调编队运动控制器。协调编队运动控制器的控制目标是在Multi-UUV编队跟踪并围捕动目标过程中,避免Multi-UUV之间,UUV与障碍物以及UUV与动目标之间的碰撞并以稳定的编队结构围捕动目标。将控制器设计过程分解为运动学控制和动力学控制。在运动学控制部分,实现动目标跟踪、UUV之间避撞及UUV偏航角误差为零的控制目标。在动力学控制部分,应用反步法设计实际的控制输入。仿真案例验证了协调运动控制器在动目标围捕中的有效性。

MSP432的RT Thread操作系统移植

RT Thread是一个组件丰富、功能强大、可裁剪性好的开源嵌入式操作系统,而MSP432兼具高性能和低功耗优点,在医疗、能源等领域应用广泛,两者结合必将使得开发更加高效、便捷。但是,关于RT Thread向MSP432单片机移植的详细过程尚未有现成方案。为此,本文给出了RT Thread操作系统在MSP432P401R上移植的具体方法,通过剪裁源码、修改配置文件、更改系统时钟等操作进行适配并移植。实验结果表明,RT Thread系统成功移植到MSP432并能正常运行,具备任务管理、调度以及中断及异常管理等功能。