Theory and experiments in SmartNav rover navigation

This paper describes theoretical and experimental results using the SmartNav rule-free fuzzy rover navigation system. SmartNav divides the terrain perceived by the rover into a number of circular sectors, and evaluates each sector using goal and safety preference factors to differentiate between preferred and unpreferred terrain sectors. The goal-preference factor is used to make sector evaluation based on the sector orientation relative to the designated goal position. The safety-preference factors are used to make sector evaluations on the basis of the sector local and regional terrain hazards. Three methods are developed to blend the three sector evaluations in order to find the effective preference factor for each sector. Two sector selection methods are then described in which the sector preference factors are used to find the heading command for the rover. The rover speed command is also computed based on the goal distance and safety-preference factor of the chosen sector. The above navigation steps are continuously repeated throughout the rover motion. Experimental results are presented to demonstrate the navigational capabilities of SmartNav using a commercial Pioneer 2AT rover traversing a simulated Martian terrain at the JPL Mini Mars Yard.

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Experiences in Improving Flight Software Development Processes

In 2001, the Jet Propulsion Laboratory (JPL) initiated a software process improvement effort. In 2004, JPL began the Multimission System Architecture Platform (MSAP) project and designated it as part of this effort. In 2007, JPL's Engineering and Science Directorate, which controls the MSAP project's technical development, achieved CMMI Staged Maturity Level 3.1 This article describes the impacts of the CMMI rating and the JPL process improvement effort on the MSAP project's software engineering and assurance organizations.     

Perception‐aware autonomous mast motion planning for planetary exploration rovers

Highly accurate real‐time localization is of fundamental importance for the safety and efficiency of planetary rovers exploring the surface of Mars. Mars rover operations rely on vision‐based systems to avoid hazards as well as plan safe routes. However, vision‐based systems operate on the assumption that sufficient visual texture is visible in the scene. This poses a challenge for vision‐based navigation on Mars where regions lacking visual texture are prevalent. To overcome this, we make use of the ability of the rover to actively steer the visual sensor to improve fault tolerance and maximize the perception performance. This paper answers the question of where and when to look by presenting a method for predicting the sensor trajectory that maximizes the localization performance of the rover. This is accomplished by an online assessment of possible trajectories using synthetic, future camera views created from previous observations of the scene. The proposed trajectories are quantified and chosen based on the expected localization performance. In this study, we validate the proposed method in field experiments at the Jet Propulsion Laboratory (JPL) Mars Yard. Furthermore, multiple performance metrics are identified and evaluated for reducing the overall runtime of the algorithm. We show how actively steering the perception system increases the localization accuracy compared with traditional fixed‐sensor configurations.     

Enabling collaborative engineering and science at JPL

We examine the issue of distributed collaboration at the Jet Propulsion Laboratory (JPL). With the goals of “faster, better, cheaper” missions, an efficient, seamless collaboration capability is critical to future JPL space exploration missions. We assert that the current capabilities for distributed collaboration internal to JPL, as well as external, are unsatisfactory. This paper provides a vision of greatly enhanced distributed collaboration capabilities in the near future and into the far future. Our vision focuses primarily on distributed collaborative engineering and science.We believe enhanced capabilities are necessary in two collaborative paradigms: the virtual conference and the shared virtual workspace. We describe these collaborative paradigms, and discuss the tools that exist and the additional capability necessary to achieve the collaborative vision with respect to the types of data we typically work with at JPL. We identify the following types of data frequently exchanged in collaborative activities: project planning data, design data, notes/documentation, communication data, analysis/performance data, verification data and scientific data. Our analysis shows that at present there is good GroupWare support for project planning data and notes/documentation data. Support is improving for design data. Other data types have no or sporadic support at best.     

Bootstrap: fine-tuning process assessment

Bootstrap was a project done as part of the European Strategic Program for Research in Information Technology. Its goal was to develop a method for software-process assessment, quantitative measurement, and improvement. In executing that goal, Bootstrap enhanced and refined the Software Engineering Institute's process-assessment method and adapted it to the needs of the European software industry-including nondefense sectors like banking, insurance, and administration. This adaptation provided a method that could be applied to a variety of software-producing units, small to medium software companies or departments that produce software within a large company. Although the Bootstrap project completed in 1993, its attribute-based method for assessing process maturity continues to evolve. The authors describe the elements of the method, how it can be used to determine readiness for ISO 9001 certification, and how it was applied in two instances to substantially improve processes     

Distributed fault-tolerant real-time systems: the Mars approach

The authors describe the Maintainable Real-Time System, a fault-tolerant distributed system for process control, developed under the Mars project started in 1980 at the Technische Universitat Berlin. They explore the characteristics of distributed real-time systems and then present the Mars approach to real-time process control, its architectural design and implementation, and one of its applications. The authors focus on the maintainability of the Mars architecture, describe the Mars operating system, and discuss timing analysis. The control of a rolling mill that produces metal plates and bars is examined     

MAPGEN: mixed-initiative planning and scheduling for the Mars Exploration Rover mission

The Mars Exploration Rover mission is one of NASA's most ambitious science missions to date. Launched in the summer of 2003, each rover carries instruments for conducting remote and in site observations to elucidate the planet's past climate, water activity, and habitability. Science is MER's primary driver, so making best use of the scientific instruments, within the available resources, is a crucial aspect of the mission. To address this criticality, the MER project team selected MAPGEN (mixed initiative activity plan generator) as an activity-planning tool. MAPGEN combines two existing systems, each with a strong heritage: the APGEN activity-planning tool from the Jet Propulsion Laboratory and the Europa planning and scheduling system from NASA Ames Research Center. We discuss the issues arising from combining these tools in this mission's context. MAPGEN is the first AI-based system to control a space platform on another planet's surface.     

Mars exploration rover mobility development

The Mars Exploration Rover (MER) Project was launched in mid-2000 to land two mobile exploration platforms at different science targets on the red planet. The centerpiece of each mission is the rover and its scientific payload. Spirit and Opportunity are identical vehicles, and each carries the same science payload and engineering subsystems. NASA's current Mars program is once again focused on missions to the Martian surface to answer fundamental questions of the extent Mars ever supported a liquid water environment on its surface, and hence the planet's ability to have sustained life.     

智能水利工程评价体系及方法研究

智能水利工程的设计方案是当前水利行业研究和实践的热点,工程智能化水平的评价体系也是工程建设者最为关心的问题。针对智能水利工程的概念内涵进行分析,结合行业需求提出水利工程智能化建设的目标是在工程自动化控制的基础上,进一步通过数学模型、智能化算法赋予水利工程自适应和自主优化决策的能力;围绕水利工程智能化建设目标,重点研究提出由数字化、自动化和智能化 3 种类型共 19 个指标组成的评价体系及评价方法。运用本评价体系及评价方法,不仅可以整体性地量化水利工程的智能化建设水平,也可以有效引导智能水利工程设计和运行管理的技术发展方向,促进工程智能化建设的创新发展,从而全力支撑新时代水利工程高质量的建设和运行管理。     

Computer Vision on Mars

Increasing the level of spacecraft autonomy is essential for broadening the reach of solar system exploration. Computer vision has and will continue to play an important role in increasing autonomy of both spacecraft and Earth-based robotic vehicles. This article addresses progress on computer vision for planetary rovers and landers and has four main parts. First, we review major milestones in the development of computer vision for robotic vehicles over the last four decades. Since research on applications for Earth and space has often been closely intertwined, the review includes elements of both. Second, we summarize the design and performance of computer vision algorithms used on Mars in the NASA/JPL Mars Exploration Rover (MER) mission, which was a major step forward in the use of computer vision in space. These algorithms did stereo vision and visual odometry for rover navigation and feature tracking for horizontal velocity estimation for the landers. Third, we summarize ongoing research to improve vision systems for planetary rovers, which includes various aspects of noise reduction, FPGA implementation, and vision-based slip perception. Finally, we briefly survey other opportunities for computer vision to impact rovers, landers, and orbiters in future solar system exploration missions.     

The Mars exploration plans of ESA

In the framework of its Aurora Exploration Program, the European Space Agency (ESA) has initiated the ExoMars Project. Aside from searching for traces of life at and near the Martian surface, ExoMars aims to characterize the Martian geochemistry and water distribution at various locations, improve the knowledge of the Mars environment and geophysics, and identify possible hazards for future missions. Beyond the ExoMars Project, there is a strong scientific and technical interest in Europe to participate in an international Mars Sample Return (MSR) mission. ESA's overall approach to MSR includes a combination of system studies, technology development work, and the identification of capability development approaches including the consideration of demonstration missions. In the longer term, the approach intends to allow the strategic down-selection of specific areas in which Europe can play a strategic role in the eventual MSR mission.     

A practical use of model checking for synthesis: generating a dam controller for flood management

Program synthesis with automated methods has been an active research area for many years; however, we still lack well‐known and accepted techniques for this software engineering task. In this case, the design space to be considered is infinite, even when the solution is restricted to software that meets the requirements. In this paper we propose the use of model checking (MC) techniques to automatically synthesize controllers. Given a goal in the evolution of a plant, MC can be used to search for acceptable software controllers that enable the plant to evolve as desired. We also develop a realistic application in the context of a joint project with a major water reservoir management company. This application generates controllers for dam management during flood seasons. The controllers give the proper orders (open or close the outflow elements) at precise times in order to avoid disasters and to preserve the water level in the dam. Copyright © 2011 John Wiley & Sons, Ltd.     

Making Peace with the Rising Costs of Writing Technologies: Flexible Classroom Design as a Sustainable Solution

In a challenging economy where budgets for academic programs seem to shrink each year, writing programs face serious economic challenges. When fiscal challenges are paired with the ever-changing nature of writing technologies and the need to update classroom technologies on a regular basis, the challenges can seem insurmountable. In this article the authors discuss the multiple phases of a classroom redesign project where first-year composition students used their own laptop computers in a flexible classroom, which included mobile furnishings, mobile whiteboards, and multiple LCD screens for projection. The purpose of the project was to design a space that was economically sustainable and would better meet the needs of composition instructors and students. To meet that goal, the First-Year Writing Program partnered with the institution's IT and Design Services to develop the flexible classroom model. The flexible classroom project sought to answer the question: how do we take existing classroom spaces and small/shrinking budgets and make the spaces work well for the teaching of writing? Based on financial comparisons of equipment between the flexible classroom versus classrooms where computers are provided by the university, as well as student surveys, the authors found that a flexible design is a cost-effective solution that is also an effective pedagogical space.     

邳州市农村饮用水安全信息化建设方案研究

农村饮水安全保障是脱贫攻坚目标的重要内容之一,农村饮用水安全工程是一项惠及广大群众的民生工程。为加强农村饮用水安全工程运行管理,有效保障民生用水安全,邳州市水务局开展农村饮用水安全信息化建设,在充分研究当地农村饮用水现状基础上,提出邳州市农村饮用水安全信息化建设方案,采用一体化设计思路,分区分层确保用水信息安全,开发泵站监控、水量水质监测、管网运行监视、水费计收等业务应用功能,建立科学高效的水安全管理信息系统,提高管理水平,达到农村饮用水安全工程水量自动控制、水质有效保障、水费精确收取等目标要求,为保障农村居民饮用水安全提供决策支持。     

Mars Pathfinder Microrover

When the Mars Pathfinder (MPF) spacecraft lands on Mars, the Microrover Flight Experiment (MFEX) will be deployed and perform its mission to conduct technology experiments verifying the engineering design, to deploy an alpha proton x-ray spectrometer (APXS) to measure elemental properties of rocks and soil, and to image the MPF lander. In accomplishing this mission the MFEX rover must determine a safe path to goal locations traversing over a poorly known Martian surface. The rover does this mission with a capable mobile platform executing on-board autonomous functions of navigation and hazard avoidance. In this paper we describe the rover, its operational environment and the implementation of the on-board autonomous functions.     

水资源应急管理系统建设思路研究＊

基于国家水资源监控管理能力建设对突发水资源灾害事件的管理目标,结合现代计算机技术,开展水资源突发事件业务研究,进行水资源应急管理业务系统设计与开发,梳理形成一套具有一定通用性的水资源应急管理基本业务流程,并研发形成一个水资源应急管理系统软件。实例模拟处置应用表明,本研究成果具备复杂环境下水资源应急处置信息的组织与分析能力,基本适用于水资源应急管理。     

Review: The Benefits and Applications of Bioinspired Flight Capabilities

This paper addresses the challenges of flight on Mars that at this time have the same element of novelty as flight on Earth itself was a novelty in the Kitty Hawk era almost 100 years ago, details the scientific need for such flyers, highlights the bioinspired engineering of exploration systems (BEES) flyer development and finally describes a few viable mission architecture options that allow reliable data return from the BEES flyers using the limited telecom infrastructure that can be made available with a lander base to orbiter combination on Mars. Our recent developments using inspiration from biology that are enabling the pathway to demonstrate flight capability for Mars exploration are described. These developments hold substantial spin‐offs for a variety of applications both for NASA and DoD. Unmanned exploration to date suggests that Mars once had abundant liquid water (considered essential for life as we know it). It is not clear what transpired on the Martian climate to have turned the planet into the desert that it is today. Developing a comprehensive understanding of the past and present climatic events for Mars may provide important information relevant to the future of our own planet. Such exploration missions are enabled using the BEES technology. © 2003 Wiley Periodicals, Inc.     

Mars microrover navigation: Performance evaluation and enhancement

In 1996, NASA will launch the Mars Pathfinder spacecraft, which will carry an 11 kg rover to explore the immediate vicinity of the lander. To assess the capabilities of the rover, as well as to set priorities for future rover research, it is essential to evaluate the performance of its autonomous navigation system as a function of terrain characteristics. Unfortunately, very little of this kind of evaluation has been done, for either planetary rovers or terrestrial applications. To fill this gap, we have constructed a new microrover testbed consisting of the Rocky 3.2 vehicle and an indoor test arena with overhead cameras for automatic, real-time tracking of the true rover position and heading. We create Mars analog terrains in this arena by randomly distributing rocks according to an exponential model of Mars rock size frequency created from Viking lander imagery. To date, we have recorded detailed logs from over 85 navigation trials in this testbed. In this paper, we outline current plans for Mars exploration over the next decade, summarize the design of the lander and rover for the 1996 Pathfinder mission, and introduce a decomposition of rover navigation into four major functions: goal designation, rover localization, hazard detection, and path selection. We then describe the Pathfinder approach to each function, present results to date of evaluating the performance of each function, and outline our approach to enhancing performance for future missions. The results show key limitations in the quality of rover localization, the speed of hazard detection, and the ability of behavior control algorithms for path selection to negotiate the rock frequencies likely to be encountered on Mars. We believe that the facilities, methodologies, and to some extent the specific performance results presented here will provide valuable examples for efforts to evaluate robotic vehicle performance in other applications.     

STARS and stripes

The overall goal of DoD's Software Initiative is to meet DoD's future software needs by an order of magnitude improvement in the state of the practice, and to hasten the transition of new technology. The STARS Program (Software Technology for Adaptable, Reliable Systems) is one of the components of the Software Initiative. Other components are the Ada¹ Program and the Software Engineering Institute. The STARS Program is to result in a fully integrated environment which captures all phases of the software life cycle. From April 30 to May 2, 1985, the first DoD/Industry STARS Program Conference was organized, which brought together representatives of government, industry, and the academic community to review and discuss the STARS Program and other components of the Software Initiative. Below, we report on the presentations given at this conference.     

湖北省国家水资源监控能力建设项目运维管理机制探讨

通过介绍湖北水资源监控能力建设项目主要建设内容和运行维护对象,结合系统试运行期间暴露的问题,分析原因,从项目运维管理机制方面展开研究并提出策略,以期实现延长水资源监控能力建设项目生命周期的目标。