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|A surveyor uses RTK GNSS to capture a point. Her field controller contains feature libraries defined using office software.|
Today's surveying office software handles massive datasets to perform complex tasks, and productivity is growing faster in the office than in the field. The difficult part is making it look easy.
In the mid-1980s, a New Hampshire civil engineer named Dave Arnold developed a series of routines to run inside a new software package named AutoCAD. Written using the LISP programming language, Arnold’s routines provided surveying and civil engineering functionality within AutoCAD’s graphic environment. His company, DCA Software (later renamed to Softdesk), brought graphical design and computation to the broad surveying market and enabled surveyors to move away from the command-driven packages that ran on mainframes or dedicated engineering workstations. In just a few years, Softdesk became the dominant developer of PC-based software for architecture, engineering and construction (AEC). Softdesk was acquired by Autodesk in 1997, and its products formed the core of Autodesk’s AEC offerings.
Around the same time (and on the other side of the continent), Steve Chou and a group of former Hewlett Packard engineers in Oregon developed a set of surveying computations to run on the venerable HP-41C calculator. The software soon moved to the HP-48, and then into the field, where the HP-48 connected directly to the emerging electronic surveying instruments known as total stations. The company, Tripod Data Systems, would become a leading provider of data collection software and hardware in the U.S.
Stories of startup companies like these repeated in North America and around the world, as software developers worked to take advantage of the steady advances in surveying and computing technology. And while geographic and professional differences were large, the objectives were similar and familiar: By utilizing software that combined positioning computations with information management, surveyors could increase their efficiency and provide more and better services to their clients. The effort to integrate survey operations in the field and office required intimate knowledge of the entire surveying process. Surveying equipment manufacturers rose to the call. Today, software plays an enabling role in modern surveying systems.
As the core component of a surveying system, software can be broken into three classes: embedded systems, field applications and office systems.
|Georeferenced images from a total station enable software to compute positions of inaccessible points.|
- Embedded Software. Often known as “firmware,” embedded software runs in an instrument to perform basic measurement and functionality. While the firmware is often invisible to the user, it is responsible for the complex operations that provide the raw data used by the other system components. For example, total station firmware handles the internal subsystems that combine to deliver angles (or directions) and distances, and GNSS receiver firmware manages the receiver electronics to track and collect satellite observables. In most survey-grade GNSS receivers, the built-in firmware also performs the computations needed to produce positions, including centimeter-level results using RTK and active networks.
- Field Applications. Typically running onboard an instrument or handheld computer, field applications are used to collect and manage data from the surveying instruments. They guide the operator through the process of collecting data and setting out points at specified locations. In the past, hardware constraints such as size, weight and battery life often resulted in limited functionality for field software. As field computing hardware increased in speed and power, the capability of field applications increased as well. Today, it’s not unusual to compile and adjust a traverse in the field, or to visualize survey points on a digital image of the project site.
- Office Software. Surveying office software has historically handled data management and quality control for field data. The software performs traverse computations, GNSS post processing and network adjustments. It also creates maps and CAD files based on the field data. In addition, some surveying packages are part of, or tied closely to, systems for engineering and design, GIS and cadastral management.
While it’s difficult to overstate the impact of technology in the field, much of the recent advancement in surveying comes from increased capability in the office. The growth in power and functionality of office applications is not a coincidence. Rather, it is the direct result of two seemingly unrelated trends: The increasing physical capacity of computing technology, and the need for surveyors to provide more sophisticated services to their clients.
For example, early office software used raw data from total stations to produce plane coordinates, generally in two dimensions with an elevation component (2D + 1D). But even the seemingly simple computation to reduce EDM-observed distances to horizontal must account for local geography and requirements for projections and coordinate systems. As GPS moved into the surveying mainstream, manufacturers provided specialized software to accompany their field equipment. Surveyors used the GPS software to scrub field data and process raw observables into 3D vectors. And after computing the GPS vectors, several steps remained to bring the results into the local coordinate system and produce information that could be used by engineers, designers or other surveyors. However, the early attempts to “do everything” in a single system were often lacking. GPS processing software often had no capability to handle terrestrial measurements, and the GPS field techniques did not lend themselves to collecting detailed linework and descriptors. Add to this the need to meet the needs of a global market, and developers of surveying systems faced a daunting task.
|Office software combines aerial images with surveyed points and design information. Customized reports and outputs deliver results to downstream stakeholders.|
Today, the positioning technology is mature, but still evolving. Thanks to modern software, the way in which an observation is presented to its end user is largely independent of the sensor used to collect it. Providing the best possible measurement systems is only part of the picture. The larger opportunity to provide new value to users lies in their ability to deliver complete solutions to their clients. Much of this work takes place on the surveyor’s desktop.
Moore’s Law, which is named after a co-founder of Intel Corp., predicts that the performance of computer chips and electronic devices improves at roughly exponential rates. This increase comes mainly from the ability to place more and faster components onto a chip while maintaining or reducing the chip’s cost. And while Intel is best known for microprocessors in desktop and portable computers, the effects of Moore’s Law on surveying first appeared in the field. Survey manufacturers worked to ensure that their core technologies--accurate measurement and delivery of positions--were productive. As a result, improvements in hardware (total stations, GNSS receivers and field data controllers) often received the headlines. But that’s only part of the story.
It turns out that much of the progress of the past two decades has come from programmers and software engineers. Certainly, fast hardware is important, but new approaches to processing and visualization come more from software science than chip designs. For example, new algorithms and filtering techniques have produced a tenfold improvement in GNSS processing. RTK initialization or baseline post-processing that once required several minutes (or more!) of GNSS observations can now be solved with just a few seconds of data.
Similar gains may be seen across the surveying discipline. For example, 3D scanning is opening a new arena of services that surveyors can provide. Just a few years ago, the volume of data generated by 3D scanners (and the new applications for the data) exceeded the capability of surveying office applications. As a result, 3D scanners came with their own field and office software, which often required additional training and dedicated staffing. Once the scanning data was processed, technicians needed to perform additional work to merge the scanning results with conventional or GNSS surveys.
These issues were solved through software engineering. Trimble incorporated survey functionality into 3D scanning operations, including the ability to incorporate total station or GNSS positions into the process of registering multiple scans into a single 3D dataset. From there, new technologies for modeling and feature extraction simplified and automated the work of creating the 3D objects and surfaces needed by downstream applications for engineering and design. The technician can incorporate data from GNSS and total stations to add additional value to the scanning process. This workflow is one that the surveyor can recognize immediately: Gather complete information, ensure that it is accurate and deliver it to the client in a form that can be used in the next stages of the project. The two general approaches to providing the software for this process are to combine functionalities from multiple sources or use a single-source solution.
|Survey measurements can be quickly refined to points, layers, symbols and linework.|
Some surveying industry manufacturers concentrate on providing sensors and field software to support the basic measurement functions. This concept relies on third-party software developers to carry the process into and through the office stages. By contrast, providing both field and office software that integrate systems for surveying, construction and other geospatial disciplines helps to ensure the highest level of functionality and communications, which enables field applications to take full advantage of the field instruments’ capabilities. At the same time, the field software can capture and record specialized information that enables the office software to conduct quality checks, analyses and transfer to downstream systems. For example, today’s GNSS systems can capture data on the tilt of the receiver pole. The office software uses that information as part of the quality control and reporting process.
To illustrate the importance of the integrated system, let’s consider GNSS baseline measurements. The firmware in the Trimble R10 GNSS receiver, for example, utilizes Trimble’s HD-GNSS method for RTK baseline computations. These same algorithms run in Trimble Business Center software for post- processed static and RTK infill computations. This helps ensure that results in the field are consistent with the positions that the same data produce in the office.
A second way to view productivity of the survey life cycle is to look at interfaces between professions and disciplines. Any time the data transfer is inefficient, the potential for data loss, error and costly rework increases tremendously. Thus, reducing and streamlining data transfers plays an important role in modern office applications. Integrated or single-source systems excel in this regard. Raw data can be uploaded from the field computer to a cloud-based or office server while the crew is still in the field. This information is immediately accessible to the office technician, who can check and plot the data from a location that may be far removed from the jobsite. Because field surveyors can quickly receive results and feedback, there are fewer errors in field coding, which translates directly to less time in office processing.
Perhaps the most important advancement in survey software comes in deliverables and visualization. For many people, a 3D image is a superb method of presenting survey data. Software for 3D scanning can provide views of point clouds or rendered models that are readily understood by people of varying technical levels. When combined with digital photos, the results are photorealistic 3D images of a site. Survey data exported into KML format can be connected to existing locations and viewed in Google Earth. And by using 3D modeling packages, such as Trimble SketchUp, surveyors and designers can quickly produce images and presentations to be shared across the continuum from the field to the office to the boardroom.
|RTK surveys on a construction site can easily merge with data from total stations or 3D scanners. Advanced software combines information from multiple sensors.|
While the integrated systems offer strong benefits, there’s always concern that unique needs may not be met. This challenge can be addressed by enabling users to create specialized applications running within the environment of the field or office software. Using software development kits and assistance from the manufacturer, surveyors and software developers can create customized routines and workflows specific to their needs. While this may seem like a throwback to Dave Arnold’s routines, today’s software development environments are far removed from the LISP language of the 1980s. In this, the benefits of the single-source system become apparent since developers can utilize existing, thoroughly tested routines that provide consistent user interfaces and outputs. By providing access to library functions such as interaction with instruments, common computations and report generation, the software development kits reduce the time needed to develop and test customized applications.
It’s an exciting and challenging enigma. On one hand, survey office software needs to support complex, rigorous processes and to document its results. It must also provide advanced users with control over computations to develop the best results based on their data. On the other hand, software needs to be simple to use, even automatic if possible. Many users want to set up the calculation process and walk away, leaving the software to handle the work on its own. And inexperienced operators may require additional guidance as they master a system’s interface and workflows.
An important example comes in the emergence of office-based photogrammetry. By using a total station equipped with Trimble VISION, a survey crew can collect digital site images. Each image is georeferenced and oriented with high precision and can be easily matched to adjoining images. Because the stationary, ground-based camera eliminates many of the variables commonly addressed in aerial photogrammetry, it provides nearly ideal input into the photogrammetric process. This has allowed Trimble to incorporate photogrammetric operations into survey office software. The office technician can use the images to collect points with survey precision, without a return visit to the field. And with the ability to combine photogrammetry into the normal field and office workflows, the potential for “office surveys” of difficult or complicated sites is looming large indeed.
Today’s applications integrate the work processes and data flow between surveyors and their clients, and do so in a manner more transparent than ever before. With its role in information management, processing and visualization, office software will continue to play a dominant role in surveying systems. And along with new measurement systems and faster computers, software algorithms and interfaces will become more sophisticated and efficient.
Yes, the technology in modern surveying systems is complex, and that’s impressive. But more important--and far more impressive--is how the complexity is contained within systems that are increasingly productive and easy to use. It’s a necessary--and exciting--part of the development that is bringing the field to the desktop with growing speed and clarity.
Software Updates: Unfinished Business
Many people view software as fluid. It changes often and never seems to be finished. Users frequently point out that there is always something to be added or done differently. But the fluid nature of a computer program is one of its biggest strengths. Fluidity allows a developer to keep its software current with industry trends in hardware and measurement, and to fill an ever-widening cross section of functionality and workflow needs.
A typical software update consists of dozens of changes to the program. Some changes may be quite visible and add considerable value to the software, while others are more subtle or specialized. In either case, virtually all changes originate with comments and requests from end users. That makes it important to read through the release notes for any new software version. It’s very likely that you’ll discover some new functions you may not have expected that will help make your work faster and easier. In addition to new functionality, regular upgrades enable a developer’s customers to keep pace with external factors such as changes in operating systems and computing hardware.
Like the professional and commercial grade software in most industries, developers of surveying software charge maintenance or upgrade fees for their products. Some packages operate on a subscription model, in which users pay an annual fee for the use of the software. In either the subscription or fee-based approach, it turns out that software maintenance is minimal when compared to other operational costs. One license (or “seat”) of software usually supports multiple field crews and accounts for a large portion of a firm’s surveying revenue. Yet the cost to maintain the firm’s surveying software is often lower than the cost to maintain just a single survey vehicle for the same year.
Software developers encourage their customers to keep their software up to date. Many surveying organizations plan for regular software updates and incorporate the fees into their operating budgets and schedules. They examine the new features to determine any need for additional training or changes to incorporate the new functionality into their work processes. Some developers provide videos and updated training materials to help users implement the new features. By controlling the rollout of new software into the firm, survey managers can optimize the benefits and ensure smooth transition to the new versions.