Photogrammetry Predicts Infrastructure Problems Before They Happen

Introduction

Inspecting any infrastructure asset like bridges, dams as well as massive skyscrapers is a vital task to their maintenance. Since these structures are huge, large, complex and often out of the way, the conventional methods like terrestrial LiDAR prove to be slow, expensive as well as challenging to use.

Let’s take an example of drinking water infrastructure inspection here which ran into some problem. The company was in need of a better way to inspect the infrastructure. Thus, they found what they were looking in for UAVs and photogrammetry technology.

With the use of photogrammetry technology, it was easy for the company to survey the dam with higher accuracy as compared to terrestrial LiDAR.

This not only gave higher coverage but also at much lower cost and with much smaller time as well.

With the use of UAV and Photogrammetry technology, the company was able to do a lot more regarding maintenance. Now they can make use of UAVs as well as photogrammetry to survey the dam regularly. They can also use preventative measures and repair the dam before any issues, thus saving money as well as lives involved in the overall process.

The Best Way To Maintain The Dam

A drinking water infrastructure is one of the crucial entities to maintain it with high safety standards. The company has also developed a model for predicting the dam response to the climatic changes including earthquakes as well as thermal variations.

Well, to feed this model, the company also requires exact data that can be gathered with short turnaround time. The UAV Photography can satisfy their needs, but the accuracy and precision requirements are still under the hood.

Any chance for Drone Photogrammetry?

Well, to achieve the target, the company set up an experiment to try it out. Firstly, they perform all the topographical surveys. With GPS, terrestrial laser scanners and aerial photography, the companies survey the main dam as well as supportive structures such as guard house and the weighing blocks.

Next step was to set up a UAV survey. Visualizing the atmospheric conditions, they began the study using Total stations to place control points around the dam and geolocate the results of the UAV photogrammetry. By sending the UAV, they were able to gather numerous photographs, around 6000.

After processing the photographs with Bentley’s Photogrammetry Software, the group generates both 3D model files and dense point clouds of the dam.

The company then compared the model files with the traditional survey data that was previously gathered.

Result? The UAV data enriched with data showing deviations within a range of 2 centimeters which was incredible!

Solution Of Issues Before They Arise

The dense point cloud generated by Photogrammetry software gave a good reflection of the reality. It was able to capture the current state of the dam within a short time. The point cloud data feed the model with accurate data that predicts changes in dam’s mechanical properties.

By using UAVs and Photogrammetry, it is now possible to perform proactive asset management. The tools and methodologies can detect the problems before they become real-world safety risks.

In simple words, with the use of Photogrammetry and UAV technologies, it is now possible to detect the issue before they arise and thus can save lives as well as money in the process.

Source: https://blog.nibt.education/2018/03/photogrammetry-predicts-infrastructure-problems/

Learn what is the Procedure of Photogrammetry

The photogrammetric procedure-

Project planning carries following steps:

• It Transforms project requirements to specifications concerning the area to be mapped imagined map scale and form interval. The purpose of these specifications depends on the necessary accuracy of the final map and cost constraints. More accurate maps are more expensive and take longer to collect it.
• Discover photogrammetric specifications concerning flight height, the number of images needed, the number of strips required, flight lines, estimated location for exposure sites, and equipment to use. Specifications must also develop for ground control, aerial triangulation, and compilation methodology.
• Develop a plan for aerial photography, fieldwork, and mapping compilation. The plan should coordinate with the several groups associated with the project. Crucial coordination is among the field team placing the targets and the aerial photography team. Goals should be set as close as possible to the time of photography. A project timetable with finish dates for different tasks and the estimated cost associated with them should develop as well.
• Determine the expected deliverables, including specifications on what features are to be mapped and their graphic representation.

Aerial Photography

 The steps aerial photography process consists are:

• Verification of the weather conditions that’s suitable for flying. Flying under conditions of low visibility or strong potential turbulence should be avoided. Bad climate conditions could produce not only unacceptable photographic effects but also risky for the flying crew.
• Mount the aerial camera according to the fixed procedure. Test the camera before using to ensure that it functions accurately.
• Fly the outlined routes and capture the photographs according to plans.
• Prepare the film according to specification to provide radiometrically and geometrically quality pictures.
• If required, print on the negatives the missing photo information (i.e., titles), like serial number, date, project information, etc.
• Prepare contact copies from the negatives. If needed, make enlargements that can use later, according to the requirements of the project.
• Inspect the pictures for image quality and coverage completeness. Confirm that each photograph has sufficient end laps to secure stereoscopic coverage of the whole project area. A comparable inspection should perform to confirm complete side lap coverage. Incomplete end and side lap coverage or the coverage gaps will void the complete aerial photography and need re-planning or re-flying. Another survey that should perform is recognizing the preset targets. Target inspection involves inspecting whether they are visible, appear in a stereo coverage and whether there are sufficient of them to assure reliable results. If any targets are dropping, or the whole project can’t target, points that can be recognized and surveyed on the ground should select and marked on paper copies. A copy of the prints and a summary of the chosen points should then submit to the surveying team for field measurements.
• Choose photographs that will be useful for data accumulation and develop diapositives for them.

Ground Control 

• Analyze project area for existing control. Existing control that can target and save time and money by avoiding unnecessary field surveys. Sometimes it is more cost effective to extend the aerial photography slightly exceeding the project area to combine existing control rather than to establish new control.
• Conduct field surveys as discussed above. Field surveys of selected points are necessary after the aerial photography gets completed.
• Compute and adjust the field data and establish coordinate values for the control points.
• Develop a report on the surveys and the results generated. Accuracy analysis of the results should also include in the report. The study should show the methodology applied to determine that the results are in agreement with the project’s specifications.

Aerial Triangulation

• Arrange the photographs as a continuous strip, or a block if the project includes more than one strip.
• Select and mark and draw points. Pass and tie points should mark and calculate on the paper prints.
• Mark false pass and tie points on the diapositives with a point transfer device. Points marked in stereo (tie points) should execute with utmost care.
• Measure and record pass and tie ends with a photogrammetric plotter (with digital workstations). At least an inner correction must perform before measuring pass so that image coordinates of these points can get obtained easily. Measure and mark ground control points. Ground control points get identified with the same stereo model setup.
• Compute and adjust the aerial triangulation measurements. Also check the results for possible analysis, marking, identification and control errors.
• Prepare a record of the aerial triangulation results. The record must include the photogrammetric base layout and also a diagram displaying the location and titles of all the points. The results of the computations and accuracy analysis of final adjustment concerning the project specifications should maintain in the document as well.

Stereo Compilation

The use of often CAD-based digital mapping software has analyzed the document preparation, editing and also fault checking of the stereo compilation process. The stereo compilation process is as follows:

• Select models for mapping. The selection should involve a layout of the areas for mapping from the stereo model. The operator should also instruct and focus on the limits of the stereo model for mapping.
• Fixed up the stereo models by performing interior and exterior adjustments.
• Compile the Planimetric points according to the project specifications. The specifications should also remain precise about what features are to mapped and their graphic representation concerning color, shape, symbol, and other attributes.
• Compile elevation points as contours or place elevation. Outlines should also compile according to the specified contour interval.
• Examine the map for completeness, compatibility, and also accuracy. The purpose of examining the map for completeness is to check that all the required features have mapped. Latest photogrammetric plotters have a capacity of superimposing the map on the graphic image so that both of them can inspect simultaneously with correct spatial registration. This inspection is necessary, primarily for features that are mapping from more than one stereo model.
• Edit the map and execute the required improvements.

Field Completion 

Photogrammetry can be useful for mapping only what is visible on the images. Thus, if essential features get covered by trees, human-made structures or abrupt topography, they can’t map it.

Hence, to map the missing features a field finish activity has to take place. The field completion phase of the project can use for accuracy testing of the map.

 Drafting

Drafting of photogrammetrically derived maps performs the task with CAD software. It consists the following:

• Sheet Layout
• Sheet Format
• Scale Change
• Edit and Final improvements

All of the above parameters should be part of the project specifications and should perform accordingly.

Quality Control

Here the final report on the quality and efficiency of the maps should also complete the submission of the final result. The report should examine the accuracy of the control, as described in the Ground control and also Aerial Triangulation. The procedure utilized to define the map’s spatial and also content efficiency should keep in the document as well. A statement, such as “this map matches the National Map Accuracy Standards” or “the project specifications,” is unacceptable. An actual test and analysis must complete any claim of efficiency or standard. The testing methodology applied and the decisions of its implementation must keep in the document in a final report.

Source: https://blog.nibt.education/2018/03/photogrammetry-procedure/

Aerial Photogrammetry vs. Terrestrial Photogrammetry – Understand the Contrast

Photogrammetry is the science and technique that blends photography and geometry. The principle is straightforward, yet it has a significant impact on contemporary architectural establishments.

What is the procedure of photogrammetry, you can check here–

We all know that photography generates 2D illustrations. The photogrammetry system produces 3D estimations of the object and surface from the 2D image/photograph.

If you read our previous blogs on photogrammetry, then you will know that Aerial and Terrestrial are two major varieties of photogrammetry.

Let’s understand each one by one-

Aerial photogrammetry

A machine, especially an aircraft (purposefully designed plane) or a drone, i.e. Unmanned Aerial Vehicle (UAV) has the cameras attached. Therefore, it can capture photos from the higher surface. The larger the number of images, the higher is the accuracy of the statistics. It further helps in comparison of the quality.

The planes fly over the planned area with particular landmarks which they have to capture. The speed of the aircraft regulates the camera’s catching speed. Also, they know the height of the plane from the land surface. The photographed surface area’s base contour/boundary is drawn using Stereo Plotters.

Terrestrial photogrammetry

The word Terrestrial means relating to Earth. Therefore it explains that why the camera is in the stationary position in this kind of photogrammetry. The camera’s position is elevated, and the tilt angle, the focal length of the lens is adjusted.

Read More on Why Aerial Photogrammetry Differs from the Terrestrial One.

The main difference is between the working and methodologies, even though both are the branches of the photogrammetry.

Therefore, the outputs generated are very varied from each other.

Apprehend the following points to notice the distinction-

• The technical requirements of the Aerial photogrammetry are very high-end; the specially designed planes or drones are just the initials.
• Although there is a much lesser investment in Terrestrial photogrammetry, there is the requirement of high technical skills for operating the tools.
• To map a large surface area of the land, we can use Aerial photogrammetry. But the knowledge of longitudes and latitudes with their calculations are essential in photogrammetry operation.
• When there is a need for designers and planners to manage and plan bridges, transportation network, pipeline networks, etc. then Terrestrial photogrammetry is preferred. The adjustments of the camera’s axis as per the surface area matter a lot.
• The environmental projects which trace the changes of glaciers, volcanoes, earthquakes, etc., use terrestrial photogrammetry methods.
• The fixed location of the camera creates such kind of data sets to work upon further.
• There are various benefits of aerial photogrammetry in the security field as well. Archaeology also gets numerous advantages through aerial photogrammetry as you can see a big chunk of the area at once.
• Terrestrial photogrammetry is preferable for movement-related and comparatively smaller land masses, unlike the aerial one.
• The arena where both the fields play an active role is Urban Planning! That’s obvious as with the help of aerial photogrammetry, designers and planners generate an accurate perspective plan of the site or location. An aerial view gives a bright idea of all around the neighborhood, and so it helps in further assessment.
• Terrestrial photogrammetry, unlike aerial, creates visuals showing interrelation between civil constructions, safety issues, disaster management and various other problems. Thus, it helps in knowing the creation, prevention, and demolition of any civilization.

Final Derivation

Thus, it’s evident that by using both sorts of photogrammetry, we can generate most efficient and disaster-prone constructions/infrastructures.

So these were the fundamental differences between aerial and terrestrial photogrammetry. Have you had a clear insight?

Do write your views in the comments.

Source: https://blog.nibt.education/2018/03/difference-between-aerial-and-terrestrial-photogrammetry/

Why Choose Photogrammetry: A Summary for Everyone

Basic Definition of Photogrammetry

The basic definition of photogrammetry is the art, science, and technology of gathering reliable information regarding any physical object and the complete environment.  This technique involves a process of record-keeping, measuring, and evaluating terrestrial and aerial photographs.

Break-down of the term

In a sense, the breakdown of the term photogrammetry is in three parts: ‘photo’ – meaning ‘picture,’ ‘gram’ – meaning ‘drawing’ and ‘metry’ – meaning ‘measurement.’

This explanation makes your understanding clear.

Early advancements in the system and science of photogrammetry happened many years before the actual invention of appropriate things to apply the application.  As time rolled on, the theories became a certainty, and the essential technologies came into existence.  The timing when all these things evolved was a crucial time.

The scope of photogrammetry

Photogrammetry is one of the most extensively and technically preferred means for producing maps. Significant development originated in European nations and later spread over into Canada and the U.S. In the early 1900’s, an International Society came into the formation for serving as a collaborative and collective house for the progress of this science. The fields of Remote sensing and Photogrammetry widened their horizons in recent years. As per consideration, to include the investigation of diversified media, the images are still the primary root of information.

Branches

There are two distinct branches when it comes to the application of photogrammetry.

The primary department requires precise estimations and calculations regarding the shape, size, and position of graphics features.

The second branch deals just with identification and description of the detailed features.

In both the cases, a specially designed accurate camera system takes the pictures.  The camera, therefore, is the source of all capturing of data and plays a vital role in any relevance.  The photo calculating devices, as well as the final system of output and interpretation, also are the significant areas of concern.  These three tools; camera, a mapping device, and production medium, will eventually define the status and application of photogrammetric measurements.

Why is photogrammetry so useful?

Notably, there are several reasons.  Since photography is primarily of the ‘non-contact’ category, it presents a different way of perceiving and documenting information, without the necessity of a physical appearance.  This statement holds true in the state of aerial photogrammetry.  Aerial cameras provide the facility to photograph difficult, hostile or dangerous matter, with scarce or no risk to material and group.  You can consider military functions as an example of this situation out of many others like it.

Additionally, there are numerous advantages of aerial photogrammetry applied widely in the nonmilitary application as well.  Like, Engineers, Designers, and Planners also use mapping and pictures.  Therefore, the resulting list represents these applications:

• Natural disaster
• Environmental studies
• Land use and planning
• Construction
• Site development
• Insurance studies
• Real estate
• Surveying
• Mineral and Geotechnical research
• Agricultural forecasting
• Civil engineering

Within the streams of nearly all services, there is a demand for specific mapping remarkably.  With the opening of technology, the usefulness of photogrammetry in above-mentioned and other areas is almost limitless.  Also, mappings, as well as other techniques, play an advanced role in satisfying the public desires for comfort, transportation, and ease.

Conclusion

You need to know the importance of such fields which are not into the limelight but give tremendous opportunities to work. Think out of the box for your career.

How is Photogrammetry useful in GIS (Geographic Information Systems)

Geographic Information System (GIS)

Geographic Information System is the one in which geographic information shared and displayed using GIS application tools. The GIS application tools help the users in analyzing the spatial data, edit data in maps, and make a presentation of the operations carried out in applications. GIS has got applications for different fields like engineering, planning, management, transport and logistics, insurance, telecommunication, and business sector.

Photogrammetry

Photogrammetry is carrying out measurements with the aid of pictures, particularly for the precise location of surface points. Found somewhere in the middle of the 19th century, photogrammetry is an age-old technology as of regular photography. The gap between 2 points lying on a plane which is in parallelism with the plane of the image, may be found by measurement of their distance on the image if the size of the image is understood.

Photogrammetry can be split into three different words as:

Photo – Light

Gram – Drawing

Metry – Measurement

So, photogrammetry is the process carried out consisting of lights, drawings, and measurements. The technology is implemented for creating maps. These maps are designed using drone cameras, and hence it is known as aerial photogrammetry.

One who is familiar with photogrammetry can work in sectors private organizations, government sector, agricultural sector, advertising organizations, environmental and medical sectors.

Photogrammetry finds application in the fields below:

• Topographic Mapping
• Architecture
• Engineering
• Manufacturing
• Quality Control
• Crime Investigation
• Geology
• Archeology
• Meteorology
• Film Industry
• Gaming
• Automobile Sector
• Analysis of Accidents
• Transportation
• Logistics

Consider an optical lens as a middle of the read and light-weight rays piercing straightly into the image through the center. If the standardization of the camera is correct, i.e., we all know the focal distance, then we can analyze the angles of the rays from entirely different points. Though we’ve got three points within the state of affairs and their 3D coordinates, then determinant the position of the middle gets simple. Further, the orientation of the exposure holds the importance. Instead, we can accurately establish a location exploitation GPS from fundamental knowledge.

When a square measures two overlapping pictures, there’s associate choice to come across the 3D vectors from each image. Further, we can outline the 3D location of points within the state of affairs.  Our brain performs this calculation of intersection once observing a 3D film or stereo. Even in computer’s vision, two pictures square measure combined to supply higher results.

Conclusion:

The modern technology needs a supportive system for mapping purposes. With the advent of new technologies, photogrammetry is proving to be useful for almost all the fields of work and its importance is growing nowadays. Photogrammetry is hence fulfilling public demands very effectively.

Do leave your views in the comment box below.

 Source: https://blog.nibt.education/2018/03/photogrammetry-usage-in-gis/

Top Three Reasons For Studying Photogrammetry

Introduction

Photogrammetry is one of the trending career options in today’s developing world. Graduates from any stream can do the photogrammetry course and opt for a better career opportunity. With the advancements in technologies, learning new things and adopting them inevitably leads to a better career. Thus, learning photogrammetry will open multiple career options to choose.

Let us overview best three reasons for studying photogrammetry that can lead to a better careerahead.

What is photogrammetry?

Photogrammetry is the combination of Photographs + Geometry.

Thus, if your interest lies in Photography and if you possess a good understanding of geometry, then photogrammetry is the best option for you.

Understanding the key concepts of maps, generating or creating the maps with the help of information gathered by using aerial vehicles is learned in Photogrammetry. Sounds interesting!

The top reasons for studying photogrammetry

Photogrammetry is essential and useful course because:

1. Photogrammetry is the science of 3D model generation which explores various aspects of math’s, geometry, photography and other software’s.

As a result, you can pick up more skills and learn many new things useful in future for you.

2. Earlier photogrammetry was limited to architectural surveys, but now, with the introduction of drones and 3D Printers in construction as well as video games, the application possibilities of using photogrammetry have grown tremendously. The industry is evolving at a very high speed. Once AR/VR become mainstream, Photogrammetry will undoubtedly take off, and the people with those skills will have a decent demand in the industry.

Hence, to reap a good career, you have to sow a seed of learning photogrammetry right now.

3. Learning photogrammetry is an exciting topic. It makes its students think in 3 Dimensional way. Isn’t that interesting?

The online world has developed in many aspects than the real world as soon as technology made it possible to do. The monochrome computer screens now are filled with color just like the real world. Then, there were pictures and images as well as the sound of our online experience just as we have it in our physical world.

The next wave is 3D wherein the user interfaces designs will have depth. For instance, think of logos of IBM and Coca-Cola having a three dimension look, won’t that look better?. Well, to learn this you should have the knowledge and understanding about photogrammetry.

Conclusion

Thus, to sustain in this ever-emerging technological world, there is always an interest and urge of learning new things, new technologies like Photogrammetry that undoubtedly will lead to a better career in future.

Source: https://blog.nibt.education/2018/03/studying-photogrammetry/

The need to understand the importance of the career in photogrammetry

Photogrammetry is one such field which is emerging at a higher rate, and there are a satisfying amount of reasons on why you should choose it as your career!

This blog intends to guide you through your questions like why learn photogrammetry, why photogrammetry is beneficial, what career opportunities are there in photogrammetry, etc.

First of all, you need to know what photogrammetry is, how it works, and what are its areas and applications in the various industries.

After knowing these things which I feel that those blogs hopefully guided you well, now it is the turn to tell after all why photogrammetry is beneficial for your career and why you should choose it?

The summary of the photogrammetry and the other blogs would have given quite a big idea on why photogrammetrists are in constant demand!

But here, we will discuss the top five reasons for why photogrammetry is beneficial for your career?

1. Take the road less traveled by

People, especially in India are least interested in experiments! Whenever we ask the question of career, precisely what to do after 12th, then all we know is Engineering/Medical/Government Exams of different sectors!

WHY? Why not we choose any other options? There are so many in which you can work in your areas of interest, without getting bored! The career areas in the field of Geographic Information Systems give you an ocean of opportunities and jobs! These jobs also guarantee you the success which you desire. Jobs in photogrammetry are the recent trend and will continue to give you multiple benefits.

2. Several opportunities and uses but lack of skill

The private sector survey done in the ASPRS/NASA’s managers revealed that there is a shortage of trained workers. The lack of the necessary skill sets among a significant number of the graduates creates too many vacancies. With few exceptions like National Institute of Building Technology, only the more prominent universities offer programs like remote sensing and photogrammetry. The massive cost of the technology and a deficiency of expertise makes this course as a rare gem in India. In the hope to raise the professional bar, colleges, universities, and institutions are starting to offer further GIS/ remote sensing related programs and hiring expert faculty.

3. Umpteen industries to work in

Photogrammetry helps in solving complex human-made world issues and touching all aspects of life. The role of Photogrammetry is becoming more and more critical for the precise decision-making process. Practical knowledge is very crucial to understand the concept deeply to explore the innovative use of the technology and its application areas. The broad range of applications amplifies the jobs in photogrammetry all over the globe. You can find jobs in photogrammetry anywhere in the world in the varied number of fields! The areas and applications can be seen here.

4. Immortal field

Jobs in photogrammetry and cartography are projected to grow 30 percent from 2017 to 2025, faster than the combined average for all occupations!

Overall, photogrammetrists and cartographers are likely to be in demand for ensuring the authenticity and precision of future maps.

Also, growing use of maps for national defense and local government preparation will fuel employment rise. The widening use of mobile, GPS, GPRS and multiple technologies will also result in current jobs for photogrammetrists and cartographers.

Photogrammetrists, mainly, are in need to manage the satellite, aerial, and light-imaging detection and ranging (LIDAR) images.

Cartographers visualize spatial data and design the concluding presentation of information for customers. Their perfect design skills make data more accessible to users.

Photogrammetrists have excellent job opportunities. As there is a significant boost in the quantity of available mapping data, therefore, exists a need for photogrammetrists to refine and interpret this data. These workers will also be required to calibrate cameras and other tools when collecting this data.

5. Jobs will keep growing

The central fact and advantage of this area are that graduates, of whatever level of qualification, can usually land a job as soon as they complete their course. They will be getting a job when they will do a proper internship program. So, which fields you are planning to discover?

The GIS industry is enormous and shouting out for recruits. It is in the rare position where there are more jobs than the graduates! There are chances that you will work for offshore companies as well as for local authorities. They are always searching for people having GIS experience. Also, the transport companies, medical, environment, film and gaming industry, police services, agriculture, and numerous other industries desperately need photogrammetrists and GIS experts.

You can have rewarding jobs in this industry. Also, they surely have high chances to travel, and usually where their company pays the bills!

And then, there are multiple opportunities in academics and research too, if you find the career more appealing.

So, these were the solid top five reasons for doing jobs in photogrammetry! Now, if anyone asks you why you chose photogrammetry as a career, then you have five reasons to tell.

What are your plans for your career? Choose Photogrammetry and Never Look Back!

Learn UAV In Photogrammetry & Transformation Of Aerial Photogrammetry

Introduction to what is UAV?

UAV stands for Unman Aerial vehicle. It is the technology used in Photogrammetry tech for obtaining 4D images for mapping. UAV (unmanned aircraft/aerial vehicle) system creates 4D mapping outputs and 3D landscape models or photographs. The UAV Photogrammetry in future will play a vital role in the emergency rescue, rehabilitation or reconstruction, new or rural construction, development of digital cities or Smart cities, monitoring of geographic situations, AEC industry and multiple other areas.

UAV Photogrammetry is the technology that can also be universally used.

The areas where the UAV techniques imply:-

Environmental protection, mineral resources exploration, marine environment monitoring, land use investigation, water resources development, crop growth monitoring and yield estimation. Also in agricultural operations, natural disaster monitoring, and assessment. City planning and municipal management, forest pest and International Journal of Control. Also including Automation disease protection and monitoring, public safety, national defense, digital earth and advertising photography, etc. are also the sectors where the use of technology exists. The UAV Photogrammetry has a huge demand in the market.

Explore How UAVs have modified Aerial Photogrammetry

UAVs have recently grown broadly accessible to the business and commercial public. It is because UAVs before were used in military applications. UAV technology has entirely transformed the use of Photogrammetry in surveying because unlike aircraft or planes, they technically improve the technology’s essential strengths.

For beginners, the UAVs are easily available at low-cost. The availability of the UAV Photogrammetry has not only boosted the demand & popularity of Photogrammetry for surveying but also has built a unique market called as micro-mapping. Thus, it includes the topography or surveying of places shorter than 5 square kilometers.

Mainly, as the surveying had to do with manned aircraft, the projects or plans like these have been unprofitable or expensive. The high mobilization expenses and long projects deadlines made it challenging for conventional surveying firms to accept these jobs. However, UAVs that matches smoothly into a surveyor’s vehicle, operators can mobilize more rapidly. And can also develop these small projects in one day.

Furthermore, UAV Photogrammetry is versatile as compared to planes. As it comes to positioning, stages of elevation, and steering tight spaces. Thus it makes suitable for an extensive variety of jobs.

Examples- To solve the above obstacle, you can make use of drones. Several UAVs can also programme by using the unique flight path called “Waypoint.”. The drone’s waypoint technology allows it to pass accurately through tight areas which may be impossible for a human pilot to navigate in such areas. Thus, along with the drone’s dense size, that enables it to capture images under the tree awnings and other obstacles with ease.

Conclusion

In some regions, due to low elevation UAV Photogrammetry is with the procedure, fast, economical and other advantages. While a digital camera can modify and adjust the sensitivity of the ISO by changing the aperture, shutter, and fog on color, contrast, the brightness of the software. Thus it makes possible to capture a color image in the dark, cloudy or mist day. It is easy to get 4D mapping outputs with the help of full digital photogrammetric workstation. Low altitude UAV digital aerial photograph is an essential content of the actual-time data information system.

Mapping technology in access system is an excellent complement to existing aerospace aeronautics, image acquisition system. The primary means to deal with emergency surveying and mapping serviceis the necessary tool for critical areas of geographic monitoring conditions. It is a significant way to fast update of geographic information. With the constant growth of sensor technology, UAV Photogrammetry technology, communication technology and continuous growth of data processing software, UAV Aerial Photogrammetry system will more universally use on large-scale topographic mapping areas.

Source: https://blog.nibt.education/2018/03/uav-transformation-of-aerial-photogrammetry/

Photogrammetry: A New Trend in Site Surveying Technologies

How is the technology changing the construction industry more than ever before?

The digital construction is not just a concept anymore. With the onset of latest construction technologies, the industry is witnessing the evolution to a greater extent. The construction companies are now using more and more new techniques for better efficiency, productivity, and cost control on the projects. For instance, the perks of using drones for 3D mapping and photogrammetry in construction no longer needs any introduction.

The experts from various fields are acknowledging the benefits of using Photogrammetry for site surveying.  A renowned VDC Consultant Viet T.P Pham of MT Hojgaard in Denmark and Regional VDC Manager Blake Potts of Rogers-O’Brien Construction in the USA shared their insights on the current challenges the construction industry is facing and how the use of modern technologies will impact both onsite and off-site.

What are the challenges faced in construction nowadays?

Viet Pham – The most significant challenge in the construction sector is productivity, we can say lack of quality delivery or outcome. It is caused by multiple things including, lack of common goals, late involvement in the project, incorrect prerequisites for contractors or designers, lack of project materials or inconsistent coordination & communication.

Blake Potts – The Coordination of construction documents is a big challenge in the current construction industry. The design, as well as the construction schedules, are getting shorter and shorter. It means, we have to start learning from the beginning and to a deeper level than ever before. The questions and clarification which we ask during the design phase now have to be requested in advance.

Is the modern technology an unavoidable scenario of the present construction industry?

Viet Pham – well, if you go to construction sites, there seems no change in the past 50 years. The 2D drawings are still in use, resulting in errors and numerous issues thus, delaying the schedule. The upcoming technologies can change a lot.

With the use of simple tools, apps, the data sharing is convenient. The use of drones can capture, track and inspect the remote areas. The integrated 5D models can provide an overview of project sequence and monitor the cost throughout the project lifecycle.

Blake Potts – Absolutely! Technology can change tremendously in this regard.

Latest Trends in Site Surveying Technologies

Viet Pham – Photogrammetry is something that will undoubtedly change the way we survey. It is capable of rapidly cutting down on time and the cost it takes to generate the results.

Blake Potts – Photogrammetry is the newest technology which is enabling us to quickly gather as-built data from our job-sites that can further use in surveying data. The exciting thing is that the data collection can be done quickly in an automated fashion and, thus a considerable time saver for the team.

These are few insights of photogrammetry from the two renowned personals of the construction sector.

You can check the link  for more information:

What do you think? Does Photogrammetry turn out to be the best technology for site-surveying? Let us know in comments about your views on the use of Photogrammetry in site-surveying technologies.

Source : https://blog.nibt.education/2018/03/photogrammetry-new-trend-in-site-surveying-technologies/

Working of Photogrammetry and Remote Sensing

Clarification of the term- Photogrammetry

Photogrammetry, as the name suggests, is a 3-dimensional co-ordinate calculating technique. It uses images as the primary medium for metrology. The unrevealed principle used in photogrammetry is triangulation or more accurately called Aerial Triangulation. By taking at least two pictures from the so-called “lines of sight” get developed from the particular camera. They later become points on the object. To produce 3-dimensional co-ordinate plan of the points of interest, they mathematically intersect these lines of sight (which are of optical nature).

The Prussian architect Albrecht Meydenbauer in 1867 coined the term photogrammetry.

He fashioned some of the earliest topographic maps and elevation drawings. Photogrammetry services in topographic mapping are famous, but in recent years the technique has widely grown in the several fields. Various industries like engineering, architecture, underwater, forensic, geology, medicine, movies, games, and many other areas require precise 3D data.

Branches of photogrammetry

There are two broad-based categories in photogrammetry:

• Metric Photogrammetry: It comprises of the specific measurements and calculations on photographs about the size, shape, and position of graphics features. For obtaining other data such as relevant locations (co-ordinate) of areas, features, and volumes, these calculations are mandatory.
  The particular technical camera takes the photographs, and that camera gets used in engineering fields like surveying.

• Interpretive Photogrammetry: This type deals with perception and identification of the particular features on a photograph such as its size, shape, shadow, texture, pattern, etc. This type interprets the image to add importance and intelligence.

Remote Sensing

Remote Sensing technology is an essential part of photogrammetry. It also collects data from images. The term comes from the fact that you don't need to physically go to the place from where you want the data.

So, then what's the difference between remote sensing and photogrammetry?

The difference lies in the final information which we get. The colors specify the differences. Therefore, land use/land cover is one of the primary outputs of remote sensing process. The origin of remote sensing was to exploit a vast number of color zones in satellite images and to create 2D data primarily for GIS.

Nowadays, remote sensing devices are advanced which assist in 2D data gathering and formulation. Software tools today have a vaster and comprehensive range of technologies such as image mosaicing, 3D visualization, RADAR, GIS, as well as the softcopy photogrammetry.

Concepts to focus:

• Radiometric resolution.
• Spatial resolution.
• Temporal resolution
• Spectral resolution.
• The radiometric resolution represents the capacity of the sensor to estimate the brightness of objects or the signal strength (acoustic reflectance). The sensor which is more sensitive to the reflectance of an object than its surroundings will be beneficial to sense the smallest object.
• The spatial resolution represents the capacity of a sensor to identify the smallest dimension of a design on an image. In a sense, the separable distance between different patterns or things in a photograph which we can see in meters.
• The temporal resolution relies on many factors– what time a satellite will take to return to the approximately same location in space. Or, the area of the sensor (associated to its ‘footprint’), and whether the sensor can set can off-bottom. You can more formally call it as the ‘revisit period.’
• The spectral resolution uses the sensitivity of a sensor to give the response to a particular frequency spectrum (commonly for airborne and satellite sensors). The frequency scales include visible light, invisible light and also electromagnetic waves. The different wavelengths reflected from the objects (as different colors) make it possible to see the features. But, they must be adequately reflected.

I hope that you now understood the difference between photogrammetry and remote sensing from the above explanation.

Basis of photogrammetry

The basis of photogrammetry is perspective geometry. At the easiest level, you can consider a camera lens as a center of the view and light rays piercing straightly into the image through the center. If the calibration of the camera is proper, i.e., if we know the focal length, then we can analyze the angles of the rays from different points. Even if we have 3 points in the scenario and their 3D coordinates, then determining the position of the center gets easy. Further, the orientation of the photo holds the importance. Alternatively, we can accurately identify a location using GPS from initial data.

Knowing the orientation and position of the image enables us to determine the 3D vector from the image point. The center defines it per light ray.

When there are more than two overlapping images, there is an option to intersect the 3D vectors from every image. Further, we can define the 3D location of points in the scenario.  Our brains perform this calculation of intersection when watching a 3D movie or stereo pair. Even in computer's vision, more than two images are combined to produce better results.

Hence, this article was all about the working of photogrammetry and remote sensing.

Let us know your comments.

Source: https://blog.nibt.education/2018/03/working-of-photogrammetry-and-remote-sensing/