Advantages and Disadvantages of Aerial Surveying
What is Aerial Surveying? Advantages and Disadvantages of Aerial Surveying
What is Aerial Surveying?
Aerial surveying is a means of collecting geomatics or other imagery using airplanes, helicopters, unmanned airborne vehicles (UAVs), balloons, or other aerial methods.
Aerial photography, Lidar, remote sensing (using variously visible and invisible bands of the electromagnetic spectrum, such as infrared, gamma, or ultraviolet), and geophysical data (such as aeromagnetic surveys and gravity) are common forms of data obtained.
It can also refer to a chart or map created by flying over a region and analyzing it.
Because of its superior resolution, clarity, and atmospheric circumstances, aerial surveys should be distinguished from satellite imagery technology (which can negatively impact and obscure satellite observation).
Today, the aerial survey is frequently used interchangeably with aero photogrammetry, a type of photogrammetry in which the camera is mounted in the air. Photogrammetric technology and methodologies give measurements on aerial photographs.
Types of Aerial Surveying
The three types are:
Drone Photogrammetry
In high demand, drone photogrammetry is the use of the aerial camera to shoot a large number of images in one or more flight paths. From these pictures, an accurate 3D model can be created, which is the most efficient way to measure long distances and complex terrain.
Depending on the purpose, drone photogrammetry can be used for:
It can also benefit from other geospatial technologies such as LiDAR, GPS, IMU, and artificial intelligence (AI) for analysis, planning, and implementation.
Helicopter-mounted camera photogrammetry
Helicopter-mounted cameras are used to take aerial images of buildings, natural or man-made structures. The helicopter is flown over the area at an altitude of 150 meters to 500 meters.
These images are then used for property assessment, mapping, and other applications. Helicopter-mounted cameras are also called “pushbroom” because of their resemblance with a broom in their appearance.
The principal advantage of this system is its ability to cover a wide area in a relatively short time and with low altitude, which limits privacy concerns.
Helicopter-mounted cameras can be equipped with digital cameras or digital video cameras, or an integrated combination of both. The images are then used for property assessment, mapping and other applications.
Plane-mounted camera photogrammetry
For this type of aerial survey, a high-quality camera, and a high-resolution photographic film mounted on a fixed-wing aircraft are used. The plane is flown over the area at an altitude of 150 meters to 500 meters.
There are two principal advantages of this system: its ability to cover several areas in one flight, and its efficiency during long periods of time. The latter is made possible by the fact that planes can hold more film than a helicopter.
A plane-mounted camera is also called a “wing” because of its resemblance with a wing in its appearance.
Aerial Surveying Equipment
The most common are:
Total Station-
This is a total station, and this device is mounted in the plane at an angle of 45 degrees. A real-time image is used to monitor the area and the measurements are captured by the GPS coordinate. The camera captures a moment in time as it focuses on particular locations.
Drones-
A drone is an unmanned aircraft. A drone takes photographs and has the ability to fly to any location at any time. Drones are also used for surveys, photography, and mapping.
Cameras for drones are the most reliable in aerial surveying because they have the ability to capture a single image from different angles or from different altitudes without changing its flight path.
The camera is equipped with a wide-angle lens and operates in cloudy weather conditions. The camera captures a moment in time as it focuses on particular locations.
Stereoscope-
This is also known as a “lateral” system. There are two telescopes mounted to the plane at 45 degrees, these are both secured to the plane with industrial-grade velcro.
The image captured by one of the telescopes is projected onto the other, allowing it and 3D imaging. This system has a cost-saving when compared to the two alternative systems which use cameras on drones or fixed-wing aircraft.
GPD Devices-
This is a camera that uses digital photogrammetry devices. The GPD device is mounted on the plane complete with a glass plate film, which gives an instant capture of images. This device also has a GPS system that gives measurements every time there is a change in the image.
Helicopters-
Helicopters can be modified for aerial surveying by installing a total station or GPD device.
Helicopter-Photogrammetry can be carried out using a helicopter with a camera onboard. The aerial photography is performed from an altitude of 150 meters to 500 meters, which is about 10 to 15 times higher than the height of houses
Balloons-
Balloons are used to take high-altitude images from any location at particular locations.
Balloon-Photogrammetry can be carried out using a small balloon (1 meter in diameter) with a camera onboard, which is blown into the air by a parachute.
The great advantage of this type of aerial survey is the fact that it can be performed almost anywhere, regardless of accessibility.
The images are then used for property assessment, mapping, and other applications. This type of aerial survey is commonly used to observe several properties in a restricted area.
Plane-
Photogrammetry can be carried out using a small aircraft (20 seats). It is mostly used for observing large areas and taking high-quality photographs. It is also used to measure large areas.
Aerial Surveying Materials
Aerial photography must be done with care to prevent distortion of the image.
Today, there are many types of technologies to get aerial data. They can be categorized into:
- Surveying Camera Technology
- Optical Technology
- LiDAR Technology
Surveying Camera Technology
An aerial camera is most commonly used to measure or collect data from an aerial platform. This camera can be either hand-held, mounted on a pole, or attached to an unmanned aircraft system (UAS) depending on the purpose of the survey.
The camera and its methodology are distinct from aerial photography. The images gathered by these cameras are then used to produce a digital surface model (DSM), Digital Terrain Model (DTM), and contour maps, using photogrammetric methods.
Optical Technology
Both single and twin-engine planes equipped with video cameras provide both video and still images of an airborne scene at the same time. Low-altitude imagery captured using this method is referred to as lidar.
Lidar data can be collected by scanning an area with a laser beam, which is then reflected back to the plane’s sensors in pulses of light. The entire process takes a few minutes, and the data enables accurate high-resolution (down to 1 mm) mapping of the earth’s surface.
LiDAR Technology
A LiDAR is a laser-based data system that uses sound waves to measure the distance between points on the earth surface. In order to collect data, a LiDAR emits short pulses of laser light from its device.
Using measurements from the time it takes for the pulse of light to go through a particular point on the ground and return, measurements are taken with great precision. The height and direction of each point can then be calculated with great accuracy and map accuracy.
Aerial Surveying Uses
The uses include:
- Completing detailed surveys for building, transportation, and infrastructure
- Risk assessments
- Completing detailed surveys for building, transportation, and infrastructure
- Volumetric estimates for earthworks, heaps, and landfills
- Construction and site development monitoring
- Significant sporting occurrences
Aerial Surveying Applications
The applications include:
In GIS
In GIS-related applications, aerial photography is commonly used to create orthophotos. Orthophotos are two-dimensional pictures that can be used in land information systems to make pictures and maps that are geometrically accurate.
“This is because the images are first corrected by using a ground control point, which must be measured before they can be applied to the image.
In Land use planning
Land use planners may make an aerial survey of an area to determine the types of activities that are taking place. Surveyors will note any properties, buildings or roads in the area and make a record of any significant features.
They may also make a record of land use or zoning type. The photographs they take can be used to create maps showing any changes in the environment over time.
This is done by comparing aerial photos taken at different dates and noting changes against maps made for reference points in the surrounding area.
Land development
An aerial survey of an area is usually the first step in planning a new land development. The survey provides information essential for the layout of buildings and future roads and utilities.
Most often, a survey is made prior to construction to determine the cost of improvements. It is also possible to make use of an existing aerial survey when planning additional infrastructure.
An aerial photograph can be used to prepare a site plan that can then be converted into a detailed drawing or map by photogrammetry or map-making software.
Property assessment and appraisal
Land assessors and real estate appraisers may use aerial photography or other aerial data to measure the size of a property, record crops, examine land use, assess the condition of buildings and facilities, or record the area populated by any specified land use.
Aerial Surveying is not just a simple job. The imagery obtained through these surveys can be used for many purposes. The information gathered allows people to plan ahead, predict trends and make important decisions.
Transportation infrastructure and road mapping
Aerial photography is used for transportation projects to inspect locations for problems before construction begins. It can also be used to evaluate the condition of the existing transportation system, as well as possible upgrades.
Evaluating natural resource management
Ensuring that resource uses are in compliance with land management plans can be difficult and time consuming.
This is where aerial surveys can come into play. This is done by mapping the reserves of timber, soil, water and other resources available within a specific area.
Pipeline mapping, inspection, and maintenance
Aerial surveys are useful for detecting the locations of leaks and other damage in underground pipelines. This can be particularly useful in remote locations or those where access is limited.
Aerial survey crews use digital cameras to detect and record pipeline conditions, as well as changes over time.
Geological mapping
An aerial photograph can provide information about land formations, and is used to help them better understand the environment.
Aerial Surveying Safety Measures
Before any survey is made, safety precautions should be taken.
This includes;
- Ensure that the area to be surveyed has been given permission by the landowner and that there are no hazards lurking in the way
- When taking photographs of people or other moving subjects, make sure they are easily identifiable and that they are not wearing anything that could obscure them.
- Always keep an eye on your surroundings and remain vigilant at all times
- Make sure you have appropriate training before you conduct any surveys.
- Do not fly your plane except in clear weather conditions.
- Try to choose an aircraft with a crash-resistant design and high visibility markings to help avoid accidents
- Avoid flying in tight circles or loops, which could be fatal if you lose control.
- Do not try to take photographs while flying as this can be very dangerous
Advantages and Disadvantages of Aerial Surveying
Advantages Of Aerial Surveying
Aerial Surveying is one of the major techniques in Land survey.
The main advantage of aerial survey is that it provides a panoramic view of the area, which helps in accurate and faster measurements.
The methods used in the aerial surveys are well developed and are standardized by national and international standards.
It can be flown in any direction with the help of a GPS navigation system.
Another advantage is that it can provide high-resolution data with great accuracy compared to Total Station or GPS.
Aerial photography also allows the user to execute remote control, survey or survey data acquisition.
Disadvantages Of Aerial Surveying
- Aerial Surveying can also be prone to errors. There are a few reasons for which errors can occur.
These include;
- Instruments can have scale errors
- Climatic condition (Temperature and humidity changes in the atmosphere)
- Atmospheric turbulence
- Indoor measurements
- Aerial Survey is also unreliable in flatlands. It cannot be used in areas where the topography is flat, as aerial photography cannot capture objects smaller than the camera’s pixel size at a certain height above ground level.
- The Panoramic view of the area that the Aerial Survey gives is very attractive, but it can also be misleading and sometimes wrong.
- For an aerial survey to be accurate, it requires a good knowledge of photogrammetry or map-making skills.
- Machine errors can occur and mistakes can happen due to lack of experience of the personnel (measurer).
- There are certain ways that Aerial Survey can fail to properly measure the extent of land, it has limitation in measuring steep slopes since it does not have any ability to sense depth and no ability to level out the slope for continuous straight lines across the slope.
Aerial Surveying Faqs
What is aerial surveying?
Aerial surveying is the process of measuring, mapping, and monitoring various geographical points from an aircraft. Aerial surveying is also used to make maps and plans for land development projects.
What is the importance of aerial surveys?
Aerial surveys help land managers in making accurate and precise measurements instantly. It can also be used to map the area for different land use, such as agriculture, forestry or housing. Aerial surveys are also used for environmental protection.
What skills are required for aerial surveying?
Aerial surveying requires certain skills and knowledge that only a trained professional has access to. The professional should be at least 18 years of age to be able to carry out aerial survey work safely and properly.
How much does aerial surveying cost?
Aerial survey costs vary from one place to another depending on the type of aerial survey that is being carried out. But would always be significantly less than the cost of ground surveying.
When it comes to the occupation of a professional, it would only be through proper training and experience that a correct estimation can be determined.
Which instrument is used to study the aerial photographs?
A simple lens stereoscope or, if preferred, a mirror stereoscope with binocular attachment is all that is required for area reconnaissance using accessible aerial pictures.
How does aerial surveying work?
Aerial Surveying works on the principle of geodesy. The method used for it is something similar to that of Total Station and GPS devices.
This is a complicated system that has an aircraft and a satellite placed in orbit. Once the aircraft takes off, it gathers a series of photographs by flying in different directions at different altitudes.
The photographs are then examined and analyzed via computer to give exact measurements of all the features present in the pictures.
What are the benefits of aerial surveying?
Aerial Surveying is normally used to measure land measurement, carry out monitoring and provide data to computer.
Aerial Survey allows easy measurements of the physical features of land, such as slope, areas and length of roads. It is also used for topographical surveys to provide maps for different projects.
What are the advantages of aerial survey?
Aerial survey helps to identify resources and dangers on the ground. This is especially helpful for agricultural lands, as it will help determine if there are any areas where different kinds of crops can be grown.
It is also used extensively by the military and police to give them a bird’s eye view of a large area. The advantages of aerial survey are many.
What are the disadvantages of aerial surveying?
Usually, the benefits of aerial surveys outweigh the disadvantages but there is always a chance that there could be some, such as aircraft malfunction or elements that go wrong on ground. However, with modern instruments, these problems are minimized to a great extent.
How is aerial survey used for land development?
Aerial Survey is one of the most important tools used in land development and planning. It helps in making topographical maps, which are also required for proper planning and development of land. Land development is also required for housing, agriculture, and road construction.
What is aerial remote sensing?
Aerial Remote Sensing Photography has been defined as the science of taking an image from a satellite location for the goal of performing some type of study of the earth’s surface. Radar imaging is obtained by collecting and measuring the reflection of pulses transmitted by aircraft or satellites.
What aerial surveying is and what it does
Aerial surveying is the process of mapping an area using airborne images. Aerial surveying is used in a variety of applications, including land planning, real estate, infrastructure development, and environmental monitoring.
The benefits of aerial surveying include the ability to survey in high resolution and to detect and map any irregularities or errors in the ground.
The use of aerial surveys
Aerial surveys are used for a variety of purposes, including land planning, real estate, infrastructure development, and environmental monitoring.
The benefits of aerial surveying include the ability to survey in high resolution and to detect and map any irregularities or errors in the ground.
What are the benefits of Aerial Surveying?
Aerial surveying has many benefits that can help your business. For example, it can help you map an area quickly and accurately, allowing you to make better decisions about where to build or install a product.
Additionally, aerial surveying can help you determine the size of an area and identify any irregularities or errors in the ground.
By mapping an area using aerial imagery, you can improve your understanding of it and make better decisions about how to develop it.
What are some advantages of Aerial Surveying
Aerial surveying has a number of advantages, including the following:
– Aerial surveying is more accurate than ground surveys.
– Aerial surveys can detect and map any irregularities or errors in the ground, which gives you an accurate view of where potential problems are located.
– Aerial surveys are fast and easy to use, making it possible to survey large areas quickly.
– Aerial surveys can be used in a variety of applications, including land planning, real estate, infrastructure development, and environmental monitoring.
What are some applications of Aerial Surveying
Aerial surveying is used in a variety of applications, including land planning, real estate, infrastructure development, and environmental monitoring.
The benefits of aerial surveying include the ability to survey in high resolution and to detect and map any irregularities or errors in the ground.