Difference between drone surveying and manual land surveying.
Surveying is a means of making relatively large-scale, accurate measurements of the Earth’s surfaces.
Land Survey involves the scientific process of measuring the dimensions of a particular area of the earth’s surface, including its horizontal distances, directions, angles, and elevations. Artificial structures, such as a road or building, may also be noted during a survey.
A Drone Survey refers to the use of a drone, or unmanned aerial vehicle (UAV), to capture aerial data with downward-facing sensors, such as RGB or multispectral cameras, and LIDAR payloads.
What are the Differences?
DRONE SURVEYING
Capturing topographic data with a drone is up to five times faster than with land-based methods and requires less manpower. With PPK geo-tagging, you also save time, as placing numerous GCPs is no longer necessary. You ultimately deliver your survey results faster and at a lower cost.
Drone maps created using good quality drone equipment, careful flight planning, commercial grade GPS ground control points and commercial grade processing software can potentially be accurate to around 2-3cm horizontally and around 5-6cm vertically.
Compared to other surveying methods, drone surveys can be completed in less time, as drones are able to cover large areas of land within a short period.
Typically, drone surveys can produce high-quality photographs and video recordings in a couple of hours.
TRADITIONAL LAND SURVEYING
While drones are agile and reliable, they can’t deal well with high winds. Drones are lightweight and small; high winds can blow them off course and make it impossible for them to get consistent readings. This is unlike traditional Land surveying equipment and instruments which are tethered to the ground.
The brick-size batteries used by drones are heavy and can get used up quickly unlike total stations which have better battery capacity. Although “the newer the model, the stronger the battery” according to Our In-house GIS Analyst, Mr Boluwatife Williams.
Traditional methods involve staff manually traversing a site to collect data points, whereas drones can collect this data with staff far away from potentially dangerous areas.
Manual surveying methods are incredibly accurate, the accuracy of the drone surveying is only threatened if the pilot is a greenhorn.
Surveying equipment is used under the most stressful conditions. They are exposed to extreme weather conditions, used in dusty construction areas and subject to bumpy transportation.
Adequate care and maintenance of the equipment, proper storage and good transportation are major factors in the successful completion of a survey.
Lack of good maintenance practices not only causes unjustified replacement costs but also can seriously affect the efficiency and accuracy of the equipment and the entire survey.
The list of surveying equipment includes:
Theodolites
Measuring Tape
Level and Rod
3D Scanners
Total stations
GPS/GNSS
Electronic measuring devices
GPS receivers and more.
These surveying instruments are designed to provide years of reliable use. The shafts, spindles, pendulums, and electronics of precision instruments, although constructed for rugged field conditions, can be easily damaged by careless acts, mishandling and continued negation of prescribed procedures for the use and care of the instrument.
Each new instrument is furnished with an operator’s manual. The manual contains a description of the instrument, specifications of its various components and capabilities, and applications. The manual also contains basic instructions for use of the instrument and describes recommended servicing and adjusting methods. The operator’s manual should be kept with the instrument at all times. Each operator should thoroughly study the manual prior to the use of the instrument, particularly whenever prescribed field adjustments are to be made
Some general principles of care, maintenance and servicing should be applied routinely matter for all survey equipment and supplies.
All equipment and tools should be kept clean and dry, particularly if they are to be transported or stored for any length of time.
Equipment should be wiped clean of dry mud or moisture prior to returning the equipment to the vehicle. The original painted or varnished surfaces should be repaired as often as needed to keep moisture from entering the wood.
Metal surfaces should be cleaned thoroughly. A coat of light oil should be applied to tapes and the metal parts of tools to prevent rusting during storage. Excess oil should be wiped off.
Before making the first set-up of the day, visually inspect the instrument for cracks, bumps, and dents. Check the machined surfaces and the polished faces of the lenses and mirrors. Try the clamps and motions for smooth operation (absence of binding or gritty sound).
DO NOT loosen or attempt to clean the internal surface of any lens.
Leave instruments in the case when it is not being used for any length of time, particularly if there is dust or moisture in the air. After an instrument has been used in a damp or extremely cold situation, special precautions must be taken to prevent condensation of moisture inside of the instrument. When working with the instrument in cold weather, it should be left in the carrying case in the vehicle overnight. If stored in a heated room overnight, the instrument must be removed from the carrying case. If the instrument is wet or frost-covered it should be removed from its case, and kept at room temperature to dry out.
Transport and store instruments in the right positions. Many instrument cases indicate the position in which they should be transported. Always transport the instruments in their carrying cases placed in a compartment cushioned firmly to protect them from jolting or excessive vibrations.
COURT INVALIDATES SECTION 5 OF LAGOS STATE SURVEY LAW
A Federal High Court sitting in Lagos has revoked Section 5 of the Lagos State Survey Law, which mandated surveyors to obtain written consent of the SurveyorSurveyor General of Lagos State before carrying out survey on state lands or any land obtained by the Lagos State Government.
Justice Daniel Osiagor of the Federal High Court in Lagos held that the Lagos State House of Assembly acted unconstitutionally in enacting the law.
The judge held that the Surveyors Council of Nigeria is the only body vested with the responsibility and authority to regulate and control survey practices and profession throughout the Federal Republic of Nigeria.
He further stated that the Surveyor General in the state does not have the power to demand and/or insist on counter-signing a survey plan prepared by a registered surveyor in Lagos state.
Justice Osiagor made the pronouncement while delivering judgement in suit number: FHC/L/CS/1789/2020, filed by seven surveyors; Adaranijo Rafiu, Kikelomo Aluko, Adedeji Olarewaju, Adams Olugbenga, Mekuleyi Samuel, Aliu Samuel and Fashina Adedapo—against the Surveyor General of Lagos State and 10 others.
Other defendants in the suit are Surveyors Council of Nigeria, Olatunbosun David, Adesina Adeleke, Akomolafe A.O, Odetunmobi O. Olufemi, Mrs Akintaro, Michael Adebisi Alonge, Surv. Egbeyemi Lateef, the Attorney General of Lagos State, Moyosore Onigbanjo, and the Attorney General of the Federation, Abubakar Malami.
The court held that the first Defendant lacked the powers to reject copies of any survey plans submitted by the plaintiffs and every other registered surveyor in Nigeria for lodgement, adding that he has no power to demand or insist on counter-signing a survey plan prepared by a Registered Surveyor.
The court also held that the Surveyor General of Lagos State lacks the powers to deny the plaintiffs or any registered surveyor consent to conduct survey on any parcel of land in Lagos State , whether owned by the Lagos State government, corporate bodies or private individuals.
HOW GIS LOCATION SHARING APP HELPED FIND A MISSING CHILD
How GIS Location Sharing App Helped Find A Missing Child
March 2020, 4-year-old Evelyn “Vardie” Sides vanished in the County area of the rural Alabama woods.
Authorities said she had been under the supervision of her septuagenarian caretaker, and walking her dog when she and the dog “just disappeared.” The caretaker called 911 and rescue teams swung into action.
Within hours, her parents and the community frantic with worry had organized a search that increased to include 400 volunteers, two helicopters, and more local authority search teams.
The volunteers trooped en masse into the woods, searching, calling out her name and that of her dog. Terrified with what they might find, scared that they may be losing time as night fell without a trace of the girl or her dog.
Hours later, there was still no sign of the little girl.
Where was four-year-old Vardie?
Prayers were said, routes were checked, paths were crossed and re-crossed but still, no one could find the beautiful little redhead angel.
Until Ken Busby was called to the scene some hours into the search.
As the county’s GIS coordinator, he had already printed out an aerial map of the surrounding area. But there was a better way to help the search effort.
He got his laptop and used live GIS to help with tracking everything in real-time.
Ken Busby contacted Esri’s Disaster Response Program (DRP) team for assistance. He requested location-sharing ArcGIS software to help him and other members of the response team coordinate their search and rescue efforts remotely and in real-time.
By the next morning, the team had access to an ArcGIS mobile app with location-sharing capabilities. It is now part of ArcGIS Field Maps.
After briefing everyone, all members of the search parties were able to download the location-sharing app to their mobile devices.
Each person that went out got a login for the app. Members of each search party showed on the map in the same color. That way, they could keep track of all the groupings
At the incident command post, the team set up monitors to display maps with real-time updates on the location of each search party. Ken Busby kept constant radio contact with the searchers to keep them on the right track.
Because of Lee County’s rural setting and wooded terrain, location sharing was vital. Using the GIS location tracking map, the command post could see in real-time where the search groups were and keep them heading in the right direction at all times.
With this technology, they were able to determine what areas the search team had covered so they didn’t end up going in circles.
They kept at it until they found footsteps in the woods on the second day.
They took pictures of the footsteps and sent them to Ken Busby who uploaded the geotagged pictures to ArcGIS Pro. From there, the response team was able to map the girl’s direction of travel based on the photo locations and ascertain where she had likely gone.
Both GIS mapping and location sharing capabilities allowed the search and rescue team to home in on a specific area of interest.
This proved to be a turning point for the search effort.
By narrowing the search area, the team was able to locate the girl and her dog on the third day.
Thankfully, they were unharmed. Little Vardie was reunited with her family and taken to the hospital for checks.
Although previously unfamiliar with the location sharing app, its ease of use and the quick response from Esri’s DRP team enabled the search and rescue team to speedily implement this new capability into its emergency operation.
The story above is just one example of the capabilities of GIS when put into total use. It can help security agencies locate people and objects in real-time. Help solve complex cases or just like in the case above, reunite families.
GIS is an amazing technological tool that empowers urban planners with enhanced visibility into data. GIS tools help monitor fluctuations over time, gauge the feasibility of proposed projects, evaluate the viability of location, modeling and predict the effects of trends on the environment.
GIS contributes to urban planning with its ability to better understand the current needs of a city, and then design to fulfill those needs. By processing geospatial data from satellite imaging, aerial photography, and remote sensors, GIS helps urban planners gain a detailed perspective on land and infrastructure.
7 WAYS GIS HELPS URBAN PLANNERS:
GIS expertise, tools, and technologies help run a variety of queries and analytics using data to evaluate how new construction will fit in with existing infrastructure and meet regulatory demands.
Using GIS software, researchers can generate visualizations of any area’s current environmental conditions to allow urban planners draw comparisons between the anticipated results of an area’s proposed development plans.
GIS software shows all relevant stakeholders exactly what the changes on the ground will look like. These visualizations can help planners make better decisions as regards building, construction, and planning.
Researchers and Geospatial experts can use GIS technologies to review and map the environmental impact of construction frameworks in a particular area for better decision making.
When experts perform land use analysis, it can provide a guide to new architectural development towards areas that are less prone to damage from natural and man-made disasters.
Geographic information can be synthesized with financial data and budgeting; this can help to revitalize an urban area in need of new businesses.
GIS can also map urban development and commercialization in an area to determine the best location for businesses to thrive.
Technological tools and advancements in GIS assist Urban planners across both public and private sector employ data-driven methods to address a wide array of issues that have long-term implications for communities and the surrounding landscape.
