Drones and Drone Technology
UAV drone technology is consistently evolving as new innovation and large investment are bringing more advanced drones/ UAV’s to the market every few months. Unmanned aerial vehicle innovation covers everything from the aerodynamics of the drone, materials in the production of the physical UAV, to the circuit boards, chipset and programming, which are the minds of the automaton.
How Drones Work
A regular unmanned airplane is made of light composite materials to lessen weight and increment mobility. This composite material quality permits military automatons to voyage at amazingly high altitudes.
UAV drones are equipped with different state of the art technology such as infrared cameras, GPS and laser (consumer, commercial and military UAV). Drones are controlled by remote communication system systems (GSC) and also mentioned as a ground cockpit.
An unmanned aerial vehicle system has 2 sub parts, one being the drone itself and the other being control system.
The nose of the unmanned aeronautical vehicle is the place all the sensors and navigational frameworks are available. The remaining body is brimming with drone/ UAV technologies and frameworks since there is no space required to accommodate people.
The engineering materials involved in building the drone are highly complex composites designed to soak up vibration, which decrease the sound produced.
Drone Types And UAV Technology
UAV drones are available in a good number of shapes and sizes, with the most important being mostly used for military purposes like the Predator drone. The next in size are unmanned aircraft, which have fixed wings and require short runways. These are generally used to cover large sections of land, working in areas such as geographical surveying or to combat wildlife poaching.
VTOL Drones
Next in size for drones are what’s referred to as VTOL drones. These are generally quadcopters but not all. VTOL drones can begin , fly, hover and land vertically. The exact meaning of VTOL is “Vertical Take-Off and Landing”.
Radar Positioning & Return Home
The latest drones have dual Global Navigational Satellite Systems (GNSS) such as GPS and GLONASS.
Drones can fly in both GNSS and non satellite modes. For example, DJI drones can fly in P-Mode (GPS & GLONASS) or ATTI mode, which doesn’t use GPS.
Highly accurate drone navigation is very important when flying, especially in drone applications such as creating 3D maps, surveying landscape and SAR (Search & Rescue) missions.
When a quadcopter is first switched on, it searches and detects Global Navigational Satellite Systems. High end GNSS systems use Satellite Constellation technology. Basically, a satellite constellation is a group of satellites working together giving coordinated coverage and are synchronized, so that they overlap well in coverage. Pass or coverage is the period in which a satellite is visible above the local horizon.
UAV Drone GNSS On Ground Station Remote Controller
The radar technology will signal the following on the remote controller display :
- Signal that enough drone GNSS satellites have been detected and the drone is ready to fly.
- Display the current position and location of the drone with respect to the pilot.
- Record the home point for ‘Return To Home’ safety feature.
Most of the latest UAVs have 3 types of Return to Home drone technology as follows;
- Pilot initiated return to home by pressing button on Remote Controller or in an app.
- A low battery level, where the UAV will fly automatically back to the home point.
- Loss of contact between the UAV and Remote Controller, with the UAV flying back automatically to its home point.
Obstacle Detection And Collision Avoidance Technology
The latest high tech drones are now equipped with collision avoidance systems. These use obstacle detection sensors to scan the surroundings, while software algorithms and SLAM technology produce the images into 3D maps allowing the drone to sense and avoid. These systems fuse one or more of the following sensors to sense and avoid;
- Vision Sensor.
- Ultrasonic.
- Infrared.
- Lidar.
- Time of Flight (ToF).
- Monocular Vision.
The DJI Mavic 2 Pro and Mavic 2 Zoom have obstacle sensing on all 6 sides. The Mavic 2 uses both Vision and Infrared sensors fused into a vision system known as omni-directional Obstacle Sensing.
The DJI Mavic 2 obstacle sensing system is top drone technology. The Mavic 2 will sense objects, then fly around obstacles in front. It can do the same when flying backwards. Or hover if it is not possible to fly around the obstacle.
This technology is known as APAS (Advanced Pilot Assistance System) on the DJI Mavic 2 and Mavic Air drones.
In December 2019, the Skydio 2 drone was released. This also has obstacle avoidance on all sides.
The Skydio 2 autonomy technology visualizes and calculates what’s happening around the drone. It can then intelligently predict what will happen next and will make accurate decisions multiple times a second.
The Skydio 2 quadcopter uses 6 x 4k cameras to build a 3D map of its surroundings, which will include trees, people, animals, cars, buildings and more.
Gyroscope Stabilization, IMU And Flight Controllers
Gyro stabilization technology give the UAV drone its smooth flight capabilities.
The gyroscope works almost instantly to the forces moving against the drone, keeping it flying or hovering very smoothly. The gyroscope provides essential navigational information to the central flight controller.
The inertial measurement unit (IMU) works by detecting the current rate of acceleration using one or more accelerometers. Changes in rotational attributes like pitch, roll and yaw are detected by the IMU using one or more gyroscopes. Some IMU include a magnetometer to help with calibration against orientation drift.
The Gyroscope may be a component of the IMU and therefore the IMU is an important component of the drones flight controller. The flight controller is the central unit (mind) of the drone.
UAV Drone Propulsion Technology
The propulsion system (motors, electronic speed controllers and propellers) are the drone technology, which move the UAV into the air and to fly in any direction or hover. On a quadcopter, the motors and propellers work in pairs with 2 motors / propellers rotating clockwise (CW Propellers) and 2 motors rotating Counter Clockwise (CCW Propellers).
They receive data from the flight controller and the electronic speed controllers (ESC) on the drone motor direction to either fly or hover.
The Electronic Speed Controllers signal to the drone motors information on speed, braking and also provide monitoring and fault tolerance on the drone motors.
Realtime Telemetry Flight Parameters
Nearly all drones have a Ground Station Controller (GSC) or a smartphone app, allowing you to fly the drone and to keep track of the current flight telemetry. Telemetry data showing on the remote controller many include UAV range, height, speed, GNSS strength, remaining battery power and warnings.
FPV (First Person View) is used by many UAV drone ground controllers, which transmit the video from the drone to the controller or mobile device.
Internal Compass & Failsafe Function
Allows the UAV drone and remote control system to know exactly its flight location. A home point can be set and this is the location the drone will return to, if the drone and the remote control system stop connecting. This is also known as “fail-safe function”.
FPV Live Video Transmission Drone Technology
FPV expands to — First Person View. A camcorder is mounted on the unmanned elevated vehicle and this camera communicates the live video to the pilot on the ground. The ground pilot is flying the airplane as though they were ready the airplane as opposed to taking a gander at the airplane from the pilot’s genuine ground position.
FPV allows the unmanned aircraft to fly much higher and further than you can from looking at the aircraft from the ground. First Person View allows for more precise flying especially around obstacles.
FPV allows unmanned aerial vehicles to fly very easily indoors, or through forests and around buildings.
The exceptionally fast growth and development of the drone racing league wouldn’t be possible without FPV live video transmission technology.
This FPV technology uses radio wave to transmit and receive the live video.
The drone features a multi-band wireless FPV transmitter inbuilt along side an antenna. Depending on the drone, the receiver of the live video signals are often either the remote unit, a computer, tablet or smartphone device.
Gimbals & Tilt Control
Gimbal technology is vital to capture quality aerial photos, film or 3D imagery.
The gimbal allows the camera to tilt while in flight, creating unique angles. More importantly, the gimbal reduces camera vibrations caused during the flight of the drone. These are mostly 3 axis stabilized gimbals with 2 working modes. Non-FPV mode and FPV mode.
Drones With Sensors To Create 3D Maps And Models Using Sensor Fusion
Lidar, Multispectral and Photogrammetry sensors are being used to build 3D models of buildings and landscapes. Low light night vision and Thermal vision sensors are being used on drones to scan buildings and landscapes to assist in agriculture, firefighting, search and rescue.
Drones can carry different sensors with the software bringing together a spectrum of data together for better results. This technology is known as sensor fusion and works as follows;
Sensor fusion is a software, which intelligently combines data from several different sensors such as a thermal camera and a regular RGB camera sensor for the purpose of improving application or system performance. Consolidating information from numerous sensors remedies the mistakes from singular sensors to figure exact position and direction data.
For instance, multispectral sensors on drones can create Digital Elevation Maps (DEMS) of land areas to provide precision data on the health of crops, flowers, fauna, shrubs and trees.
Recently, drones using Time-of-Flight (ToF) sensors came on the market. ToF sensors, also known as “Flash Lidar” can be used on their own or with RGB and regular lidar sensors to provide various solutions across the sectors.
ToF depth ranging camera sensors can be used for object scanning, indoor navigation, obstacle avoidance, gesture recognition, tracking objects, measure volumes, reactive altimeters, 3D photography, augmented reality games and much more.
Flash lidar Time-of-Flight cameras have a huge advantage over other technologies, as it is able to measure distances to objects within a complete scene in a single shot.
For lidar and photogrammetry mapping, the UAV is programmed to fly over an area autonomously, using waypoint navigation. The camera on the drone will take photographs at 0.5 or 1 second intervals. These photos are then stitched together using specialized photogrammetry software to create the 3D images.
Conclusion
Personally, I am much more fascinated by the drone technology and its uses in everyday life to assist with saving lives in search and rescue, site surveying by many sectors, aerial cinematography or just to fly for fun by the hobbyist.
Up to a few years ago, much of the technology from military drones made their way into the consumer and business drones.
In the past few years, we have seen massive investment in drones especially in the business and consumer drone sector. Drone technology and innovation has really leaped forwarded in the past few years.
