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The “System” in UAS
Published in Douglas M. Marshall, R. Kurt Barnhart, Eric Shappee, Michael Most, Introduction to Unmanned Aircraft Systems, 2016
Joshua Brungardt, Richard Kurt Barnhart
In reference to the missions of surveillance and aerial sensing, sensor payloads come in many different forms for different missions. Examples of sensors can include electro-optical (EO) cameras, thermal infrared (IR) cameras, spectral sensors, synthetic aperture radars (SAR), or laser range finder/designators. Optical sensor packages (cameras) can be either installed by permanently mounting them to the UAS aircraft giving the sensor operator a fixed view only, or they can employ a mounted system called a gimbal or turret (Figure 3.5). A gimbal or turret mounting system gives the sensor a predetermined range of motion usually in three axes. The gimbal or turret receives input either through the autopilot system or through a separate receiver. Some gimbals are also equipped with vibration isolation, which reduces the amount of aircraft vibration that is transmitted to the camera thus requiring less electronic image stabilization to produce a clear image or video. Vibration isolation can be performed by either an elastic/rubber mounting or using an electronic gyrostabilization system.
The “System” in UAS
Published in R. Kurt Barnhart, Douglas M. Marshall, Eric J. Shappee, Introduction to Unmanned Aircraft Systems, 2021
Joshua Brungardt, Kurt Carraway
Optical sensor packages can be permanently mounted on the UAS aircraft, giving the sensor operator a fixed view only; or they can use a mounting system called a gimbal or turret (Figure 3.5). A gimbal or turret mounting system gives the sensor a predetermined range of motion, usually in three axes. The gimbal or turret receives input either through the autopilot system or through a separate receiver. Some gimbals are also equipped with vibration isolation, which reduces the amount of aircraft vibration that is transmitted to the camera (image stabilization) and produces a clearer image or video. Vibration isolation can be performed by an elastic/rubber mounting, or with an electronic gyrostabilization system.
Introduction
Published in Yasmina Bestaoui Sebbane, Intelligent Autonomy of Uavs, 2018
A UAS is a system of systems (SoS): a set of complementary technologies brought together to fulfill a specific task. The component systems that make up the UAS include the air vehicle, the ground-control station, payloads, data link, and support equipment [21,90]. UAS capabilities, such as remote human crew interaction enabled by wireless communication and autonomous vehicle functionality, are central to these systems. The basic design has a micro-controller that acts as a flight control system (FCS), usually with actuators, a radio receiver, electronic speed control, and a battery. In addition, inertial measurement unit, gyroscopes and other sensors are added to increase the mid-air stability of the UAV and a GPS device can be used for navigation. Most UAVs also carry at least one camera for aerial imagery, and a gimbal for added image stability. Additionally, other sensors can be attached, though there is a trade-off with increased functionality and weight. Ultrasonic sensors or lidars can be directly integrated in obstacle avoidance operations, while laser range finders provide range measurements for obstacle detection and mapping of 3-D environments. Visual stereo or monocular camera systems are able to provide depth measurements for obstacle avoidance and mapping tasks. High-performance cameras are mostly used, many with useful zooms. Gimbal technology is necessary to capture quality aerial photos, film or 3-D imagery. The gimbal allows for any vibration from the UAV to not reach the camera. Additionally, the gimbal can be tightly coupled with the inertial measurement unit (IMU) for visual-inertial ego-motion estimation and the raw image stream is also required for infrastructure inspection [65].
Vehicle trajectory data extraction from the horizontal curves of mountainous roads
Published in Transportation Letters, 2022
V.A. Bharat Kumar Anna, Suvin P. Venthuruthiyil, Mallikarjuna Chunchu
The data were collected during day and dry weather conditions. In this experiment, the aerial footage was recorded with a resolution of 2704 × 1520 pixels and at a rate of 24 frames per second. The three-axis gimbal of the drone reduces minor roll rotation and drift by compensating sudden jerks or movement of the drone for capturing smooth motion videos. Table 2 presents the technical features of the drone used in the controlled experiment. Further, a field survey was conducted using the Total Station to measure the field reference points (coordinate points) at an average distance of 10 to 20 meters, which is essential for geo-referencing the field coordinates.
How accurate are small drones for measuring microscopic traffic parameters?
Published in Transportation Letters, 2019
Emmanouil N. Barmpounakis, Eleni I. Vlahogianni, John C. Golias, Adam Babinec
Firstly, the first step to reduce rough bias is by attaching a gimbal support system to the camera. In this way, the gimbal allows the rotation of the camera about a single axis despite the drone’s pitching and rolling, and therefore the camera stays horizontal regardless the motion of the drone. It should be noted that most of the times, the gimbal automatically compensates the movement of the drone using calibrated electric motors.