This paper describes the concept, design and realization of a novel manipulator system for a multirotor aerial robot. The proposed manipulator system consists of three robotic arms attached to a multirotor frame. To overcome the limited payload capabilities in multirotor aerial platforms, the same set of on-board manipulators are used to realize various tasks, primarily the manipulation or grasping of objects of various sizes. Furthermore, they can provide aid in complex navigation tasks by doing physical, contact-based obstacle avoidance and are able to act as adaptive landing gear in uneven terrain. The design requirements and the analysis to realize these tasks is discussed. The proposal is supported with the successful demonstration of these tasks using the aerial multi manipulator system in an outdoor environment. GRAPHICAL ABSTRACT

In aerial manipulation, the position and size of a manipulator attached to an aerial robot defines its workspace relative to the robot. However, the working region of a multipurpose robot is determined by its task and is not always predictable prior to deployment. In this paper, the development of a multipurpose manipulator design for a three-armed UAV with a large workspace around its airframe is proposed. The manipulator is designed to be lightweight and slim in order to not disrupt the UAV during in-flight manipulator movements. In the experiments, we demonstrate various advanced and critical tasks required of an aerial robot when deployed in a remote environment, focusing on the landing and docking tasks, which is accomplished using a single manipulator system.

In this work, a new method for aerial robot remote sensing using stereo vision is proposed. A variable baseline and flexible configuration stereo setup is achieved by separating the left camera and right camera on two separate quadrotor aerial robots. Monocular cameras, one on each aerial robot, are used as a stereo pair, allowing independent adjustment of the pose of the stereo pair. In contrast to conventional stereo vision where two cameras are fixed, having a flexible configuration system allows a large degree of independence in changing the configuration in accordance with various kinds of applications. Larger baselines can be used for stereo vision of farther away targets while using a vertical stereo configuration in tasks where there would be a loss of horizontal overlap caused by a lack of suitable horizontal configuration. Additionally, a method for the practical use of variable baseline stereo vision is introduced, combining multiple point clouds from multiple stereo baselines. Issues from using an inappropriate baseline, such as estimation error induced by insufficient baseline, and occlusions from using too large a baseline can be avoided with this solution.

UAVs are one of the fastest types of robots that can be deployed in a remote environment. Unfortunately, they have a limited flight time and therefore may need to stop occasionally in an unknown, uncontrolled area. However, conventional UAVs require flat and stationary surfaces for a safe landing and take-off. Some studies on adaptive landing approach for UAVs can be found in the past, but adaptive take-off from non-flat surfaces has not been discussed for the most part, yet. In this work, we discuss the problems associated with a conventional UAV take-off from non-flat surfaces and provide a novel approach for UAV take-off from a sloped or rocking surface. We also discuss the design of a novel multitasking three-arm aerial manipulator system with parallel link mechanism and achieve the above-mentioned task. With experiments, we show that the system can provide stability for a UAV landing on a rocking surface that allows for a safe take-off.

This paper proposes a mechanism for a multirotor unmanned aerial vehicle to perch at the tip of a cylindrical object. The proposed mechanism does not require an additional actuator such as a motor by converting its own weight into a gripping force at the time of perching. It also shows that a gripping force larger than its own weight can be generated based on a boost mechanism by appropriately selecting the design parameters. In addition, the proposed mechanism has a structure that can be not only used for perching at the tip of a cylindrical object, but also as a landing gear when landing on flat ground. Furthermore, we attached a depth camera to the proposed mechanism and obtain color and depth images of the target object to be grasped while flying so that automatic positioning can be executed based on the acquired images. Through indoor and outdoor experiments, it was confirmed that the expected perching and landing could be performed.

Landmine contamination remains a critical barrier to post-conflict recovery, necessitating detection methods that are safe, scalable, and cost-effective. This study investigates drone-based detection of relevant plants in a mixed vegetation as required for future plant-based biodetection of explosive remnants derived from landmines. Field experiments were conducted in Ukraine and Denmark using oilseed radish and winter rapeseed as indicator biosensors due to their suitability for genetic modification and resilience in diverse climates. High-resolution RGB and multispectral imagery were collected under varying conditions, including flight altitude, time of day, and land preparation. We evaluated plant visibility at different altitudes and trained models to detect the plants and developed strategies to streamline annotation. Practical deployment challenges, such as seeding and growth of indicator plants in non-cultivated and hazardous soils are also considered. Our findings demonstrate the potential of aerial biosensor monitoring and offer insights into the development of plant-based landmine detection systems suitable for real-world applications.