Denis Kotarski

By Denis Kotarski and Josip Kasać

Unmanned aerial vehicles (UAVs) are autonomous or remotely guided aircraft, which can potentially carry out a wide range of tasks. Multirotor type of UAV has unique ability to perform vertical take-off and landing (VTOL), a stationary and low-speed flight where certain configurations can achieve very complex and precise movements. Therefore, they are suitable for performing tasks such as delivery of first aid kit, firefighting, infrastructure inspection, aerial video, and many others. In this chapter, a generalized control allocation scheme for a multirotor UAV is presented, which describes the mapping of rotor angular velocities to the control vector of the aircraft. It enables control and design of multirotor configurations with diverse geometrical arrangement and characteristics of the propulsion subsystem depending on the task, which multirotor has to carry out. The inverted scheme, which is implemented as a motor mixer, maps the control inputs into a set of aircraft actuator outputs.

Part of the book: Drones

By Denis Kotarski, Petar Piljek and Josip Kasać

Unmanned aerial vehicles (UAVs) have proven to be an advanced tool for a variety of applications in the civilian and military sectors. Different categories of UAVs are used in various missions and are also the subject of numerous researches. Due to their characteristics and potential in specific conditions, multirotor UAVs imposes itself as a solution for many tasks, including transport. This chapter presents a conceptual solution of autonomous cargo transportation where the primary research objective is the design of a heavy lift multirotor UAV system. The process of designing a multirotor UAV that can carry heavy lift cargo is quite challenging due to many parameters and constraints. Five selected series of electric propulsion systems are analyzed, with different multirotor configurations, and results are graphically displayed for payloads from 10 kg up to 100 kg.

Part of the book: Self-Driving Vehicles and Enabling Technologies

By Petar Piljek, Nino Krznar, Matija Krznar and Denis Kotarski

Rapid prototyping technologies have enabled a major step forward in the development of a very wide range of products, especially in the field of mechatronic systems. These technologies are largely related to additive manufacturing (AM), so-called 3D printing which is, in addition to product development, also suitable for the fabrication of mechatronic systems that are not intended for series production. In this chapter, a framework for the AM of specialised multirotor unmanned aerial vehicles (UAVs) parts is proposed and described for three AM technologies—fused deposition modelling (FDM), selective laser sintering (SLS), and stereolithography (SLA). A different approach to parts design is shown where the main problems are addressed and guidelines for parts manufacturing are given. Special emphasis is related to the mechanical characteristics and low weight of the manufactured parts that are merged with carbon fibre segments. The manufactured (printed) parts are mounted in functional assemblies and preliminarily tested.

Part of the book: Trends and Opportunities of Rapid Prototyping Technologies

By Petar Piljek, Marko Pranjić, Denis Kotarski and Tomislav Petanjek

Continuous demands for growth in agricultural productivity and modern demands for the sustainable agricultural approach are bringing farmers into a new technological era. With all the limitations and risks, precision agriculture and other related technologies show great potential in solving the challenges of sustainable and more efficient agricultural production. Nowadays, unmanned aerial vehicles (UAVs) are able to perform a wide range of agricultural tasks, from data collection to smart spraying. This chapter presents the concept of a modular autonomous robotic system that, based on available technologies, materials, and system components, can be produced and applied in precision agriculture. The primary purpose of such a system, which consists of a multirotor UAV and docking station, is to save the time required to perform the task and to reduce environmental and soil pollution. Several problems have been addressed, which affect performance and energy consumption, for example, of spraying a field crop.

Part of the book: Digital Agriculture, Methods and Applications

By Denis Kotarski, Tomislav Šančić, Martin De Bona and Petar Piljek

Using semiautonomous and autonomous vehicles to perform various missions can lead to increased safety and efficiency. With all risks and limitations included, great potential exists in the integration of unmanned aerial and ground vehicles into heterogeneous robotic systems. Considering the great advances that have been made in terms of path planning, localization, control, coordinated motion, cooperative exploration, and others, such heterogeneous systems are suitable for a very wide range of tasks. In this research, the architecture that includes the ground robot as a base and the aerial robot as an extension to 3D space is examined. Such an architecture is scalable, it can be used for a wide range of missions from data collection to smart spraying. The ground robot system has been prototyped with a tracked differential drive configuration. Preliminary tests will serve as guidelines for further steps in the system development.

Part of the book: Autonomous Vehicles