Calvin Coopmans

A comparative evaluation of low-cost IMUs for unmanned autonomous systems

Inertial measurement units (IMUs) are widely used for navigation and calibration purposes on unmanned autonomous vehicles. This paper provides a comparative survey and evaluation of the low-cost IMUs focusing on both the possible sensor packages and the available software solutions. Several example IMUs are compared in detail including inertial only IMUs, GPS-coupled IMUs, and hobbyist-level IMUs. The future direction of low-cost IMUs are discussed including optical-flow-based solutions and collaborative IMUs.

A Survey and Categorization of Small Low-Cost Unmanned Aerial Vehicle System Identification

Remote sensing has traditionally be done with satellites and manned aircraft. While these methods can yield useful scientific data, satellites and manned aircraft have limitations in data frequency, process time, and real time re-tasking. Small low-cost unmanned aerial vehicles (UAVs) can bridge the gap for personal remote sensing for scientific data. Precision aerial imagery and sensor data requires an accurate dynamics model of the vehicle for controller development. One method of developing a dynamics model is system identification (system ID). The purpose of this paper is to provide a survey and categorization of current methods and applications of system ID for small low-cost UAVs. This paper also provides background information on the process of system ID with in-depth discussion on practical implementation for UAVs. This survey divides the summaries of system ID research into five UAV groups: helicopter, fixed-wing, multirotor, flapping-wing, and lighter-than-air. The research literature is tabulated into five corresponding UAV groups for further research.

ANALOGUE FRACTIONAL-ORDER GENERALIZED MEMRISTIVE DEVICES

Memristor is a new electrical element which has been predicted and described in 1971 by Leon O. Chua and for the first time realized by HP laboratory in 2008. Chua proved that memristor behavior could not be duplicated by any circuit built using only the other three elements (resistor, capacitor, inductor), which is why the memristor is truly fundamental. Memristor is a contraction of memory resistor, because that is exactly its function: to remember its history. The memristor is a two-terminal device whose resistance depends on the magnitude and polarity of the voltage applied to it and the length of time that voltage has been applied. The missing element—the memristor, with memristance M—provides a functional relation between charge and flux, dφ = Mdq. In this paper, for the first time, the concept of (integer-order) memristive systems is generalized to non-integer order case using fractional calculus. We also show that the memory effect of such devices can be also used for an analogue implementation of the fractional-order operator, namely fractional-order integral and fractional-order derivatives. This kind of operators are useful for realization of the fractional-order controllers. We present theoretical description of such implementation and we proposed the practical realization and did some experiments as well.Copyright

Low-cost UAV-based thermal infrared remote sensing: Platform, calibration and applications

Thermal infrared (TIR) remote sensing is recognized as a powerful tool for collecting, analyzing and modeling of energy fluxes and temperature variations. Traditional aircraft, satellite or ground TIR platforms can provide valuable regional-scale environmental information. However, these platforms have limitations, such as expensive cost, complicated manipulation, etc. In comparison, small unmanned aircraft systems (UAS) have many advantages in TIR remote sensing applications over traditional platforms. In this paper, a low-cost UAV-based TIR remote sensing platform: AggieAir-TIR is introduced. AggieAir-TIR is a small, low-cost, flexible TIR remote sensing platform, which was accomplished at the Center for Self Organizing and Intelligent Systems (CSOIS) in Utah State University (USU). The detailed introduction of AggieAir-TIR remote sensing platform is provided in the paper. Furthermore, a low-cost TIR imaging camera calibration experiment is designed, and the calibration results are provided. Based on this AggieAir-TIR remote sensing platform, many remote TIR image data collection and analysis projects can be effectively implemented.

Fractional-order memristive systems

This paper deals with the concept of (integer-order) memristive systems, which are generalized to non-integer order case using fractional calculus. We consider the memory effect of the fractional inductor (fractductor), fractional capacitor and fractional memristor. We also show that the memory effect of such devices can be also used for an analogue implementation of the fractional-order operator, namely fractional-order integral and fractional-order derivatives. This kind of operator is useful for realization of the fractional-order controllers. We present theoretical description of such implementation and we proposed the practical realization and did some simulations and experimental measurements as well.

AggieNav: A Small, Well Integrated Navigation Sensor System for Small Unmanned Aerial Vehicles

Small UAV performance is limited by the sensors used in the navigational systems. Several solutions of various complexity and cost exist, however no ready-made solutions exist for a high-accuracy, low-cost UAV system. Presented is AggieNav: a small, integrated navigational 6 degree-of-freedom with compass and GPS sensor package designed for ideal navigation of small UAVs. System, hardware, and embedded software design for the system is detailed.Copyright

AggieAir: An Integrated and Effective Small Multi-UAV Command, Control and Data Collection Architecture

Small UAV performance depends on an effective and efficient command system architecture. Based on an existing UAV system called Paparazzi, AggieAir is a full flight system capable of handling single or multiple UAVs with single or multiple payloads per airframe. System-level block diagrams are presented and specific details about implementation and results are provided.Copyright

A payload verification and management framework for small UAV-based personal remote sensing systems

Small, unmanned aerial systems are becoming more important in many fields, including civilian, scientific applications. Affordable systems that allow remote sensing at a small scale-personal remote sensing-are possible with proper system design. To assure data mission success (i.e., reliable and safe data collection) with low-cost or consumer-level sensor hardware, a well-designed payload management system is needed, along with sensor interface development and standardized testing frameworks for verification. This payload management system ensures a level of airworthiness for Data Mission Assurance. This paper presents such a system, along with motivations and choices such as system architecture and implementation, as well as standardized testing and verification. Data results from flight of a fixed-wing example payload is also included.

Pitch Loop Control of a VTOL UAV Using Fractional Order Controller

Pitch loop control is the fundamental tuning step for vertical takeoff and landing (VTOL) unmanned aerial vehicles (UAVs), and has significant impact on the flight. In this paper, a fractional order strategy is designed to control the pitch loop of a VTOL UAV. First, an auto-regressive with exogenous input (ARX) model is acquired and converted to a first-order plus time delay (FOPTD) model. Next, based on the FOPTD model, a fractional order [proportional integral] (FO[PI]) controller is designed. Then, an integer order PI controller based on the modified Ziegler-Nichols (MZNs) tuning rule and a general integer order proportional integral derivative (PID) controller are also designed for comparison following three design specifications. Simulation results have shown that the proposed fractional order controller outperforms both the MZNs PI controller and the integer order PID controller in terms of robustness and disturbance rejection. At last, ARX model based system identification of AggieAir VTOL platform is achieved with experimental flight data.

Small low-cost unmanned aerial vehicle system identification: A survey and categorization

Small low-cost unmanned aerial vehicles (UAVs) provide greater possibilities for personal scientific research than other conventional platforms such as satellites or manned aircraft. In order to provide precision aerial imagery or other scientific data, an accurate model of vehicle dynamics is needed for controller development and tuning. The purpose of this paper is to provide a survey of current methods and applications of system identification (system ID) for small low-cost UAVs. This survey divides UAVs into 5 groups: helicopter, fixed-wing, multirotor, flapping-wing, and lighter-than-air. The current state of system ID research with respect to various types of UAVs is reviewed based on research literature. System ID methods and application are tabulated for further research. Concluding remarks are given and applications for system ID methods to small low-cost UAVs are recommended.