Robust Intrinsic and Extrinsic Calibration of RGB-D Cameras

Color-depth cameras (RGB-D cameras) have become the primary sensors in most robotics systems, from service robotics to industrial robotics applications. Typical consumer-grade RGB-D cameras are provided with a coarse intrinsic and extrinsic calibration that generally does not meet the accuracy requirements needed by many robotics applications (e.g., highly accurate 3D environment reconstruction and mapping, high precision object recognition and localization, ...). In this paper, we propose a human-friendly, reliable and accurate calibration framework that enables to easily estimate both the intrinsic and extrinsic parameters of a general color-depth sensor couple. Our approach is based on a novel two components error model. This model unifies the error sources of RGB-D pairs based on different technologies, such as structured-light 3D cameras and time-of-flight cameras. Our method provides some important advantages compared to other state-of-the-art systems: it is general (i.e., well suited for different types of sensors), based on an easy and stable calibration protocol, provides a greater calibration accuracy, and has been implemented within the ROS robotics framework. We report detailed experimental validations and performance comparisons to support our statements

RFID Localisation For Internet Of Things Smart Homes: A Survey

The Internet of Things (IoT) enables numerous business opportunities in fields as diverse as e-health, smart cities, smart homes, among many others. The IoT incorporates multiple long-range, short-range, and personal area wireless networks and technologies into the designs of IoT applications. Localisation in indoor positioning systems plays an important role in the IoT. Location Based IoT applications range from tracking objects and people in real-time, assets management, agriculture, assisted monitoring technologies for healthcare, and smart homes, to name a few. Radio Frequency based systems for indoor positioning such as Radio Frequency Identification (RFID) is a key enabler technology for the IoT due to its costeffective, high readability rates, automatic identification and, importantly, its energy efficiency characteristic. This paper reviews the state-of-the-art RFID technologies in IoT Smart Homes applications. It presents several comparable studies of RFID based projects in smart homes and discusses the applications, techniques, algorithms, and challenges of adopting RFID technologies in IoT smart home systems.Comment: 18 pages, 2 figures, 3 table

Innovative mechanism to identify robot alignment in an automation system

Robotic applications are commonly used in industrial automation systems. Such systems are often comprised of a series of equipment, including robotic arms, conveyors, a workspace, and fixtures. While each piece of equipment may be calibrated with the highest precision, their alignment in relation to each other is an important issue in defining the accuracy of the system. Currently, a variety of complex automated and manual methods are used to align a robotic arm to a workspace. These methods often use either expensive equipment or are slow and skill-dependent. This paper presents a novel low-cost method for aligning an industrial robot to its workcell at 6 degrees of freedom (DoF). The solution is new, simple and easy to use and intended for the SMEs dealing with low volume, high complexity automated systems. The proposed method uses three dial indicators mounted to a robot end effector and a fixed measurement cube, positioned on a workcell. The robot is pre-programmed for a procedure around the cube. The changes on the dial indicators are used to calculate the misalignment between the robot and the workcell. Despite simplicity of the design, the solution is supported with complex real-time mathematical calculations and proven to identify and eliminate misalignment up to 3mm and 5 degrees to an accuracy of 0.003mm and 0.002 degrees: much higher than the precision required for a conventional industrial robot. In this article, the authors describe a proposed solution, validate the computation both theoretically and through a laboratory test rig and simulation

Progress in industrial photogrammetry by means of markerless solutions

174 p.La siguiente tesis está enfocada al desarrollo y uso avanzado de metodologías fotogramétrica sin dianas en aplicaciones industriales. La fotogrametría es una técnica de medición óptica 3D que engloba múltiples configuraciones y aproximaciones. En este estudio se han desarrollado procedimientos de medición, modelos y estrategias de procesamiento de imagen que van más allá que la fotogrametría convencional y buscan el emplear soluciones de otros campos de la visión artificial en aplicaciones industriales. Mientras que la fotogrametría industrial requiere emplear dianas artificiales para definir los puntos o elementos de interés, esta tesis contempla la reducción e incluso la eliminación de las dianas tanto pasivas como activas como alternativas prácticas. La mayoría de los sistemas de medida utilizan las dianas tanto para definir los puntos de control, relacionar las distintas perspectivas, obtener precisión, así como para automatizar las medidas. Aunque en muchas situaciones el empleo de dianas no sea restrictivo existen aplicaciones industriales donde su empleo condiciona y restringe considerablemente los procedimientos de medida empleados en la inspección. Un claro ejemplo es la verificación y control de calidad de piezas seriadas, o la medición y seguimiento de elementos prismáticos relacionados con un sistema de referencia determinado. Es en este punto donde la fotogrametría sin dianas puede combinarse o complementarse con soluciones tradicionales para tratar de mejorar las prestaciones actuales

Micro-manufacturing : research, technology outcomes and development issues

Besides continuing effort in developing MEMS-based manufacturing techniques, latest effort in Micro-manufacturing is also in Non-MEMS-based manufacturing. Research and technological development (RTD) in this field is encouraged by the increased demand on micro-components as well as promised development in the scaling down of the traditional macro-manufacturing processes for micro-length-scale manufacturing. This paper highlights some EU funded research activities in micro/nano-manufacturing, and gives examples of the latest development in micro-manufacturing methods/techniques, process chains, hybrid-processes, manufacturing equipment and supporting technologies/device, etc., which is followed by a summary of the achievements of the EU MASMICRO project. Finally, concluding remarks are given, which raise several issues concerning further development in micro-manufacturing

Accuracy Evaluation of Dense Matching Techniques for Casting Part Dimensional Verification

Product optimization for casting and post-casting manufacturing processes is becoming compulsory to compete in the current global manufacturing scenario. Casting design, simulation and verification tools are becoming crucial for eliminating oversized dimensions without affecting the casting component functionality. Thus, material and production costs decrease to maintain the foundry process profitable on the large-scale component supplier market. New measurement methods, such as dense matching techniques, rely on surface texture of casting parts to enable the 3D dense reconstruction of surface points without the need of an active light source as usually applied with 3D scanning optical sensors. This paper presents the accuracy evaluation of dense matching based approaches for casting part verification. It compares the accuracy obtained by dense matching technique with already certified and validated optical measuring methods. This uncertainty evaluation exercise considers both artificial targets and key natural points to quantify the possibilities and scope of each approximation. Obtained results, for both lab and workshop conditions, show that this image data processing procedure is fit for purpose to fulfill the required measurement tolerances for casting part manufacturing processes.This research was partially funded by ESTRATEUS project (Reference IE14-396). given are accurate and use the standard spelling of funding agency names at https://search.crossref.org/funding, any errors may affect your future funding

Traceability of on-machine tool measurement: a review

Nowadays, errors during the manufacturing process of high value components are not acceptable in driving industries such as energy and transportation. Sectors such as aerospace, automotive, shipbuilding, nuclear power, large science facilities or wind power need complex and accurate components that demand close measurements and fast feedback into their manufacturing processes. New measuring technologies are already available in machine tools, including integrated touch probes and fast interface capabilities. They provide the possibility to measure the workpiece in-machine during or after its manufacture, maintaining the original setup of the workpiece and avoiding the manufacturing process from being interrupted to transport the workpiece to a measuring position. However, the traceability of the measurement process on a machine tool is not ensured yet and measurement data is still not fully reliable enough for process control or product validation. The scientific objective is to determine the uncertainty on a machine tool measurement and, therefore, convert it into a machine integrated traceable measuring process. For that purpose, an error budget should consider error sources such as the machine tools, components under measurement and the interactions between both of them. This paper reviews all those uncertainty sources, being mainly focused on those related to the machine tool, either on the process of geometric error assessment of the machine or on the technology employed to probe the measurand