Search results

This paper aims to present a fully actuated aerial manipulator (AM) with a robust motion/force hybrid controller for conducting contact-typed inspection tasks in industrial plants.

An AM is designed based on a hexarotor with tilted rotors and a rigidly attached end effector. By tilting the rotors, the position and attitude of the AM can be controlled independently, and the AM can actively exert forces on industrial facilities through the rigidly attached end effector. A motion/force hybrid controller is proposed to perform contact-typed inspection tasks. The contact-typed inspection task is divided into the approach phase and the contact phase. In the approach phase, the AM automatically approaches the contact surface. In the contact phase, a motion/force hybrid controller is used for contact-typed inspection. Finally, a disturbance observer (DOB) is used to estimate external disturbances and used as feedforward compensation.

The proposed AM can slowly approach the contact surface without significant impact in the contact phase. It can realize constant force control in the direction normal to the contact surface in the contact phase, whereas the motion of the remaining directions can be controlled by the operator. The use of the DOB ensures the robustness of the AM in the presence of external wind disturbances.

A fully actuated AM system with a robust motion/force hybrid controller is proposed. The effectiveness of the proposed AM system for conducting contact-typed industrial inspection tasks is validated by practical experiments.

There are many methods and solutions to improve any process, and stay within the established control limits. Statistically analyzed data, received from inspection sensors and other devices, are one of them. Automated inspection sensors and systems are effective tools for controlling variation and obtaining process related knowledge. Automated inspection methods, discussed in this paper, represent an important, nevertheless not the only methods, that lead to process improvement, the ultimate goal of total quality management and control (TQM/TQC). Inspection, as part of the feedback control loop of the overall TQM/TQC process, involves the continual satisfaction of customer requirements at lowest cost by harnessing the efforts of everybody in the company. The key question in any inspection system is as follows: Are the measured values within tolerance, or not, and if they are outside the tolerance limits, why did we produce those parts in the first place?

The purpose of this paper is to propose an automatic optical inspection system for measuring the surface profile of a microlens array.

The system set‐up was constructed according to the principle of the Fizeau interferometer. After capturing the ring interference fringe images of the microlens with a camera, the diameter, profile information and optical properties were analyzed through a microlens surface profile algorithm using innovative image pre‐processing with a precision of less than 0.09 micron.

By integrating with the genetic algorithm, the XY‐Table shortest moving path of the system is calculated to achieve the purpose of high‐speed inspection and automatic microlens array surface profile measurement.

The measurement results of this system were also compared with other systems, including the atomic force microscope and stylus profiler, to verify the measurement precision and accuracy of this system.

The introduction of time compression technologies into the modern mechanical design process is now well established. Most major automotive and aerospace companies have invested, as have their Tier 1 suppliers. It has been identified that a bottleneck affecting all aspects of the cycle is the measurement process. In this paper we shall discuss potential benefits of adopting non‐contact techniques. In section 1 we discuss the need for rapid physical measurement within the context of the mechanical design process. The processes required for surface creation and inspection are discussed in Section 2 with regard to contact and non‐contact measurement. Section 3 reviews the operating principles of commercially available non‐contact systems. Finally Section 4 discusses practical issues relating to the implementation and use of non‐contact systems in the manufacturing environment.

Description of current 4DI three dimensional imaging system, a proprietary 3D vision sensing technology available from Intelligent Automation (IA), and introduction to the recently developed, next generation, HiPART (High‐resolution Phase Angle Resolved Triangulation) gauge sensor developed by a consortium in which IA participated. Both are non‐contact electro‐optical systems capable of being applied to a wide realm of inspection possibilities for the metrology industry. The HiPART sensor is one of the key non‐contact measurement technologies developed by potential end‐users of the technology, high‐technology advancement companies, and the US government in a collaborative effort to improve the measurement and inspection processes of manufactured parts. Specifications and benefits of the sensors, and examples of possible uses are outlined, illustrating the advantage that the 4DI and HiPART sensor have over standard coordinate measuring machines (CMMs). These sensors are actively being commercialized by IA, a custom automation and machine vision development company, which is introducing it to the appropriate markets.

Quality control and part inspection add no monetary value to a product, yet are essential processes for manufacturers who want to maintain product quality. Mass‐produced custom parts require processes that are able to perform high frequency of inspection, whilst providing rapid response to unanticipated changes in parameters such as throughputs, dimensions and tolerances. Frequent inspection of these parts significantly impacts inspection times involved. A method of reducing the impact of high‐frequency inspection on production rates is needed. This paper addresses these issues.

This paper involves the research, design, construction, assembly and implementation of an automated apparatus, used for the visual inspection of moving custom parts. Inspection occurred at user‐defined regions of interest (ROIs). Mechatronic Engineering principles are used to integrate sensor articulation, image acquisition and image‐processing systems. The apparatus is tested in a computer‐integrated manufacturing (CIM) cell for quantifying results.

Specified production rates are maintained whilst performing high frequencies of inspection, without stoppage of parts along the production line.

The limitations of these results lie in the fact that they are suited only to the speed of the CIM cell. Higher inspection rates may be achieved, and changes in the design may be required in order to make the apparatus more suitable to industrial applications.

The paper shows that it is possible to maintain high standards of quality control without significantly affecting production rates.

Current research does not focus on maintaining production rates whilst inspecting custom parts. The use of ROI inspection for moving custom parts is a relatively new concept.

Geometric errors are common in metallic bent tubular parts. Thus, tubes should be inspected and fixed before welding with the joints first. After welding, the relative position of the joints is also necessary to be inspected to judge whether the tube can be assembled reliably. Therefore, the inspection plays an important role in the tube’s assembly. The purpose of this paper is to propose a multi-vision-based system designed to inspect the tube and the relative position of the joints.

For the tube inspection, the small cylinders are taken as the primitives to reconstruct the tube using the multi- vision-based system. Then, any geometric error in the tube can be inspected by comparing the reconstructed models and designed ones. For joints’ inspection, authors designed an adapter with marked points, by which the system can calculate the relative position of the joints.

The reconstruction idea can recognise the line and arc segments of a tube automatically and resolve the textureless deficiency of the tube’s surface. The joints’ inspection method is simple in operation, and any kinds of joints can be inspected by designing the structure of the adapters accordingly.

By experimental verification, the inspection precision of the proposed system was 0.17 mm; the inspection time was within 2 min. Thus, the system developed can inspect a tube effectively and automatically. Moreover, authors can determine how the springback of the arcs behaves, allowing in-process springback prediction and compensation, which can reduce geometric errors in the tubes given the present bending machine accuracy.

A pressure contact connector design was evaluated based on contact load and tested under temperature cycling. The damage induced on gold contact surfaces in a pressure contact connector was examined using visual inspection methods. The connector was subjected to mating and unmating operations, as well as repeated thermal excursions to determine environmental factors which would accelerate damage. Pressure indentations and wear tracks were found on the contact bumps and fingers resulting from the temperature cycling. This wear of the contact finish could make the connector susceptible to corrosion by exposing the base metal after repeated thermal cycling. Wear was assumed to be induced due to insufficient contact pressure between the electrical contacts. An alternative design was examined using finite element analysis which appears to provide a high contact load which should result in a lower contact resistance and less wear.

Describes a three‐dimensional machine vision technology for inspecting and measuring on‐line production. States that the 4DI three‐dimensional imager, a new machine vision technology developed by Intelligent Automation Systems, combines speed and accuracy to perform 100 per cent on‐line inspection and measurement of volumes and surfaces in real‐time. Until recently, neither conventional measurement techniques such as co‐ordinate measurement machines nor non‐contact optical technologies could inspect 100 per cent of production on‐line three‐dimensionally, being either too slow or too sensitive to ambient light. The 4DI uses structured laser light, multiple cameras and triangulation to capture moving or stationary objects. States this technology allows objects of different sizes, ranging from several feet to fractions of an inch to be imaged. States the system has no moving parts, it is robust in industrial environments.

This paper aims to develop a climbing robot to help people inspect lamps of high-mast lighting.

The robot consists of driving mechanism, suspension mechanism and compression mechanism. The driving mechanism is realized by link chains and sprockets, which are arranged opposite to each other, to form a dual caterpillar mechanism. The compression mechanism squeezes the caterpillar, and rubber feet “grasps” the steel rope to generate enough adhesion forces. The suspension mechanism is used to compensate the contraction or extension of the chains. The robot is equipped with a DC motor with a rated power of 250 W and a wireless module to communicate with the operator’s console. The dynamic model of the robot and the control strategy is derived, and the stability of the controller is proofed.

The payload experiment shows the robot can afford up to 3.7 times payload versus its own weight. Even when the payload is 30 kg, the robot can maintain a speed of the 1 m/s. The experiments also show that the tracking error of the robot reaches zero.

The proposed moving mechanism has a high load/weight ratio, which is a verified solution for the cable inspection purpose.

A rope climbing robot for high mast lighting inspection is proposed. The developed mechanism can reach a speed of 1 m/s with the payload of 30 kg, while its own weight is only 15.6 kg. The payload/weight ratio of the robot is 2.24; this value is rather good in many climbing robots reported in other renowned journal.