Measurement and Control

Amin, Arslan Ahmed; Mahmood-ul-Hasan, Khalid

doi: 10.1177/0020294018823031pmid: N/A

Fault-tolerant control systems are utilized in safety and critical applications to achieve greater reliability and availability for continued operation despite faults in the system components. These systems can be utilized in the process plants to avoid costly production loss due to abnormal and unscheduled tripping of the machines. In this paper, advanced fault-tolerant control systems of active type are proposed for air–fuel ratio control of internal combustion gas engine in a process plant to achieve greater reliability and availability to avoid a shutdown of the gas engine. Gas engines are extensively used equipment in the process industry and proper air–fuel ratio control in the fuel system of these engines is quite important to achieve greater engine efficiency, fuel energy savings and environmental protection. Active fault-tolerant control system is proposed in this paper in which linear regression–based observer model is used in the fault detection and isolation unit for fault detection, isolation and reconfiguration. Fuel actuator is introduced in the fuel supply line and proportional feedback controller is implemented to maintain the air–fuel ratio in faulty conditions. Redundancy in the sensors and fuel actuator is proposed to avoid engine shutdown in case of simultaneous faults in more than one sensor and to avoid a single point of failure due to fault in the single actuator. Noise is introduced in the sensor measurements to determine the robustness of proposed active fault-tolerant control system in noisy and faulty conditions. Results show that the proposed system remains stable, maintaining air–fuel ratio well in faulty conditions and is robust to noise.

Park, Joonhyuk; Shin, Yujeong; Hur, Hyunmoo; You, Wonhee

doi: 10.1177/0020294018819539pmid: N/A

Background:Active lateral suspension (ALS) technologies have been well developed for several decades, but they have not been widely used in service operation due to relatively high costs for implementation and maintenance and concerns about fail-safe. Therefore, this paper suggests a more practical approach for the active suspension system, designed to achieve target performance with easy implementation and maintenance and high fail-safe.Methods:The control performance target and actuator type are determined from the vibration energy that the ALS has to absorb along the weight function for ride quality evaluation. The installation position of actuator and sensor is decided to decrease the time that it takes for field engineers to check the actuator for maintenance. In addition to fail-safe function of ALS system, conventional hydraulic lateral damper is installed in parallel with ALS to reduce the concern about fail-safe of the ALS.Results:Through the roller rig and filed tests, the performance of the proposed ALS was validated. Lateral ride quality was improved 7.1dB and 6.7dB in the roller rig test and field test, respectively. The fail-safe strategy was also verified during the filed test.Conclusion:Test results show that the suggested ALS is designed appropriately and can be used in practical implementation.

Kilikevicius, Arturas; Fursenko, Antanas; Jurevicius, Mindaugas; Kilikeviciene, Kristina; Bureika, Gintautas

doi: 10.1177/0020294019836123pmid: N/A

The durability and endurance of the exploitation of railway bridges depend on the intensity and the manner of the static and dynamic loads affecting them. Heavy freight trains passing the bridges cause huge vertical and dual-axis vibrations, which are evidenced by the fatigue of the construction of the bridge. The scatter of the acceleration intensity of the railway bridge vibratory oscillation and their parameters are analysed while applying the theory of covariation functions. The results of the measurements of the intensity of the acceleration of vibratory oscillation in the points of support beams recorded in the timescale in the form of arrays (matrixes). Applied covariance function method provides measurement equipment and experimental simplicity of the analysis of the railway bridge vibration signals. The standard scores of mutual covariation functions of the array of the measurement results of the acceleration of digital vibratory oscillation and the standard scores of the auto-covariance functions of separate arrays are altering considering the interval of quantization in the timescale. Results gained by analysis prove the advantage of the rationed auto-covariational functions method while analysing the dynamic oscillation of bridges.

Zhang, Chengyang; Jing, Xishuang; Chen, Siyu; Ling, Xuanzhe; Zou, Jiarong; Zhao, Gang

doi: 10.1177/0020294018813644pmid: N/A

Background: When performing the spatial large-scale measurements, the measurement accuracy of laser tracker would decreased with the increase of the measurement distances due to the refraction difference of most optical digital measurement devices. Therefore, this paper proposed a method based on photogrammetry system to improve the large-scale measurement accuracy of the laser tracker. Purpose: The purpose of this method is to improve the large-scale measurement accuracy of the laser tracker by considering the advantages of photogrammetry system such as high measurement accuracy and good portability. Methods: The measurement data from the photogrammetry system would be used as a reference to do correction on measurement results from laser tracker. The coordinate correction method based on Rodrigues’ rotation formula has been discussed. The measurement accuracy of the long-distance point of laser tracker can be significantly improved through the coordinate correction method. Conclusion: Based on the advantages of using photogrammetry system, the proposed method can achieve higher accuracy when measuring the common points at a closer distance than the laser tracker can do when measuring objects far away from instrument. The feasibility of the proposed method has been demonstrated by experiment.

Guzmán-Rabasa, Julio Alberto; López-Estrada, Francisco Ronay; González-Contreras, Brian Manuel; Valencia-Palomo, Guillermo; Chadli, Mohammed; Pérez-Patricio, Madain

doi: 10.1177/0020294018824764pmid: N/A

This paper presents the design of a fault detection and diagnosis system for a quadrotor unmanned aerial vehicle under partial or total actuator fault. In order to control the quadrotor, the dynamic system is divided in two subsystems driven by the translational and the rotational dynamics, where the rotational subsystem is based on a linear parameter-varying model. A robust linear parameter-varying observer applied to the rotational subsystem is considered to detect actuator faults, which can occur as total failures (loss of a propeller or a motor) or partial faults (degradation). Furthermore, fault diagnosis is done by analyzing the displacements of the roll and pitch angles. Numerical experiments are carried out in order to illustrate the effectiveness of the proposed methodology.

Samraj, Dhas Bensam; Perumal, Maruthu Pandi

doi: 10.1177/0020294019858183pmid: N/A

In this paper, a comparative study between the two generator types with wind energy conversion system is proposed. The two generator types are doubly fed induction generators and permanent magnet synchronous generators. As in the wind turbine context, doubly fed induction generators and permanent magnet synchronous generators seem to be attractive solutions to be used to harness the wind energy. Wind turbine generators compatibility is anticipated in view of the stochastic nature of wind profile in the particular location in correlation with the Electro-Magnetic Torque profile of the wind generator which is acquired by simulating wind energy conversion system for the available wind speeds with high efficient generators. To validate the advantage of the proposed system, the torque profile of doubly fed induction generators and permanent magnet synchronous generators with an hourly average wind speed for 24-h time period is analysed. The real and reactive power of permanent magnet synchronous generators at wind speed of 13 m/s and permanent magnet synchronous generators increased pole pairs at wind speed of 13 m/s are also analysed. Furthermore, the power delivered by doubly fed induction generators and permanent magnet synchronous generators is analysed and compared. The comparison results demonstrate that the superiority of the permanent magnet synchronous generators over doubly fed induction generators and confirm its potential to extract the maximum energy from the wind.

Tiwari, Abhishek Kumar; Kumar, Amit; Kumar, Navin; Prakash, Chander

doi: 10.1177/0020294019858107pmid: N/A

Residual stresses are induced in the material during manufacturing operations, which considerably affect the fatigue performance and the lifespan of a mechanical work piece. The nature, magnitude, and distribution of residual stresses decide their beneficial or detrimental effects. Past research efforts concluded that mechanical process parameters influence residual stress nature, distribution, and the magnitude. Nevertheless, how residual stress generation depends on the process parameters, is not well investigated especially in the case of a drilling operation. In fact, the residual stress field is required to be regulated near drilled holes to improve the fatigue strength of structural joints, especially in the aircraft industry. Accordingly, this work attempts to estimate the drilling-induced micro-residual stress distribution near the drilled hole. In addition, the effect of drilling speed on residual stress distribution has also been studied. A nanoindentation technique is used to follow-up precise distribution of micro-residual stresses near the holes drilled at three different drilling speeds of 700, 900, and 1100 r/min. The outcomes indicate the presence of compressive residual stresses near the hole. In addition, an increase in residual stress level is noticed with an increase in the drilling speed up to 900 r/min. A uniform distribution of residual stresses is observed near the hole when drilled at a higher drilling speed of 1100 r/min. These findings may be useful in planning an improved drilling operation to produce beneficial residual stress distribution. This may ultimately improve the fatigue strength and the service life of mechanical components or structures with drilled holes.

Al-Mashhadani, Mohammad Abdulrahman

doi: 10.1177/0020294019866860pmid: N/A

In the past decade, many approaches that attempted to solve the problem of optimal control and parameter estimation of an unmanned aerial vehicle with a priori uncertain parameters simply implied two ways to solve such problem. First, by the formation of optimal control based on a refined mathematical model of the unmanned aerial vehicle, and second, by using the estimation and identification methods of the model parameter of the unmanned aerial vehicle based on measured data from flight tests. However, the identification of the dynamic parameters of the unmanned aerial vehicle is a complicated task because of a number of factors such as random vibration noise, disturbance, and uncertainty of the sensor measurements. Due to the influence of random vibration noise, the problem of correlated vibration noises and uncertainty has encountered inevitably, and the accuracy of the state estimation for unmanned aerial vehicle is degraded. This study concentrates on the optimal control and state estimation for the unmanned aerial vehicle under the combination of both random vibration noise and uncertainty collected by the sensors. The effects of random vibrations at various stages of a large-scale flight that are a priori uncertain require the inclusion of identification algorithms in the optimal control loop. The results showed that the method used in the analysis had been able to provide accurate estimations.

Nguyen, Duc Nam; Chau, Ngoc Le; Dao, Thanh-Phong; Prakash, Chander; Singh, Sunpreet

doi: 10.1177/0020294019864395pmid: N/A

The surface quality and accuracy of the geometry of the cylindrical rollers are important factors for bearing life. This paper presents effects of machining parameters on the surface roughness, topography and roundness of cylindrical rollers through the lapping and polishing experiments. And then the surface roughness of the cylindrical rollers is optimized. The results found that the surface roughness of rollers is significantly changed in lapping process with different abrasive particle sizes, while the surface roughness has slightly reduced in polishing process. It also indicated that the smoother surfaces with better roughness can be obtained after lapping and polishing process. In addition, the surface roughness of cylindrical rollers is rapidly reduced from Ra of 0.5 µm to Ra of 0.063 µm after the 3-h lapping process and Ra of 0.013 µm after the 1-h polishing process. The surface topography of rollers can be achieved by the smoother surface when loads are from 25 to 35 N in lapping process, and the loads are from 35 to 40 N in polishing process. Finally, the Taguchi method is applied to optimize the surface roughness in polishing process. The result found that the optimal surface roughness achieves 0.015 µm with respect to the time of 35 min and type of 4000# Al2O3.

Li-an, Zhao; Tieli, Wang; Wenqiang, Han

doi: 10.1177/0020294019864402pmid: N/A

Velocity distribution of vertical pipes with large particle slurry plays an important role in pipeline transportation of minerals in hydraulic coal mining and ocean mining industry. The experiments of particle fluidization and particle vertical lift are conducted and the fluidization data of three kinds of large particles are analyzed. The results show that the vortex resistance prevents particles from moving as the coarse particles move in vertical pipes. An additional coefficient method is proposed to study the vortex resistance by increasing the coefficient of vortex resistance before interference. Mathematical model is established to describe the drag coefficient of the vortex by analyzing the influence factors of the experimental data and the drag coefficient of the vortex. In addition, calculation model of the velocity distribution of large particles in vertical pipe is proposed by analyzing the force, the fluid, and the solid momentum. Moreover, the experimental data of particle transport in vertical pipes are utilized to verify and analyze the proposed model.