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Gabriel Lodewijks - One of the best experts on this subject based on the ideXlab platform.

  • Determining stress cycles for belt Conveyor Speed control in transient operations
    2016 IEEE International Conference on Service Operations and Logistics and Informatics (SOLI), 2016
    Co-Authors: Yusong Pang, Gabriel Lodewijks
    Abstract:

    Belt Conveyors are important equipment for large-scale bulk material transport and logistic distribution in very wide industry fields. In line with the variance of material loading degree, belt Conveyor Speed control has been proved as an effective way to reduce power consumption and to improve the service of the equipment with respect to system lifetime and maintenance. Since discrete control is preferred to regulate the Speed of Conveyor, control methods based on fuzzy logic can be applied. However, Speed control is not always applicable for all Conveyor operation scenarios. The stress cycles generated during fuzzy Speed control in transient operations may lead to extra degradation of the equipment and should be limited. This paper presents the determination of the stress cycles during the fuzzy control for belt Conveyor transient operations. After categorizing the loading scenarios that can be normally found in different application fields, the outputs of modeling and simulating a fuzzy Speed control system display the effect of stress cycles on belt Conveyor operations. The determination of minimum stress cycles along with maximum energy savings can be used to improve the algorithm and settings of belt Conveyor Speed control systems.

  • Belt Conveyor Dynamics in Transient Operation for Speed Control
    Journal of Civil and Environmental Engineering, 2016
    Co-Authors: Yusong Pang, Gabriel Lodewijks
    Abstract:

    Belt Conveyors play an important role in continuous dry bulk material transport, especially at the mining industry. Speed control is expected to reduce the energy consumption of belt Conveyors. Transient operation is the operation of increasing or decreasing Conveyor Speed for Speed control. According to literature review, current research rarely takes the Conveyor dynamics in transient operation into account. However, in belt Conveyor Speed control, the Conveyor dynamic behaviors are significantly important since the poor dynamics might result in risks. In this paper, the potential risks in transient operation will be analyzed. An existing finite element model will be applied to build a Conveyor model, and simulations will be carried out to analyze the Conveyor dynamics. In order to realize the soft Speed regulation, Harrison’s sinusoid acceleration profile will be applied, and Lodewijks estimator will be built to approximate the required acceleration time. A long inclined belt Conveyor will be studied with two major simulations. The Conveyor dynamics will be given.

  • Determination of Acceleration for Belt Conveyor Speed Control in Transient Operation
    International journal of engineering and technology, 2016
    Co-Authors: Yusong Pang, Gabriel Lodewijks
    Abstract:

    Speed control has been found a feasible mean to reduce the energy consumption of belt Conveyors. However, the current research has not taken the determination of the acceleration in transient operation into account sufficiently. With respect to the belt tension rating, demanded safety factor and the ratio between belt tension before and after drive pulley, this paper presents an approach to estimate the acceleration time. Case with specific horizontal belt Conveyor is studied. The simulations with finite element model are carried out to analyze the belt dynamic behaviors in transient operation. Further simulations are carried out to get the optimum acceleration time.

  • improving energy efficiency in material transport systems by fuzzy Speed control
    3rd IEEE International Symposium on Logistics and Industrial Informatics, 2011
    Co-Authors: Yusong Pang, Gabriel Lodewijks
    Abstract:

    Belt Conveyors are widely applied for industrial material transport and logistics distribution. In general, belt Conveyors run at nominal belt Speed. The belt can be only partly filled when received material flow is smaller than the nominal conveying capacity. Researches have shown that Conveyor Speed control always leads to the reduction of the required electrical drive power. Current applications mainly focus on developing control models and implementing controllers for continuous Speed adjustment. However, for practical reasons discrete control is preferred. This paper presents a fuzzy control method to improve the energy efficiency in material transport. This method applies fuzzy logic to represent the alteration of material flow scenarios. Fuzzy control algorithm provides optimal adjustment of belt Speed to avoid potential material spillage and overload caused by short-term peaks of material loading rate. The improvement of energy efficiency is estimated by both simulation and practical measurement.

J.k.l. Lai - One of the best experts on this subject based on the ideXlab platform.

  • Aging studies of PBGA solder joints reflowed at different Conveyor Speeds
    IEEE Transactions on Advanced Packaging, 2001
    Co-Authors: S.h. Fan, Y.c. Chan, C.w. Tang, J.k.l. Lai
    Abstract:

    In this paper, the shear cycle fatigue properties of plastic ball grid array (PBGA) assemblies' solder joints reflowed with three different profiles, and aged at 125/spl deg/C for four, nine, 16, 25, and 36 days are studied. The profiles were devised to have the same "heating factor," which was defined as the integral of the measured temperature above the liquidus (183/spl deg/C) with respect to dwell time in the reflow profile, but to have different Conveyor Speeds. The effects of Conveyor Speed on the solder joint (nonaged and aged) fatigue lifetimes were investigated. It was found hat with increasing the Conveyor Speed the solder joint shear fatigue lifetime could be improved substantially. Also, the shear fatigue lifetimes of aged solder joints decreased with increasing aging time and variation in fatigue lifetimes increased for faster Conveyor Speed. SEM and optical micrographs show that faster cooling rate caused a rougher interface of solder/IMC and less crystallization microstructure in solder joints. Rougher interface solder joints have a longer nonaged fatigue life. The thickness of IMC increases with increasing aging time and the growth rate for solder with faster cooling rate was larger. SEM cross section views reveal that cracks initiated at the acute position near the solder pad, then propagated along the interface of the bulk solder/IMC layer. Thicker IMC layers deteriorated fatigue life, so the fatigue lifetime variation of aged solder joints with fast cooling rate was larger.

  • Aging studies of PBGA solder joints reflowed at different Conveyor Speeds
    2000 Proceedings. 50th Electronic Components and Technology Conference (Cat. No.00CH37070), 1
    Co-Authors: S.h. Fan, Y.c. Chan, C.w. Tang, J.k.l. Lai
    Abstract:

    PBGA packages are more susceptible to solder joint fatigue problem due to the significant mismatches of the coefficient of thermal expansion (CTE) between bismaleimide triazine substrate (/spl sim/15 ppm//spl deg/C) and silicon die (/spl sim/2.5 ppm//spl deg/C). In this paper, the shear cycle fatigue properties of PBGA (Topline DC169) solder joints reflowed with different profiles, and aged at 125/spl deg/C for 4, 9, 16, 25, and 36 days are studied. The profiles are devised to have the same "heating factor", which is defined as the integral of the measured temperature above the liquidus (183/spl deg/C) with respect to dwell time in the reflow profile, but to have different Conveyor Speeds. The effects of Conveyor Speed on the solder joint (non-aged and aged) fatigue lifetimes are investigated.

Yusong Pang - One of the best experts on this subject based on the ideXlab platform.

  • Determining stress cycles for belt Conveyor Speed control in transient operations
    2016 IEEE International Conference on Service Operations and Logistics and Informatics (SOLI), 2016
    Co-Authors: Yusong Pang, Gabriel Lodewijks
    Abstract:

    Belt Conveyors are important equipment for large-scale bulk material transport and logistic distribution in very wide industry fields. In line with the variance of material loading degree, belt Conveyor Speed control has been proved as an effective way to reduce power consumption and to improve the service of the equipment with respect to system lifetime and maintenance. Since discrete control is preferred to regulate the Speed of Conveyor, control methods based on fuzzy logic can be applied. However, Speed control is not always applicable for all Conveyor operation scenarios. The stress cycles generated during fuzzy Speed control in transient operations may lead to extra degradation of the equipment and should be limited. This paper presents the determination of the stress cycles during the fuzzy control for belt Conveyor transient operations. After categorizing the loading scenarios that can be normally found in different application fields, the outputs of modeling and simulating a fuzzy Speed control system display the effect of stress cycles on belt Conveyor operations. The determination of minimum stress cycles along with maximum energy savings can be used to improve the algorithm and settings of belt Conveyor Speed control systems.

  • Belt Conveyor Dynamics in Transient Operation for Speed Control
    Journal of Civil and Environmental Engineering, 2016
    Co-Authors: Yusong Pang, Gabriel Lodewijks
    Abstract:

    Belt Conveyors play an important role in continuous dry bulk material transport, especially at the mining industry. Speed control is expected to reduce the energy consumption of belt Conveyors. Transient operation is the operation of increasing or decreasing Conveyor Speed for Speed control. According to literature review, current research rarely takes the Conveyor dynamics in transient operation into account. However, in belt Conveyor Speed control, the Conveyor dynamic behaviors are significantly important since the poor dynamics might result in risks. In this paper, the potential risks in transient operation will be analyzed. An existing finite element model will be applied to build a Conveyor model, and simulations will be carried out to analyze the Conveyor dynamics. In order to realize the soft Speed regulation, Harrison’s sinusoid acceleration profile will be applied, and Lodewijks estimator will be built to approximate the required acceleration time. A long inclined belt Conveyor will be studied with two major simulations. The Conveyor dynamics will be given.

  • Determination of Acceleration for Belt Conveyor Speed Control in Transient Operation
    International journal of engineering and technology, 2016
    Co-Authors: Yusong Pang, Gabriel Lodewijks
    Abstract:

    Speed control has been found a feasible mean to reduce the energy consumption of belt Conveyors. However, the current research has not taken the determination of the acceleration in transient operation into account sufficiently. With respect to the belt tension rating, demanded safety factor and the ratio between belt tension before and after drive pulley, this paper presents an approach to estimate the acceleration time. Case with specific horizontal belt Conveyor is studied. The simulations with finite element model are carried out to analyze the belt dynamic behaviors in transient operation. Further simulations are carried out to get the optimum acceleration time.

  • improving energy efficiency in material transport systems by fuzzy Speed control
    3rd IEEE International Symposium on Logistics and Industrial Informatics, 2011
    Co-Authors: Yusong Pang, Gabriel Lodewijks
    Abstract:

    Belt Conveyors are widely applied for industrial material transport and logistics distribution. In general, belt Conveyors run at nominal belt Speed. The belt can be only partly filled when received material flow is smaller than the nominal conveying capacity. Researches have shown that Conveyor Speed control always leads to the reduction of the required electrical drive power. Current applications mainly focus on developing control models and implementing controllers for continuous Speed adjustment. However, for practical reasons discrete control is preferred. This paper presents a fuzzy control method to improve the energy efficiency in material transport. This method applies fuzzy logic to represent the alteration of material flow scenarios. Fuzzy control algorithm provides optimal adjustment of belt Speed to avoid potential material spillage and overload caused by short-term peaks of material loading rate. The improvement of energy efficiency is estimated by both simulation and practical measurement.

Y.c. Chan - One of the best experts on this subject based on the ideXlab platform.

  • Aging studies of PBGA solder joints reflowed at different Conveyor Speeds
    IEEE Transactions on Advanced Packaging, 2001
    Co-Authors: S.h. Fan, Y.c. Chan, C.w. Tang, J.k.l. Lai
    Abstract:

    In this paper, the shear cycle fatigue properties of plastic ball grid array (PBGA) assemblies' solder joints reflowed with three different profiles, and aged at 125/spl deg/C for four, nine, 16, 25, and 36 days are studied. The profiles were devised to have the same "heating factor," which was defined as the integral of the measured temperature above the liquidus (183/spl deg/C) with respect to dwell time in the reflow profile, but to have different Conveyor Speeds. The effects of Conveyor Speed on the solder joint (nonaged and aged) fatigue lifetimes were investigated. It was found hat with increasing the Conveyor Speed the solder joint shear fatigue lifetime could be improved substantially. Also, the shear fatigue lifetimes of aged solder joints decreased with increasing aging time and variation in fatigue lifetimes increased for faster Conveyor Speed. SEM and optical micrographs show that faster cooling rate caused a rougher interface of solder/IMC and less crystallization microstructure in solder joints. Rougher interface solder joints have a longer nonaged fatigue life. The thickness of IMC increases with increasing aging time and the growth rate for solder with faster cooling rate was larger. SEM cross section views reveal that cracks initiated at the acute position near the solder pad, then propagated along the interface of the bulk solder/IMC layer. Thicker IMC layers deteriorated fatigue life, so the fatigue lifetime variation of aged solder joints with fast cooling rate was larger.

  • Fatigue Lifetimes of PBGA Solder Joints Reflowed at Different Conveyor Speeds
    Journal of Electronic Packaging, 1999
    Co-Authors: Y.c. Chan
    Abstract:

    The shear cycle fatigue lifetimes of plastic ball grid array (PBGA) solder joints formed using different reflow profiles are studied in this paper. The profiles were devised to have the same “heating factor” but to have different Conveyor Speeds. The test results show that, by increasing the Conveyor Speed during reflow, the shear fatigue lifetime of solder joints can be improved substantially. On the other hand, the fatigue lifetime of the test specimens decreased with increasing the cycle displacement amplitude. Heat transmission analysis shows that increasing Conveyor Speed increases the cooling rate during solder solidification. SEM micrographs reveal that cracks initiated at the acute point near the PCB solder pad, then propagate along the interface of the bulk solder/IMC layer. The test results are ascribed to roughing interface of the bulk solder/IMC of the solder joints that results on increasing the cooling rate. The frictional sliding mechanism is used to explain the test results.

  • Aging studies of PBGA solder joints reflowed at different Conveyor Speeds
    2000 Proceedings. 50th Electronic Components and Technology Conference (Cat. No.00CH37070), 1
    Co-Authors: S.h. Fan, Y.c. Chan, C.w. Tang, J.k.l. Lai
    Abstract:

    PBGA packages are more susceptible to solder joint fatigue problem due to the significant mismatches of the coefficient of thermal expansion (CTE) between bismaleimide triazine substrate (/spl sim/15 ppm//spl deg/C) and silicon die (/spl sim/2.5 ppm//spl deg/C). In this paper, the shear cycle fatigue properties of PBGA (Topline DC169) solder joints reflowed with different profiles, and aged at 125/spl deg/C for 4, 9, 16, 25, and 36 days are studied. The profiles are devised to have the same "heating factor", which is defined as the integral of the measured temperature above the liquidus (183/spl deg/C) with respect to dwell time in the reflow profile, but to have different Conveyor Speeds. The effects of Conveyor Speed on the solder joint (non-aged and aged) fatigue lifetimes are investigated.

B.h. Lee - One of the best experts on this subject based on the ideXlab platform.

  • Dynamic control of a robot manipulator for high-performance Conveyor tracking
    Journal of Robotic Systems, 1995
    Co-Authors: Tae-hyoung Park, B.h. Lee
    Abstract:

    A new robot control scheme for the specific application to Conveyor tracking is presented. To improve the performance of Conveyor tracking, the robot arm dynamics is incorporated into the control scheme. The tracking problem for the workpiece on a variable-Speed Conveyor is formulated as a stochastic optimal tracking problem with specified criteria. Dividing the Conveyor Speed into the nominal term and the perturbed term, a two-stage control strategy is employed to cope with the nonlinearity and uncertainty of the robot-Conveyor system. Simulation results are given to verify the good tracking performance with fast cycle time and high accuracy obtained in a robotic workcell. © 1995 John Wiley & Sons, Inc.

  • Two-stage control approach of a robot manipulator for Conveyor tracking application
    Proceedings of IECON'94 - 20th Annual Conference of IEEE Industrial Electronics, 1
    Co-Authors: Tae-hyoung Park, B.h. Lee, Il Hong Suh
    Abstract:

    A robot control scheme for the specific application to Conveyor tracking is newly proposed. To improve the performance of Conveyor tracking, the robot arm dynamics is incorporated into the control scheme. The proposed scheme also takes the torque and smoothness constraints into account for optimal Conveyor-tracking. Dividing the Conveyor Speed into the nominal term and the perturbed term, a two-stage control strategy is employed to cope with the nonlinearity and uncertainty of the robot-Conveyor system. >