The system translates the arm/boom/buck's potential energy into electrical energy and then the electrical energy is stored in a storage device.This study develops a set of energy management strategy to make the re...The system translates the arm/boom/buck's potential energy into electrical energy and then the electrical energy is stored in a storage device.This study develops a set of energy management strategy to make the recoverable energy recycling efficiently.This energy of traditional excavator is lost in the form of heat energy,which is wasteful,and makes the component's temperature higher and higher to reduce the machine's life.Research on this system not only conforms to the current topic of energy crisis,but also mates with the actual engineering,so it is significant to research that.展开更多
Though the traditional energy regeneration system(ERS) which used a hydraulic motor and a generator in hybrid excavators can regenerate part of the energy, the power of the motor and the generator should be larger a...Though the traditional energy regeneration system(ERS) which used a hydraulic motor and a generator in hybrid excavators can regenerate part of the energy, the power of the motor and the generator should be larger and the time for regenerating energy is so short. At first, the structure of new ERS that combines the advantages of an electric and hydraulic accumulator is analyzed. The energy can be converted into both the electric energy and the hydraulic energy at the lowering of the boom and the generator can still works when the boom stops going down. Then, a method how to set the working pressure of the hydraulic accumulator is proposed. To avoid the excess loss, extra noise and shock pressure, a two-level pressure threshold method that the generator starts to work at the rising edge of the high pressure threshold and stops working at the falling edge of the low pressure threshold is presented to characterize the working mode of the generator. The control strategies on how to control the boom velocity at the lowering of the boom and how to improve the recovery efficiency when the boom stops going down are presented. The test bench of hybrid excavator with ERS is constructed, with which the studies on the influences of ERS on energy conversion efficiency and control performance are carried out. Experimental results show that the proposed ERS features better speed control performance of the boom than traditional ERS. It is also observed that an estimated 45% of the total potential energy could be regenerated at the lowering of the boom in the proposed ERS, and the power level of the generator and the hydraulic motor could be reduced by 60%. Hence, the proposed ERS has obvious advantages over the traditional ERS on the improvement of energy regeneration time, energy efficiency, control performance and economy.展开更多
The hydraulic excavator energy-saving research mainly embodies the following three measures: to improve the performance of diesel engine and hydraulic component, to improve the hydraulic system, and to improve the po...The hydraulic excavator energy-saving research mainly embodies the following three measures: to improve the performance of diesel engine and hydraulic component, to improve the hydraulic system, and to improve the power matching of diesel-hydraulic system-actuator. Although the above measures have certain energy-saving effect, but because the hydraulic excavator load changes frequently and fluctuates dramatically, so the diesel engine often works in high-speed and light load condition, and the fuel consumption is higher. Therefore, in order to improve the economy of diesel engine in light load, and reduce the fuel consumption of hydraulic excavator, energy management concept is proposed based on diesel engine cylinder deactivation technology. By comparing the universal characteristic under diesel normal and deactivated cylinder condition, the mechanism that fuel consumption can be reduced significantly by adopting cylinder deactivation technology under part of loads condition can be clarified. The simulation models for hydraulic system and diesel engine are established by using AMESim software, and fuel combustion consumption by using cylinder-deactivation-technology is studied through digital simulation approach. In this way, the zone of cylinder deactivation is specified. The testing system for the excavator with this technology is set up based on simulated results, and the results show that the diesel engine can still work at high efficiency with part of loads after adopting this technology; fuel consumption is dropped down to 11% and 13% under economic and heavy-load mode respectively under the condition of driving requirements. The research provides references to the energy-saving study of the hydraulic excavators.展开更多
Mobile machinery energy efficiency and emission pollution are the national and worldwide issues. This paper contributes in solving these problems by applying a speed variable power source. Unfortunately, almost all of...Mobile machinery energy efficiency and emission pollution are the national and worldwide issues. This paper contributes in solving these problems by applying a speed variable power source. Unfortunately, almost all of the speed variable systems have the dynamic response problem when the motor starts with full load or heavy load. To address this problem, a hydraulic accumulator is used to balance the load of the power source for assisting starting of the motor and a matching method combined with speed and displacement control of the pump is proposed to improve the energy efficiency and dynamic performance simultaneously under different working conditions. Also, the power source/valve combined control strategy of an independent metering system is designed to realize flow matching of the whole system. Firstly, a test system is established to study the dynamic performance and energy efficiency of the speed variable power source with an auxiliary accumulator. Working performance and energy consumption of the power source under different rotating speeds and different loads are studied. And then, the hydraulic excavator test rig with the proposed system is constructed. Furthermore, the working performance of the excavator with the speed-fixed and speed-variable strategy are studied comparatively. Results show that, compared with fixed-speed strategy, the electric power consumption during the idle period and partial load condition can be reduced about 2.05 kW and 1.37 kW. The energy efficiency of speed variable power source is about 40%-71%, which is higher than that of the fixed-speed power source by 3%–10%.展开更多
Instead of establishing mathematical hydraulic system models from physical laws usually done with the problems of complex modelling processes, low reliability and practicality caused by large uncertainties, a novel mo...Instead of establishing mathematical hydraulic system models from physical laws usually done with the problems of complex modelling processes, low reliability and practicality caused by large uncertainties, a novel modelling method for a highly nonlinear system of a hydraulic excavator is presented. Based on the data collected in the excavator's arms driving experiments, a data-based excavator dynamic model using Simplified Refined Instrumental Variable (SRIV) identification and estimation algorithms is established. The validity of the proposed data-based model is indirectly demonstrated by the performance of computer simulation and the.real machine motion control exoeriments.展开更多
An electro-hydraulic control system is designed and implemented for a robotic excavator known as the Lancaster University Computerised and Intelligent Excavator (LUCIE). The excavator is being developed to autonomou...An electro-hydraulic control system is designed and implemented for a robotic excavator known as the Lancaster University Computerised and Intelligent Excavator (LUCIE). The excavator is being developed to autonomously dig trenches without human intervention. Since the behavior of the excavator arm is dominated by the nonlinear dynamics of the hydraulic actuators and by the large and unpredictable external disturbances when digging, it is difficult to provide adequate accurate, quick and smooth movement under traditional control methodology, e.g., PI/PID, which is comparable with that of an average human operator. The data-based dynamic models are developed utilizing the simplified refined instrumental variable (SRIV) identification algorithm to precisely describe the nonlinear dynamical behaviour of the electro-hydraulic actuation system. Based on data-based model and proportional-integral-plus (PIP) methodology, which is a non-minimal state space method of control system design based on the true digital control (TDC) system design philosophy, a novel control system is introduced to drive the excavator arm accurately, quickly and smoothly along the desired path. The performance of simulation and field tests which drive the bucket along straight lines both demonstrate the feasibility and validity of the proposed control scheme.展开更多
Hydraulic excavator is one type of the most widely applied construction equipment for various applications mainly because of its versatility and mobility. Among the tasks performed by a hydraulic excavator, repeatable...Hydraulic excavator is one type of the most widely applied construction equipment for various applications mainly because of its versatility and mobility. Among the tasks performed by a hydraulic excavator, repeatable level digging or flat surface finishing may take a large percentage. Using automated functions to perform such repeatable and tedious jobs will not only greatly increase the overall productivity but more importantly also improve the operation safety. For the purpose of investigating the technology without loss of generality, this research is conducted to create a coordinate control method for the boom, arm and bucket cylinders on a hydraulic excavator to perform accurate and effective works. On the basis of the kinematic analysis of the excavator linkage system, the tip trajectory of the end-effector can be determined in terms of three hydraulic cylinders coordinated motion with a visualized method. The coordination of those hydraulic cylinders is realized by controlling three electro-hydraulic proportional valves coordinately. Therefore, the complex control algorithm of a hydraulic excavator can be simplified into coordinated motion control of three individual systems. This coordinate control algorithm was validated on a wheeled hydraulic excavator, and the validation results indicated that this developed control method could satisfactorily accomplish the auto-digging function for level digging or flat surface finishing.展开更多
This paper presents the results of an on-going project and investigates modelling and remote control issues of an industry excavator. The details of modelling, communication, and control of a remotely controllable exc...This paper presents the results of an on-going project and investigates modelling and remote control issues of an industry excavator. The details of modelling, communication, and control of a remotely controllable excavator are studied. The paper mainly focuses on trajectory tracking control of the excavator base and robust control of the excavator arm. These will provide the fundamental base for our next research step. In addition, extensive simulation results for trajectory tracking of the excavator base and robust control of the excavator arm are given. Finally, conclusions and further work have been identified.展开更多
Limitations of various accumulators in hybrid hydraulic excavator are analyzed. A program using capacitor as the accumulator based on constant work-point control is put forward. A simulating experimental system of hyb...Limitations of various accumulators in hybrid hydraulic excavator are analyzed. A program using capacitor as the accumulator based on constant work-point control is put forward. A simulating experimental system of hybrid construction machinery is established, and experimental study on constant work-point control for parallel hybrid system with capacitor accumulator is carried out using the pressure and flow rate derived from boom cylinder of hydraulic excavator in actual work as the simulating loads. A program of double work-point control is proposed and proved by further experiments.展开更多
Based on reference[1], the Automatic Control System of the Excavating Process (ACSEP) is studied and aualyzed In this paper- At first, the general structure of the control system is discussed- And theo depeded on the ...Based on reference[1], the Automatic Control System of the Excavating Process (ACSEP) is studied and aualyzed In this paper- At first, the general structure of the control system is discussed- And theo depeded on the kinematical equations, the "Generator or Expected link variable (GE)" and "Generator of Actual bucket trajectory (CA)" are put forward. Finally, based on the current technology and existing techniques of WD-400 Mechanical Forward Excavator (MFE), the automatic system of excavating process composed of two relatively indepodent sub-systems is designed with simple but practical structure’ According to the computer simulation, this control system has high tracking precision to the desired trajectory and good adaptive capacity to the load disturbance.展开更多
Within this paper, the process of statistical safety analysis has been presented, which involves the following steps: formulation of basic principles of statistical safety analysis, initial events analysis, accident ...Within this paper, the process of statistical safety analysis has been presented, which involves the following steps: formulation of basic principles of statistical safety analysis, initial events analysis, accident sceneries progress analysis, risk calculation, and risk calculation results analysis. On this basis, it has been concluded that the bucket wheel excavator SRs 1200×24/4×0(400 kW)+VR safety criteria is the mechanism for the hoist of rotor's arrow failure modes, because in that case whole bucket wheel excavator failure would necessarily happen (excavator falling down on counterweight). Therefore, excavator units statistical safety analysis is accomplished preventively to obtain its effective maintenance management.展开更多
An adaptive sliding mode control system for the excavator manipulator during straight line digging operation was presented in this paper.The adaptive laws derived from Lyapunov stability theorem were used to update sw...An adaptive sliding mode control system for the excavator manipulator during straight line digging operation was presented in this paper.The adaptive laws derived from Lyapunov stability theorem were used to update switching gains and compensate uncertainties.The dynamic model of the excavator manipulator considering link shape and weight was established and the straight line trajectory of the bucket tooth tip of excavator was transformed into the desired joint angle trajectory for direct control.Finally,simulation results showed the superiority of the proposed control scheme compared with traditional variable structure control with sliding mode.展开更多
In consideration of the uncertainty of basic events failure rate and lack of probability statistical information in fault tree analysis( FTA) of excavator variable-frequency speed control system, the interval theory w...In consideration of the uncertainty of basic events failure rate and lack of probability statistical information in fault tree analysis( FTA) of excavator variable-frequency speed control system, the interval theory was employed and combined with conventional FTA method. The basic events failure probabilities were described by interval numbers,and the interval operators of logical gates in FTA were deduced based on interval theory. Finally,the reliability assessment of excavator variable-frequency speed control system was done by interval FTA method. The result shows that the interval FTA method is suitable for the complex system with insufficient failure data.展开更多
In the design of large mining excavator electrical system,a practical reliability allocation method was introduced to allocate system level reliability requirements into subsystem and component levels. During the reli...In the design of large mining excavator electrical system,a practical reliability allocation method was introduced to allocate system level reliability requirements into subsystem and component levels. During the reliability allocation process,factors from the fault and maintenance data were only considered in reliability allocation scheme. It could avoid the disturbance from expert experiences. The entropy method was also used to obtain weights of reliability allocation indexes of large mining excavators considering different factors. Then the failure rate allocation of subsystems and components could be completed.展开更多
Visual tracking has been widely applied in construction industry and attracted signifi-cant interests recently. Lots of research studies have adopted visual tracking techniques on the surveillance of construction work...Visual tracking has been widely applied in construction industry and attracted signifi-cant interests recently. Lots of research studies have adopted visual tracking techniques on the surveillance of construction workforce, project productivity and construction safety. Until now, visual tracking algorithms have gained promising performance when tracking un-articulated equipment in construction sites. However, state-of-art tracking algorithms have unguaranteed performance in tracking articulated equipment, such as backhoes and excavators. The stretching buckets and booms are the main obstacles of successfully tracking articulated equipment. In order to fill this knowledge gap, the part-based tracking algorithms are introduced in this paper for tracking articulated equipment in construction sites. The part-based tracking is able to track different parts of target equipment while using multiple tracking algorithms at the same sequence. Some existing tracking methods have been chosen according to their outstanding performance in the computer vision community. Then, the part-based algorithms were created on the basis of selected visual tracking methods and tested by real construction sequences. In this way, the tracking performance was evaluated from effectiveness and robustness aspects. Throughout the quantification analysis, the tracking performance of articulated equipment was much more improved by using the part-based tracking algorithms.展开更多
In order to shorten the design cycle of the excavator working device, we have proposed a rapid modeling method for the excavator working device which uses parameters. Based on the Pro/toolkit, which is secondary devel...In order to shorten the design cycle of the excavator working device, we have proposed a rapid modeling method for the excavator working device which uses parameters. Based on the Pro/toolkit, which is secondary development tool of Pro/E4.0,and combined with Vs C++2005 programming software. It developed a flexible set of MFC visualization-friendly interfaces. Users can enter data in the visual interface according to their needs and it will generate a new part model quickly. So it improves the design quality, shortens the design cycle, and makes the cost lower significantly.展开更多
To improve the energy efficiency of a hydraulic boom, a new energy-saving system adopting a hydraulic accumulator is proposed. First, the principle of the system is presented. Then, the dynamic simulation is intro- du...To improve the energy efficiency of a hydraulic boom, a new energy-saving system adopting a hydraulic accumulator is proposed. First, the principle of the system is presented. Then, the dynamic simulation is intro- duced. Finally, the conclusions are given based on the analysis of simulation data. In Summary, the innovative energy-saving system combines flow regeneration and potential energy recovery, runs steadily and comfortably, saves energy remarkably and has good potential for improving energy utilization of a hydraulic excavator.展开更多
Research on intelligent and robotic excavator has become a focus both at home and abroad, and this type of excavator becomes more and more important in application. In this paper, we developed a control system which c...Research on intelligent and robotic excavator has become a focus both at home and abroad, and this type of excavator becomes more and more important in application. In this paper, we developed a control system which can make the intelligent robotic excavator perform excavating operation autonomously. It can recognize the excavating targets by itself, program the operation automatically based on the original parameter, and finish all the tasks. Experimental results indicate the validity in real-time performance and precision of the control system. The intelligent robotic excavator can remarkably ease the labor intensity and enhance the working efficiency.展开更多
The energy saving of hydraulic excavators is always an essential research.An energy recovery system can effectively recover the boom potential energy and rotational kinetic energy.Based on the standard working cycle o...The energy saving of hydraulic excavators is always an essential research.An energy recovery system can effectively recover the boom potential energy and rotational kinetic energy.Based on the standard working cycle of hydraulic excavators,a dynamic programming(DP)control strategy for hybrid hydraulic excavators was proposed to recover the boom potential energy and rotational kinetic energy.The hybrid hydraulic excavator simulation model was built by Simulink software.The simulation results indicated that the fuel consumption of hybrid hydraulic excavators using the DP control strategy was about 21.3%lower than that of the conventional hydraulic excavator.In order to experimentally verify the simulation results,an experimental platform for hybrid hydraulic excavators was built.The experimental results indicated that the fuel consumption of hybrid hydraulic excavators using the DP control strategy was about 18.9%lower than that of the conventional hydraulic excavator.This paper shows that the DP control strategy applied to hybrid hydraulic excavators can recycle the boom potential energy and rotational kinetic energy,and reduce the fuel consumption of hybrid hydraulic excavators.展开更多
Recently,the application of Bayesian updating to predict excavation-induced deformation has proven successful and improved prediction accuracy significantly.However,updating the ground settlement profile,which is cruc...Recently,the application of Bayesian updating to predict excavation-induced deformation has proven successful and improved prediction accuracy significantly.However,updating the ground settlement profile,which is crucial for determining potential damage to nearby infrastructures,has received limited attention.To address this,this paper proposes a physics-guided simplified model combined with a Bayesian updating framework to accurately predict the ground settlement profile.The advantage of this model is that it eliminates the need for complex finite element modeling and makes the updating framework user-friendly.Furthermore,the model is physically interpretable,which can provide valuable references for construction adjustments.The effectiveness of the proposed method is demonstrated through two field case studies,showing that it can yield satisfactory predictions for the settlement profile.展开更多
基金supported by Science and Technology Research and Development Plan Project of Handan City(22422401138ZC)2022 School Level Project in Handan University(XZ2022203)。
文摘The system translates the arm/boom/buck's potential energy into electrical energy and then the electrical energy is stored in a storage device.This study develops a set of energy management strategy to make the recoverable energy recycling efficiently.This energy of traditional excavator is lost in the form of heat energy,which is wasteful,and makes the component's temperature higher and higher to reduce the machine's life.Research on this system not only conforms to the current topic of energy crisis,but also mates with the actual engineering,so it is significant to research that.
基金supported by National Natural Science Foundation of China(Grant No. 50875233)National Hi-tech Research and Development Program of China(863 Program, Grant No. 2010AA044401)+3 种基金Open Fund of the State Key Lab of Flow Power Transmission and Control(Grant No. GZKF-201111)National Youth Science Foundofion of China(Grant No. 51205140)Fundamental Research Funds for the Central University of China(Grant No. JB-ZR1208)Scientific Research Funds of Huaqiao University, China(Grant No. 11BS409)
文摘Though the traditional energy regeneration system(ERS) which used a hydraulic motor and a generator in hybrid excavators can regenerate part of the energy, the power of the motor and the generator should be larger and the time for regenerating energy is so short. At first, the structure of new ERS that combines the advantages of an electric and hydraulic accumulator is analyzed. The energy can be converted into both the electric energy and the hydraulic energy at the lowering of the boom and the generator can still works when the boom stops going down. Then, a method how to set the working pressure of the hydraulic accumulator is proposed. To avoid the excess loss, extra noise and shock pressure, a two-level pressure threshold method that the generator starts to work at the rising edge of the high pressure threshold and stops working at the falling edge of the low pressure threshold is presented to characterize the working mode of the generator. The control strategies on how to control the boom velocity at the lowering of the boom and how to improve the recovery efficiency when the boom stops going down are presented. The test bench of hybrid excavator with ERS is constructed, with which the studies on the influences of ERS on energy conversion efficiency and control performance are carried out. Experimental results show that the proposed ERS features better speed control performance of the boom than traditional ERS. It is also observed that an estimated 45% of the total potential energy could be regenerated at the lowering of the boom in the proposed ERS, and the power level of the generator and the hydraulic motor could be reduced by 60%. Hence, the proposed ERS has obvious advantages over the traditional ERS on the improvement of energy regeneration time, energy efficiency, control performance and economy.
基金supported by National Hi-tech Research and Development Program of China (863 Program, Grant No. 2010AA044401)
文摘The hydraulic excavator energy-saving research mainly embodies the following three measures: to improve the performance of diesel engine and hydraulic component, to improve the hydraulic system, and to improve the power matching of diesel-hydraulic system-actuator. Although the above measures have certain energy-saving effect, but because the hydraulic excavator load changes frequently and fluctuates dramatically, so the diesel engine often works in high-speed and light load condition, and the fuel consumption is higher. Therefore, in order to improve the economy of diesel engine in light load, and reduce the fuel consumption of hydraulic excavator, energy management concept is proposed based on diesel engine cylinder deactivation technology. By comparing the universal characteristic under diesel normal and deactivated cylinder condition, the mechanism that fuel consumption can be reduced significantly by adopting cylinder deactivation technology under part of loads condition can be clarified. The simulation models for hydraulic system and diesel engine are established by using AMESim software, and fuel combustion consumption by using cylinder-deactivation-technology is studied through digital simulation approach. In this way, the zone of cylinder deactivation is specified. The testing system for the excavator with this technology is set up based on simulated results, and the results show that the diesel engine can still work at high efficiency with part of loads after adopting this technology; fuel consumption is dropped down to 11% and 13% under economic and heavy-load mode respectively under the condition of driving requirements. The research provides references to the energy-saving study of the hydraulic excavators.
基金Supported by National Natural Science Foundation of China(Grant Nos.51575374,U1510206)
文摘Mobile machinery energy efficiency and emission pollution are the national and worldwide issues. This paper contributes in solving these problems by applying a speed variable power source. Unfortunately, almost all of the speed variable systems have the dynamic response problem when the motor starts with full load or heavy load. To address this problem, a hydraulic accumulator is used to balance the load of the power source for assisting starting of the motor and a matching method combined with speed and displacement control of the pump is proposed to improve the energy efficiency and dynamic performance simultaneously under different working conditions. Also, the power source/valve combined control strategy of an independent metering system is designed to realize flow matching of the whole system. Firstly, a test system is established to study the dynamic performance and energy efficiency of the speed variable power source with an auxiliary accumulator. Working performance and energy consumption of the power source under different rotating speeds and different loads are studied. And then, the hydraulic excavator test rig with the proposed system is constructed. Furthermore, the working performance of the excavator with the speed-fixed and speed-variable strategy are studied comparatively. Results show that, compared with fixed-speed strategy, the electric power consumption during the idle period and partial load condition can be reduced about 2.05 kW and 1.37 kW. The energy efficiency of speed variable power source is about 40%-71%, which is higher than that of the fixed-speed power source by 3%–10%.
文摘Instead of establishing mathematical hydraulic system models from physical laws usually done with the problems of complex modelling processes, low reliability and practicality caused by large uncertainties, a novel modelling method for a highly nonlinear system of a hydraulic excavator is presented. Based on the data collected in the excavator's arms driving experiments, a data-based excavator dynamic model using Simplified Refined Instrumental Variable (SRIV) identification and estimation algorithms is established. The validity of the proposed data-based model is indirectly demonstrated by the performance of computer simulation and the.real machine motion control exoeriments.
基金supported by the Lancaster University (UK)SooChow University, China+2 种基金the UK Engineering and Physical Sciences Research CouncilUniversities’ Natural Science Research Council of Jiangsu Universities, China(Grant No. 08KJB510021)Scientific Research Foundation for the Returned Overseas Chinese Scholars, Ministry of Education of China
文摘An electro-hydraulic control system is designed and implemented for a robotic excavator known as the Lancaster University Computerised and Intelligent Excavator (LUCIE). The excavator is being developed to autonomously dig trenches without human intervention. Since the behavior of the excavator arm is dominated by the nonlinear dynamics of the hydraulic actuators and by the large and unpredictable external disturbances when digging, it is difficult to provide adequate accurate, quick and smooth movement under traditional control methodology, e.g., PI/PID, which is comparable with that of an average human operator. The data-based dynamic models are developed utilizing the simplified refined instrumental variable (SRIV) identification algorithm to precisely describe the nonlinear dynamical behaviour of the electro-hydraulic actuation system. Based on data-based model and proportional-integral-plus (PIP) methodology, which is a non-minimal state space method of control system design based on the true digital control (TDC) system design philosophy, a novel control system is introduced to drive the excavator arm accurately, quickly and smoothly along the desired path. The performance of simulation and field tests which drive the bucket along straight lines both demonstrate the feasibility and validity of the proposed control scheme.
基金supported by National Natural Science Foundation of China (Grant No. 50875228)
文摘Hydraulic excavator is one type of the most widely applied construction equipment for various applications mainly because of its versatility and mobility. Among the tasks performed by a hydraulic excavator, repeatable level digging or flat surface finishing may take a large percentage. Using automated functions to perform such repeatable and tedious jobs will not only greatly increase the overall productivity but more importantly also improve the operation safety. For the purpose of investigating the technology without loss of generality, this research is conducted to create a coordinate control method for the boom, arm and bucket cylinders on a hydraulic excavator to perform accurate and effective works. On the basis of the kinematic analysis of the excavator linkage system, the tip trajectory of the end-effector can be determined in terms of three hydraulic cylinders coordinated motion with a visualized method. The coordination of those hydraulic cylinders is realized by controlling three electro-hydraulic proportional valves coordinately. Therefore, the complex control algorithm of a hydraulic excavator can be simplified into coordinated motion control of three individual systems. This coordinate control algorithm was validated on a wheeled hydraulic excavator, and the validation results indicated that this developed control method could satisfactorily accomplish the auto-digging function for level digging or flat surface finishing.
文摘This paper presents the results of an on-going project and investigates modelling and remote control issues of an industry excavator. The details of modelling, communication, and control of a remotely controllable excavator are studied. The paper mainly focuses on trajectory tracking control of the excavator base and robust control of the excavator arm. These will provide the fundamental base for our next research step. In addition, extensive simulation results for trajectory tracking of the excavator base and robust control of the excavator arm are given. Finally, conclusions and further work have been identified.
文摘Limitations of various accumulators in hybrid hydraulic excavator are analyzed. A program using capacitor as the accumulator based on constant work-point control is put forward. A simulating experimental system of hybrid construction machinery is established, and experimental study on constant work-point control for parallel hybrid system with capacitor accumulator is carried out using the pressure and flow rate derived from boom cylinder of hydraulic excavator in actual work as the simulating loads. A program of double work-point control is proposed and proved by further experiments.
文摘Based on reference[1], the Automatic Control System of the Excavating Process (ACSEP) is studied and aualyzed In this paper- At first, the general structure of the control system is discussed- And theo depeded on the kinematical equations, the "Generator or Expected link variable (GE)" and "Generator of Actual bucket trajectory (CA)" are put forward. Finally, based on the current technology and existing techniques of WD-400 Mechanical Forward Excavator (MFE), the automatic system of excavating process composed of two relatively indepodent sub-systems is designed with simple but practical structure’ According to the computer simulation, this control system has high tracking precision to the desired trajectory and good adaptive capacity to the load disturbance.
文摘Within this paper, the process of statistical safety analysis has been presented, which involves the following steps: formulation of basic principles of statistical safety analysis, initial events analysis, accident sceneries progress analysis, risk calculation, and risk calculation results analysis. On this basis, it has been concluded that the bucket wheel excavator SRs 1200×24/4×0(400 kW)+VR safety criteria is the mechanism for the hoist of rotor's arrow failure modes, because in that case whole bucket wheel excavator failure would necessarily happen (excavator falling down on counterweight). Therefore, excavator units statistical safety analysis is accomplished preventively to obtain its effective maintenance management.
文摘An adaptive sliding mode control system for the excavator manipulator during straight line digging operation was presented in this paper.The adaptive laws derived from Lyapunov stability theorem were used to update switching gains and compensate uncertainties.The dynamic model of the excavator manipulator considering link shape and weight was established and the straight line trajectory of the bucket tooth tip of excavator was transformed into the desired joint angle trajectory for direct control.Finally,simulation results showed the superiority of the proposed control scheme compared with traditional variable structure control with sliding mode.
基金National High-Tech Research and Development Program(863 Program),China(No.2012AA062001)
文摘In consideration of the uncertainty of basic events failure rate and lack of probability statistical information in fault tree analysis( FTA) of excavator variable-frequency speed control system, the interval theory was employed and combined with conventional FTA method. The basic events failure probabilities were described by interval numbers,and the interval operators of logical gates in FTA were deduced based on interval theory. Finally,the reliability assessment of excavator variable-frequency speed control system was done by interval FTA method. The result shows that the interval FTA method is suitable for the complex system with insufficient failure data.
基金National High-Tech Research and Development Program(863 Program),China(No.2012AA062001)
文摘In the design of large mining excavator electrical system,a practical reliability allocation method was introduced to allocate system level reliability requirements into subsystem and component levels. During the reliability allocation process,factors from the fault and maintenance data were only considered in reliability allocation scheme. It could avoid the disturbance from expert experiences. The entropy method was also used to obtain weights of reliability allocation indexes of large mining excavators considering different factors. Then the failure rate allocation of subsystems and components could be completed.
文摘Visual tracking has been widely applied in construction industry and attracted signifi-cant interests recently. Lots of research studies have adopted visual tracking techniques on the surveillance of construction workforce, project productivity and construction safety. Until now, visual tracking algorithms have gained promising performance when tracking un-articulated equipment in construction sites. However, state-of-art tracking algorithms have unguaranteed performance in tracking articulated equipment, such as backhoes and excavators. The stretching buckets and booms are the main obstacles of successfully tracking articulated equipment. In order to fill this knowledge gap, the part-based tracking algorithms are introduced in this paper for tracking articulated equipment in construction sites. The part-based tracking is able to track different parts of target equipment while using multiple tracking algorithms at the same sequence. Some existing tracking methods have been chosen according to their outstanding performance in the computer vision community. Then, the part-based algorithms were created on the basis of selected visual tracking methods and tested by real construction sequences. In this way, the tracking performance was evaluated from effectiveness and robustness aspects. Throughout the quantification analysis, the tracking performance of articulated equipment was much more improved by using the part-based tracking algorithms.
文摘In order to shorten the design cycle of the excavator working device, we have proposed a rapid modeling method for the excavator working device which uses parameters. Based on the Pro/toolkit, which is secondary development tool of Pro/E4.0,and combined with Vs C++2005 programming software. It developed a flexible set of MFC visualization-friendly interfaces. Users can enter data in the visual interface according to their needs and it will generate a new part model quickly. So it improves the design quality, shortens the design cycle, and makes the cost lower significantly.
文摘To improve the energy efficiency of a hydraulic boom, a new energy-saving system adopting a hydraulic accumulator is proposed. First, the principle of the system is presented. Then, the dynamic simulation is intro- duced. Finally, the conclusions are given based on the analysis of simulation data. In Summary, the innovative energy-saving system combines flow regeneration and potential energy recovery, runs steadily and comfortably, saves energy remarkably and has good potential for improving energy utilization of a hydraulic excavator.
文摘Research on intelligent and robotic excavator has become a focus both at home and abroad, and this type of excavator becomes more and more important in application. In this paper, we developed a control system which can make the intelligent robotic excavator perform excavating operation autonomously. It can recognize the excavating targets by itself, program the operation automatically based on the original parameter, and finish all the tasks. Experimental results indicate the validity in real-time performance and precision of the control system. The intelligent robotic excavator can remarkably ease the labor intensity and enhance the working efficiency.
基金jointly sponsored by the National Key R&D Program of China(Grant No.2023YFC3010904)the National Key R&D Program of China(Grant No.2021YFC3002003)the Science and Technology Research and Major Achievement Transformation Project of Strategic Emerging Industries in Hunan Province(Grant No.2019GK4014).
文摘The energy saving of hydraulic excavators is always an essential research.An energy recovery system can effectively recover the boom potential energy and rotational kinetic energy.Based on the standard working cycle of hydraulic excavators,a dynamic programming(DP)control strategy for hybrid hydraulic excavators was proposed to recover the boom potential energy and rotational kinetic energy.The hybrid hydraulic excavator simulation model was built by Simulink software.The simulation results indicated that the fuel consumption of hybrid hydraulic excavators using the DP control strategy was about 21.3%lower than that of the conventional hydraulic excavator.In order to experimentally verify the simulation results,an experimental platform for hybrid hydraulic excavators was built.The experimental results indicated that the fuel consumption of hybrid hydraulic excavators using the DP control strategy was about 18.9%lower than that of the conventional hydraulic excavator.This paper shows that the DP control strategy applied to hybrid hydraulic excavators can recycle the boom potential energy and rotational kinetic energy,and reduce the fuel consumption of hybrid hydraulic excavators.
基金the financial support from the Guangdong Provincial Department of Science and Technology(Grant No.2022A0505030019)the Science and Technology Development Fund,Macao SAR,China(File Nos.0056/2023/RIB2 and SKL-IOTSC-2021-2023).
文摘Recently,the application of Bayesian updating to predict excavation-induced deformation has proven successful and improved prediction accuracy significantly.However,updating the ground settlement profile,which is crucial for determining potential damage to nearby infrastructures,has received limited attention.To address this,this paper proposes a physics-guided simplified model combined with a Bayesian updating framework to accurately predict the ground settlement profile.The advantage of this model is that it eliminates the need for complex finite element modeling and makes the updating framework user-friendly.Furthermore,the model is physically interpretable,which can provide valuable references for construction adjustments.The effectiveness of the proposed method is demonstrated through two field case studies,showing that it can yield satisfactory predictions for the settlement profile.