Segment Erector Research Articles

Synchronization Control of a Dual-Cylinder Lifting Gantry of Segment Erector in Shield Tunneling Machine under Unbalance Loads

Segment assembling is one of the principle processes during tunnel construction using shield tunneling machines. The segment erector is a robotic manipulator powered by a hydraulic system to assemble prefabricated concrete segments onto the excavated tunnel surface. Nowadays, automation of the segment erector has become one of the definite developing trends to further improve the efficiency and safety during construction; thus, closed-loop motion control is an essential technology. Within the segment erector, the lifting gantry is driven by dual cylinders to lift heavy segments in the radial direction. Different from the dual-cylinder mechanism used in other machines such as forklifts, the lifting gantry usually works at an inclined angle, leading to unbalanced loads on the two sides. Although strong guide rails are applied to ensure synchronization, the gantry still occasionally suffers from chattering, “pull-and-drag”, or even being stuck in practice. Therefore, precise motion tracking control as well as high-level synchronization of the dual cylinders have become essential for the lifting gantry. In this study, a complete dynamics model of the dual-cylinder lifting gantry is constructed, considering the linear motion as well as the additional rotational motion of the crossbeam, which reveals the essence of poor synchronization. Then, a two-level synchronization control scheme is synthesized. The thrust allocation is designed to coordinate the dual cylinders and keep the rotational angle of the crossbeam within a small range. The motion tracking controller is designed based on the adaptive robust control theory to guarantee the linear motion tracking precision. The theoretical performance is analyzed with corresponding proof. Finally, comparative simulations are conducted and the results show that the proposed scheme achieves high-precision motion tracking performance and simultaneous high-level synchronization of dual cylinders under unbalanced loads.

Requirement Acquisition Method of Product Life cycle Based on HLDA Hierarchy Model under the Background of Web Technology

Product requirement is the goal of product development and design activities, which originates from all stages of product life cycle. In the process of acquiring product requirements, there are some problems such as incomplete mining of product requirements and fuzzy structural expression. In view of the above problems, this paper proposes a product life cycle requirements acquisition method based on axiomatic design. Firstly, web technology is applied to collect requirements information, and based on HLDA hierarchy model, the requirements information is classified according to the whole life cycle stages of products; then, the product requirements mining model based on axiomatic design is established to mine the requirements of the whole product life cycle; finally, the product requirements model tree is structured and the product life cycle requirement model is established; This paper takes shield machine segment erector as an example to verify the effectiveness of the proposed product life cycle requirements acquisition method.

Development and simulation of magnetorheological damper for segment erector vibration control

In this paper, magnetorheological dampers are applied to a segment erector to replace passive vibration dampers. Because magnetorheological damper dynamics are highly nonlinear, design of a direct control system is impossible. To apply linear control theory directly to design the magnetorheological damper controller, the Takagi–Sugeno fuzzy model analytically represents the segment erector model. In addition, a disturbance observer based on a Takagi–Sugeno fuzzy controller is proposed for this system. Both simulations and experiments validate the performance enhancement and stability of the controller. The results show that the acceleration of the segment erector was reduced by 59.6% and 32.1% in oblique wave excitation and random excitation, respectively, compared to a conventional passive damper. The proposed fuzzy controller and magnetorheological dampers have great potential in practical applications because they can significantly improve the performance of a segment erector.

Electro-hydraulic control of high-speed segment erection processes

Abstract To improve the efficiency of constructing a tunnel lining, an effective high-speed segment erection system is desired. Due to the excessive positioning errors and large joint forces caused by high speed and large inertia loads, a conventional segment erector is unable to achieve a high-speed erection process. To reduce the steady-state positioning error of a segment erector under high-speed working conditions, this work presents a speed and position compound control system (SPCS) based on the electro-hydraulic proportional control technology. A combined motion law with a smooth and continuous changing speed is adopted for the erecting motion to reduce joint force. Experiments are carried out on a Φ2.2 m segment erector test rig to evaluate the performances of the designed control system. Experimental results show that the SPCS is superior to the position feedback control system (PFCS) in terms of accuracy and joint force under high-speed working conditions. The maximum rotation speed of the erector with the SPCS can reach up to thrice that of the conventional segment erection system without decreasing the positioning precision and increasing the joint force. To further increase the segment erecting efficiency, a parallel speed and position compound control system (PSPCS) with multi-axis simultaneous movements is proposed. The coupling effects of the three positioning motions are analyzed. According to the experimental results, the time consumed by the erection system with PSPCS on the segment positioning process is further reduced to approximate one third of that by the erection system with SPCS.

Energy saving analysis of segment positioning in shield tunneling machine considering assembling path optimization

A motion parameter optimization method based on the objective of minimizing the total energy consumption in segment positioning was proposed for segment erector of shield tunneling machine. The segment positioning process was decomposed into rotation, lifting and sliding actions in deriving the energy calculation model of segment erection. The work of gravity was taken into account in the mathematical modeling of energy consumed by each actuator. In order to investigate the relationship between the work done by the actuator and the path moved along by the segment, the upward and downward directions as well as the operating quadrant of the segment erector were defined. Piecewise nonlinear function of energy was presented, of which the result is determined by closely coupled components as working parameters and some intermediate variables. Finally, the effectiveness of the optimization method was proved by conducting a case study with a segment erector for the tunnel with a diameter of 3 m and drawing comparisons between different assembling paths. The results show that the energy required by assembling a ring of segments along the optimized moving path can be reduced up to 5%. The method proposed in this work definitely provides an effective energy saving solution for shield tunneling machine.

Paralleling Hydraulic Control of Variable Frequency Motor and Valve for the Swing Mechanism of Segment Erector

Aimed at achieving a high speed and precision circumferential positioning of pipe under low energy consumption, a paralleling hydraulic control of variable frequency motor and valve (PHC-VFMV) system is designed for the swing mechanism of segment erector. Firstly, with a view to the working principle of the swing mechanism, a hydraulic circuit of the PHC-VFMV is designed. Then, two sub-circuits of the hydraulic circuit are separately modeled and equipped with suitable controllers. Finally, one valve control (VC) system and the designed PHC-VFMV system are tested in AMEsim platform. Results show that, while guaranteeing a good performance of speed and accuracy, the PHC-VFMV could achieve a better performance in energy saving than VC.

The Development of a High-Speed Segment Erecting System for Shield Tunneling Machine

The present study is focused on developing an effective high-speed segment erecting system, which is specific for modern shield tunneling machine. The big steady-state error and large impact force caused by high motion speed and large inertia load are main restrictions for the conventional segment erector to realize high-speed segment erecting. To overcome the bottleneck, a new hydraulic system that is based on electrohydraulic proportional control technology is designed, the actuator speed of which is adjustable and controllable. The kinematic and dynamic models are established to determine the displacement of each actuator and calculate joint force, respectively. A combined motion law is then selected to reduce joint force during acceleration and deceleration stages. Furthermore, a superior control strategy that is able to precisely and smoothly control the segment erector at high speed is chosen by comparing the experimental performances of four different control strategies. Experiments are carried out on a segment erector test rig. The experimental results show exceptional performances of the speed and position compound control system in terms of accuracy and impact force. The maximum rotation speed of the new system can be increased to more than three times of that of the present erecting system. In addition, high steady-state accuracy can be achieved with the new system while its impact force is just about one-third of the position control system.

Innovative group-decoupling design of a segment erector based on G F set theory

The segment erector is a key part of the shield machines for tunnel engineering. The available segment erectors are all of serial configuration which is suffering from the problems of low rigidity and accumulative motion errors. The current research mainly focuses on improving assembly accuracy and control performance of serial segment erectors. An innovative design method is proposed featuring motion group-decoupling, based on which a new type of segment erector is developed and investigated. Firstly, the segment installation manipulation is analyzed and decomposed into three motion groups that are decoupled. Then the type synthesis for the 4-DOF motion group is performed based on the general function(G F ) set theory and a new configuration of (1T⊕1R⊕1PS&3UPS) is attained according to the segment manipulation requirements. Consequently, the kinematic models are built and the reducibility and accuracy are analyzed. The dexterity is verified though numerical simulation and no singular points appear in the workspace. Finally, a positioning experiment is carried out by using the prototype developed in the lab that demonstrates a 13.1% improvement of positioning accuracy and the feasibility of the new segment erector. The presented group-decoupling design method is able to invent new type of hybrid segment erectors that avoid the accumulative motion error of erecting.

Building of Fine-Tuning Mechanism Posture and Kinematics Model for Shield Segment Erector

The fine-tuning posture 3-SPS-1-S-type mechanism’s kinematics model and position mechanism for segment erector is built by creating general stiffness motion and revolution motion’s posture parameterized representations based on the Lie groupoids theory’s kinematic synthesis, the duality between parallel mechanism structure and performance and PRY angle coordination system’s kinematics analysis.

Orientation capability of PS-3-SPS-type parallel robot with application in segment erector

Orientation capability is investigated for a new design of PS-3-SPS parallel robot using for segment erector. Kinematics, reachable workspace, and orientation capability are modelled. Rotation angular range of moving platform with respect to different axes is analysed. Simulations show when the length of a sub-chain is shortened, the moving platform can reach more space but rotation capability becomes limited when lengths grow to a certain range, rotation capability increases sharply while reachable area greatly reduced. Case studies demonstrate the PS-3-SPS mechanism has great characteristics. Our research lays the foundation for motion planning and control of this mechanism.

Research of Dynamics Simulation of a Six-DOF Segment Erector for Tunnel Boring Machine

In order to solve the problems such as more restriction conditions, complicated interference and longer design periods in the design process of segment erector for Tunnel Boring Machine, it is necessary to study on the dynamics simulation of TBM segment erector. The 3D virtual assembling model of a tunnel segment erector is built based on Pro/E software according to its design parameters such as structure and size. The model is simplified and optimized reasonably and various constraints are applied under variety working conditions. The dynamics characteristics of drives and the forces of each part are obtained and they will provide a boundary condition for strength check and basis for the power system design which is important for the further optimal design. The simulation results also provide an important reference for the mechanism design and type selection design for the power system of segment erector and design cycle is shortened for TBM segment erector.

Dynamics Simulation of a Six-DOF Tunnel Segment Erector for Tunnel Boring Machine Based on Virtual Prototype

In this paper, we present the modeling and dynamics simulation of a six-DOF tunnel segment erector for tunnel boring machine (TBM), which is performed in the virtual prototype platform. The 3D virtual assembling model of a tunnel segment erector is built based on Pro/E software according to its design parameters such as structure and size. After the interference inspection, the model is imported into ADAMS through the interface module of Mech/Pro. The model is simplified and optimized reasonably and various constraints are applied under variety working conditions. The results of simulation show that the design has six degrees of freedom movement capacity which meets the design requirements. At the same time the dynamics characteristics of drives and the forces of each part are obtained and they will provide a boundary condition for strength check and basis for the power system design which is important for the further optimal design.

Research of Kinematics Simulation of TBM Segment Erector Based on Virtual Prototype

In order to solve the problems such as more restriction conditions, complicated interference and longer design periods in the design process of segment erector for Tunnel Boring Machine, it is necessary to study on the kinematics simulation of TBM segment erector. First of all, the kinematics characteristics of segment erector are analyzed; the 3-D model is designed in Pro/E environment; the model is imported into ADAMS and the dynamic simulation is finished finally. After the analysis of simulation of this mechanism, the curves of the speed for the driving parts are obtained and the maximum speeds of driving parts are identified with the method of space search technology. The kinematics characteristics of TBM segment erector are obtained. The simulation results provide an important reference for the mechanism design and type selection design for the power system and design cycle is shortened for TBM segment erector.

Virtual Prototype Simulation of Fine-Adjustment System Kinematics for Segment Erector of Tunnel Boring Machine

In this paper, we present the modeling and kinematics simulation of fine-adjustment system for segment erector of tunnel boring machine (TBM), which is performed in the virtual prototype platform. The 3D virtual assembling model of fine-adjustment system is built with Pro/E software according to its design parameters such as structure and size. After the interference inspection, the model is imported into ADAMS through the interface module of Mech/Pro. The model is simplified and optimized reasonably and various constraints are applied under variety working conditions. The results of simulation show that the design has three degrees of freedom movement capacity which meets the design requirements. At the same time the kinematics characteristics of each part along three different directions are obtained and they will provide some references for the further optimal design.

Modeling and Kinematics Simulation of a Six-DOF Segment Erector for Tunnel Boring Machine Based on Virtual Prototype

In this paper, we present the modeling and kinematics simulation of a six-DOF segment erector for tunnel boring machine (TBM), which is performed in the virtual prototype platform. The 3D virtual assembling model of a tunnel segment erector is built based on Pro/E software according to its design parameters such as structure and size. After the interference inspection, the model is imported into ADAMS through the interface module of Mech/Pro. The model is simplified and optimized reasonably and various constraints are applied under variety working conditions. The results of simulation show that the design has six degrees of freedom movement capacity which meets the design requirements. At the same time the kinematics characteristics of each part along three different directions are obtained and they will provide some references for the further optimal design.

Simulation and Research on Double Cylinder Hydraulic System Synchronized Control for Segment Erector of TBM

This paper analyzes reasons for non-synchronization of double cylinders of segment erector of TBM and puts forward feasible synchronized control proposal. Meanwhile, mathematical modeling is built and AMEsim software is used for simulation of synchronized and coordinated control of lifting system of segment erector. The simulation results show that synchronized control accuracy meeting the design requirements.TBM (tunnel boring machine) is a large-sized hydromechatronics engineering device in modern tunnel works, and segment erector is its key component. Research on double cylinders of hydraulic system of segment erector of TBM is carried out in this paper, and AMEsim software is used to simulate the synchronized and coordinated control of lifting system of segment erector.

A redundantly actuated PRPRP radial mechanism in the segment erector of a shield machine for synchronization control

The shield machine is a heavy construction machine for tunnel excavation, and the segment erector is an important subsystem of the shield machine. It is difficult to achieve precise control in the 6-DOF (degree of freedom) erector in the 2-DOF 5-bar radial mechanism. Hence, this paper proposes a redundantly actuated PRPRP radial mechanism for the segment erector. When the redundant actuator is unlocked, the radial mechanism is able to adjust its posture, which has two degrees of freedom. On the other hand, when the redundant actuator is locked or produces enough pre-tightening tensile force, the PRPRP mechanism can ensure the synchronization of the two driving hydraulic cylinders along the radial direction based on the mechanical structure, which has one degree of freedom. The redundant actuator also facilitates the equal application of two flexural torques at the hydraulic cylinders; thus, preventing the overload of a single cylinder.

Drive system design and error analysis of the 6 degrees of freedom segment erector of shield tunneling machine

Focusing on a segment erector of a shield-tunneling machine developed with 6 degrees of freedom (DOF) and controlled by electro-hydraulic proportional systems, the kinematics of the segment erection process is presented. The perturbation method in the error analysis is introduced to establish the position and attitude error model, considering a number of factors such as the hydraulic drive, control accuracy, and tolerance in manufacturing and assembly. Dynamic simulations are carried out to obtain the controlling precision of electrohydraulic drive systems. Formulas for calculating the position and attitude error of the grip hand of the segment erector are derived. The calculation results verify the practicality and effectiveness of the error analysis, providing a foundation for practical designing, manufacturing, and assembling of the segment of the erecting mechanism.

Research on simulation of tunnel boring machine based on virtual prototype

Technology of digital mockup is introduced and the application background and practical requirement of tunnel boring machine has been discussed in this paper. One type of EPB tunnel boring machine's virtual prototype has been built. Software PROE is used to build the tunnel boring machine model. Application program of virtual assembly system base on virtual reality is developed by using division. The author also study on key technologies of constructing virtual assembly system of tunnel boring machine, such as interference detection in virtual environment. The result shows that the work station can be simulated well, and this virtual simulation system can be extended in virtual training and manipulation, virtual construction and so on. And finite element analysis of some critical components is operated. Structure strength checking which can provide support for the optimal design of segment erector has been made.

力・変位制御を応用したセグメントの組立に関する基礎研究

Usually segments are set up by a segment erector which is controlled manually. Recently a few segment erectors which can be controlled automatically have been developed to minimize the set up time. In the automated erectors, segment displacement is controlled, that is, a segment is hauled and fitted to the existing segments controlling the displacement. By this method, it is well known that the very accurate control is necessary.This results in a comparatively expensive control system and also very careful maintenance schedule.In this paper, the authors discussed on an applicability of control method where a linear combination of force and displacement is chosen as the control variable. By this method, segment is controlled as the conventional displacement control method as far as the segment is not contacted to the existing segments. However, after the contact, force is taken into consideration as the control variable and excessive force is minimized.The computer simulation revealed that by this control method, a segment is hauled and fitted to existing segment smoothly. Also small scale model experiment is carried out successfully and the results support the calculated one.