Huafeng Ding

• PhD
• Head of Department at China University of Geosciences

Shovel attachment is one of the most commonly used working attachments in hydraulic excavators. Its mechanical design remains a challenging optimization problem. To tackle this issue, the optimizing model of ordinary shovel attachment is firstly established which contains twenty-three design variables, six objective functions, and sixty-three const...

Tetrahedral mechanisms are mechanisms whose architectures constructed based on tetrahedron. Take the vertex as a ternary link, and the edge as a binary link respectively, the generalized mechanism is built. To describe the tetrahedral generalized mechanism, the topological graph is drawn and is expressed by configuration matrix. Possible types of t...

This paper is concerned with the fixed-time formation-containment control (FTFCC) problem for networked Euler-Lagrange systems (NELSs) with unknown dynamics and disturbances. A systematically adaptive control scheme is established to address the above problems. Specifically, to reduce controller update frequency and conserve resources, a novel FTFC...

The finite‐time nonlinear placement problem of networked Euler‐Lagrange systems (NELSs) is discussed in this paper. The problem is reformulated into a finite‐time aggregate game under an undirected graph. Then, several novel practical gradient‐based finite‐time hierarchical (GFTH) algorithms composed of a game layer, a Nash equilibrium (NE) seeking...

A novel compliant mechanism with RPR degrees of freedom (DOF) is proposed where R and P represent rotation and translation DOFs, respectively. The proposed compliant mechanism is obtained from dimension synthesizing a 2-RPU-UPR rigid parallel mechanism with the method of optimization of motion/force transfer characteristic. R, P and U represent rot...

Hydraulic shovel is widely used in mining industry around the world for materials excavation and loading. The mechanical design of hydraulic shovel remains a challenging optimization problem. To address this issue, we establish the many-objective optimization model of a new type hydraulic shovel named TriRocker. An improved reference points-based m...

This paper presents a novel six degree-of-freedom (6-DOF) parallel robot with only three identical limbs for high-speed operations. First, displacement analysis of the new parallel robot is performed, in which the closed-form forward displacement model can be obtained through a relatively concise derivation. Then, velocity and acceleration models o...

The creative design of mechanisms has been widely believed as one of the most important branches in the theory of mechanisms. Beside, the structural synthesis of kinematic chains (KCs) of mechanisms has been well-known as a fundamental technique for establishing novel theories towards intelligent design of mechanisms. This has thus motivated an inc...

A method for the automatic sketching of kinematic chains is presented. First, a layout algorithm based on the move of inner edges is proposed to determine the optimal layouts of topological graphs. Then, these topological graphs are automatically converted into the corresponding kinematic chains via a correction algorithm.

The topological models of planar kinematic chains with simple joints, multiple joints and geared joints are proposed and the relationships between these models are revealed.

Some fundamental concepts of graph theory that are necessary for the structurual analysis and synthesis of kinematic chains and mechanisms are introduced.

A systematic and fully automatic method based on parent graphs is presented to synthesize 1-DOF and non-fractionated 2-DOF PGTs. The complete database of rotation graphs and displacement graphs of 1-DOF and 2-DOF PGTs with up to nine links is established for the first time. Besides, all possible reasons for the contradictory synthesis results in th...

Based on the bicolor topological graph and its inter-convertible characteristics with that of simple joint kinematic chains, an automatic method is proposed to synthesize multiple joint kinematic chains from the atlas of simple joint kinematic chains. The whole family of multiple joint kinematic chains with up to 16 links is synthesized via this me...

A unified method called the loop superposition method is proposed to detect rigid sub-chains in simple and multiple joint kinematic chains and planetary gear trains.

Based on the structural synthesis and classified atlas databases of simple joint kinematic chains, multiple joint kinematic chains and planetary gear trains, a creative design method is proposed to obtain all the feasible mechanisms for a specified task from the topological graphs in the classified atlas databases subject to design constraints. Exa...

An automatic method is presented to generate non-isomorphic inversions from the atlas of planar non-fractionated simple joint kinematic chains. A complete set of inversions of planar non-fractionated simple joint kinematic chain with up to 19 links are automatically synthesized.

A new formula for the connectivity calculation between two links is proposed, based on which an automatic method to acquire the connectivity matrix for planar closed kinematic chains is developed. This method can be used to automatically generate the mechanisms whose base and end-effector have the required connectivity from the synthesized kinemati...

The relationships between the contracted graphs of planar kinematic chains are revealed first. Then a fully-automatic method is proposed to synthesize the whole family of contracted graphs for planar non-fractionated kinematic chains with all possible DOFs.

An automatic method is presented to synthesize planar kinematic chains with prismatic pairs. A new algorithm based on the parameters of degree, weight, degree-sequence and weight-sequence is developed to resolve the key isomorphism problem. Kinematic chains with prismatic pairs and with up to 14 links are synthesized.

A unified isomorphism detection method that is suitable for simple joint kinematic chains, mimple joint kinematic chains and planetary gear trains is developed.

An original loop algebra theory is proposed to analyze the topological structure of kinematic chains.

Based on the structure characteristics of fractionated kinematic chains, a general synthesis equation of planar fractionated kinematic chains is proposed first. Then an automatic method is proposed to synthesize planar fractionated kinematic chains by the combination of planar non-fractionated kinematic chains, and the whole family of planar fracti...

A general method is proposed to synthesize planar non-fractionated kinematic chains based on the atlas of contracted graphs. The method is fully-automatic and designer-friendly, and planar non-fractionated kinematic chains with up to 19 links are succesfully synthesized.

The singularity problem brings troubles to the design and application for the parallel mechanism. Currently, redundant actuation is one of the useful methods to solve this singularity problem. However, faced to the numerous joints in a parallel mechanism, how to make a quantitative criterion of seeking the most efficient joints added actuators for...

In this paper, an iterative learning control (ILC) method based on sliding mode technique is proposed for hybrid force/position control of robot manipulators. Different from traditional ILC, the main purpose of the proposed ILC is to learn the dynamic parameters rather than the control signals. The sliding mode technique is applied to enhance the r...

A 3-RRPRR variable spherical symmetrical parallel mechanism (PM) with arc-shaped sliding pairs and no parasitic motion is presented, exhibiting two rotational and one translational (2R1T) degrees of freedom. Three limbs are symmetrically distributed between the base and end-effector; upper and lower parts of each limb are mirror symmetrical around...

Both 1-DOF and multi-DOF planetary gear trains (PGTs) have extensive application in various kinds of mechanical equipment. However, the existing synthesis methods mainly focused on 1-DOF PGTs, while the research on the synthesis of multi-DOF PGTs is very limited. This paper presents an automatic method to synthesize non-fractionated 2-DOF PGTs, fre...

The number of synthesized kinematic chains usually is too large to evaluate individual characteristics of each chain. The concept of connectivity is useful to classify the kinematic chains. In this paper, an algorithm is developed to automatically compute the connectivity matrix in planar kinematic chains. The main work is to compute two intermedia...

A novel 2R1T (two rotational and one translational degrees-of-freedom) parallel spindle head (PSH) without parasitic motion is proposed which is based on the specific 3-UPU (P and U stand for prismatic joint and universal joint, respectively) parallel mechanism (PM). A modified virtual joint method (VJM) is proposed to solve the deformation analysi...

This paper focuses on a 2R1T 3-UPU (U for universal joint and P for prismatic joint) parallel mechanism (PM) with two rotational and one translational (2R1T) degrees of freedom (DOFs) and the ability of multiple remote centers of motion (M-RCM). The singularity analysis based on the indexes of motion/force transmissibility and constraint shows that...

In this paper, the distributed fixed-time formation-containment (DFTFC) problem of multiple Euler-Lagrange systems with parametric uncertainties and input disturbances is studied under directed graphs. First, a distributed fixed-time sliding-mode estimator is constructed to estimate the desired states of each robot with that only parts of followers...

The novel surface plasmon resonance (SPR) sensor based on hybrid structure of Ag-indium tin oxide (ITO)-blue phosphorene (BlueP)/transition metal dichalcogenides (TMDCs)-graphene is presented. The BlueP/TMDCs heterostructure works as an interacting layer with the analyte for the enhancement of the of the sensor’s sensitivity. For angular sensitivit...

The novel configuration of surface plasmon resonance (SPR) based on Ag-indium tin oxide (ITO)-transition metal dichalcogenides (TMDCs)-graphene hybrid structures is proposed for highly sensitivity biosensor. When the WS2 and graphene are 3 layers and monolayer, respectively, the highest angular sensitivity up to 213.2°/RIU is obtained. Moreover, se...

Current research of automatic transmission (AT) mainly focuses on the improvement of driving performance, and configuration innovation is one of the main research directions. However, finding new configurations of ATs is one of the main limitations of configuration innovation. In the present study, epicyclic gear trains (EGTs) are applied to invest...

The aim of this study is to present a novel shape-transformable polyhedral mechanism namely, the TrT–T mechanism, which can transform between a truncated tetrahedron and a common tetrahedron. The conceptual model of the TrT–T mechanism is proposed and described. For one-degree-of-freedom objective, a hexagonal planar linkage is chosen as a hexagona...

In order to improve the performance of surface plasmon resonance (SPR) biosensor, the structure based on two-dimensional (2D) of graphene and transition metal dichalcogenides (TMDCs) are proposed to greatly enhance the Goos-Hänchen (GH) shift. It is theoretically proved that GH shift can be significantly enhanced in SPR structure coated with gold (...

Surface plasmon resonance (SPR) biosensor is widely used for its high precision and real-time analysis. In this paper, SPR biosensor based on the hybrid structure of metal–indium tin oxide (ITO)–WS2 are proposed and investigated. By optimizing the thickness of metals (Au, Cu, Ag), ITO and WS2, the reflectivity of 2.932 × 10⁻⁷ a.u and highest phase...

The heterostructures of two-dimensional (2D) materials have broad application prospects in surface plasmon resonance (SPR) biosensor. In order to enhance the sensitivity, we propose new a configuration of SPR biosensor based on Cu/Au/Ag-indium tin oxide (ITO)-graphene/two-dimensional transition metal dichalcogenide (TMDC) hybrid structures for high...

Mechanisms that contain prismatic pairs (P-pairs) are widely used in industry. Synthesizing kinematic chains with P-pairs is a pivotal step in the conceptual design of mechanisms with P-pairs. However, most synthesis methods for plane kinematic chains in the literature focused on the chains with only revolute pairs (R-pairs), those chains with P-pa...

A novel spatial multi-loop coupled mechanism (SMCM) with a single translational mobility (1T) is proposed in the paper. The mechanism is different from traditional parallel mechanisms due to three coupled chains connected with branches. Three parts are obtained through separating the mechanism, and mobility analysis is given from the motion and con...

Space curve meshing theory is a new design theory for gearing mechanism, which is different from the principle of conjugate surface meshing. It transmits power and movement according to pairs of conjugated curves on the tooth profiles. According to conjugated curves, the driving and driven tooth profiles of the new meshing principle gears are const...

Planetary gear trains (PGTs) are widely used in transmission systems. The structural synthesis of PGTs is an effective way to create novel and excellent transmissions. In the structural synthesis of PGTs, the isomorphism detection (ID) is an essential and especially important process. The ID aims to avoid duplication and guarantee the uniqueness of...

The structural synthesis of planetary gear trains (PGTs) is helpful for innovating transmission systems in machinery. A great deal of research has been devoted to the synthesis of one-degree-of-freedom (1-DOF) PGTs over the past half century. However, most synthesis methods are limited to PGTs with no more than eight links. Moreover, the synthesis...

In this article, the design of a nonrelative sliding gear mechanism for parallel axes transmission is presented. First, the general meshing line functions were actively designed for the nonrelative sliding transmission between parallel axes. The parametric equations of contact curves on the driving and driven gears were deduced by the coordinate tr...

A novel type synthesis method for a class of spatial multi-loop coupled mechanisms with translational degrees of freedom is proposed in the paper. The novel class of spatial multi-loop coupled mechanisms has a stable topology layout which consists of three branches and three coupled chains. The basic idea of the new structural synthesis method lies...

A surface plasmon resonance (SPR)-based optical reflection modulator consisting of vertically stacked silica-silicon-HfO2-ITO-HfO2-Ag-prism multilayer is proposed and numerically investigated. The free carrier-concentration-dependent permittivity of indium-tin-oxide (ITO) at the HfO2/ITO interface induces an epsilon-near-zero (ENZ) effect contribut...

Turbodrill is an important type of drilling tool. Rotating speed is a key parameter to measure and control the efficiency of a turbodrill. Therefore, it is necessary to measure the rotating speed when a turbodrill is working under a well. However, current speed measurement devices and sensors cannot meet the requirements of the on-site downhole con...

This paper reports an novel method, opto-acousto-fluidic microscopy, for label free detection of droplets and cells in microfluidic networks. Leveraging the optoacoustic effect, the microscopic system possesses capabilities of visualizing...

Joint reaction solution of a mechanism is an important basis of its strength check, fatigue analysis and friction analysis. This paper presents a general method for solving all joint reactions of three-rotation and two-translation (3R2T) parallel mechanisms with complicated structures and multiple redundant constraints. First, joint reaction expres...

In the synthesis of kinematic chains, especially using computerized methods, the synthesis results are usually represented in the numerical form. Sketching the synthesis results as visual kinematic chains is helpful for the creative design of mechanisms. This paper proposes a new method for the automatic sketching of planar kinematic chains, by con...

The umbrella linkage is one of the most classical deployable mechanisms. This paper concentrates on topological structural design of a family of umbrella-shaped deployable mechanisms based on new two-layer and two-loop spatial linkage units. First, deployable units are developed systematically from two-layer and two-loop linkage with four revolute...

Coalbed methane (CBM) is one kind of clean-burning gas and has been valued as a new form of energy that will be used widely in the near future. When producing CBM, the working level within a CBM wellbore annulus needs to be monitored to dynamically adjust the gas drainage and extraction processes. However, the existing method of measuring the worki...

An autotracking algorithm based on a hybrid grey prediction model is presented for au- tonomously navigating the laparoscopic visual window of a robot-assisted surgical system. This method can be applied to any view angle of the three-dimensional (3D) laparoscope with a 200 ms predictive motion. Firstly, a preset parameter-based tracking algorithm...

A nanoscale structure which comprises metal-insulator-metal (MIM) waveguide, stub resonator, and hexagonal resonator is proposed to realize plasmon-induced transparency (PIT) response. The characteristics of the device are numerically investigated with different geometrical parameters. Benefitting from the narrow transparency window and long coupli...

This paper presents a general method for analyzing stiffness of overconstrained parallel robotic mechanisms with Scara motion. In the method, the stiffness model of a limb is derived by applying Castigliano's second theorem to strain energy of the limb with a structural decomposition strategy, and the stiffness matrix of a parallel mechanism is est...

Planetary gear trains (PGTs) are widely used in machinery to transmit angular velocity ratios or torque ratios. The graph theory has been proved to be an effective tool to synthesize and analyze PGTs. This paper aims to propose a new graph model, which has some merits relative to the existing ones, to represent the structure of PGTs. First, the rot...

This paper aims to construct a novel family of deployable mechanisms from a class of two-layer and two-loop spatial linkages, each of which consists of an eight revolute pair (8R) single-loop linkage connected by a 5R serial chain. First, structural characteristics of the class of linkages as deployable units are analyzed and illustrated. Then, the...

This paper presents a quick two-stage position control strategy based on a hybrid intelligent optimization algorithm for a planar n-link underactuated manipulator with a passive first joint. In stage 1, the system is directly reduced to a planar virtual Acrobot by controlling n-2 active links to their target angles. A hybrid intelligent optimizatio...

This paper presents an automatic method to synthesize mechanisms, namely inversions, from planar non-fractionated simple joint kinematic chains. First, the links of a given kinematic chain are classified into several link groups. The mechanisms whose ground links are in distinct link groups are determined to be non-isomorphic. Then, an improved iso...

Stiffness (or compliance) performances of three-rotation and two-translation (3R2T) overconstrained parallel mechanisms have an important influence on their applications in bio-inspired robots with precision operations. However, it is difficult to build stiffness models of the class of mechanisms due to fairly complicated structures, and an effecti...

To achieve safety, high quality, and efficiency in deep drilling, it is necessary to get formation drillability around the borehole during drilling-trajectory planning and intelligent drilling control. Since the drilling data have the characteristics of low value density and noise in the process of deep drilling, it is difficult to model formation...

Sintering process is the second most energy-consuming process in ironmarking. The main source of energy consumption is the consumption of carbon. It is significant to predict the carbon efficiency to reduce the energy consumption. In the paper, first, the comprehensive coke ratio (CCR) is defined and used as an index to measure the carbon efficienc...

The sketching of kinematic chains is important in the conceptual design of mechanisms. In general, the process of sketching kinematic chains can be divided into two steps, namely sketching topological graphs and converting them into the corresponding kinematic chains. This paper proposes a new method to automatically sketch topological graphs inclu...

The design, dynamic modelling, and workspace are presented in this paper concerning cooperative cable parallel manipulators for multiple mobile cranes (CPMMCs). The CPMMCs can handle complex tasks that are more difficult or even impossible for a single mobile crane. Kinematics and dynamics of the CPMMCs are studied on the basis of geometric methodo...

This paper presents a novel approach for the force/motion transmissibility analysis of 3 degree of freedom planar multi-loop mechanisms by drawing on the duality of twist space and wrench space. By making a comparison study on the velocity model of planar parallel mechanisms and that of planar multi-loop mechanisms, it is concluded that the velocit...

A forging manipulator principally consists of the main motion mechanism and the yawing mechanism. In this paper, the two core parts are synthesized separately to construct the configurations of forging manipulators. First, the structures and combinations of basic mechanisms are determined, based on which a computer-aided method is proposed to synth...

Based on the space curve meshing equation, in this article, a geometry design of a novel circular arc helical gear mechanism with pure rolling for parallel transmission was presented. Different from conventional circular arc gears, the meshing points of circular arc helical gears were limited at the instantaneous centre of rotation. The parameter e...

This paper presents an approach to compliance modeling of three-translation and tworotation (3T2R) overconstrained parallel manipulators, especially for those with multilink and multijoint limbs. The expressions of applied wrenches (forces/torques) exerted on joints are solved with few static equilibrium equations based on screw theory. A systemati...

A new-type of six-DOF forging manipulator which has front and rear lifting drivers is proposed. The complex vector is used to conduct a comprehensive analysis of the kinematics of the forging manipulator's major-motion mechanism. The dynamic model of the major-motion mechanism is established based on the principle of virtual work in the case of reg...

Rigidity detection is an important tool for structural synthesis of mechanisms, as it helps to unveil possible sources of inconsistency in Grübler's count of degrees of freedom (DOFs) and thus to generate consistent kinematical models of complex mechanisms. One case that has puzzled researchers over many decades is the famous "double-banana" proble...

The large face-shovel hydraulic excavator is one of the significant tools in mining, and widening its range of excavating and increasing its excavating force have been an important research trend. To realize that, this paper proposes a new type face-shovel hydraulic excavator which uses stick rockers and boom linkages to effectively increase the th...

Structural synthesis is one of the most important tasks in the creative design of mechanisms. In the past decades, spatial parallel mechanisms have been extensively synthesized. However, structural synthesis of more complex spatial mechanisms with coupling chains is seldom addressed. This paper aims to propose a general method for synthesizing a cl...

It is of great importance in the conceptual creative design of mechanical products and systems to synthesize all feasible topological structures of kinematic chains. This paper proposes a computer-aided method to synthesize all the non-fractionated kinematic chains up to six basic loops. First, the contracted graphs of kinematic chains are classifi...

Parallel mechanisms (PMs) with three degrees of freedom (DOFs) have been studied extensively, especially the PMs with two rotational and one translational DOFs (2R1T PMs). One major problem of the 2R1T PMs is the inherent parasitic motion. In this paper, a novel 2R1T symmetrical parallel mechanism with no parasitic motion is proposed and studied. T...

This paper addresses the dynamics and trajectory tracking control of cooperative multiple mobile cranes. Compared with a single mobile crane, cooperative cable parallel manipulators for multiple mobile cranes (CPMMC) are more complex in configuration, which have the characters of both series and parallel manipulators. Therefore, for the CPMMC, the...

The sketching of mechanisms (kinematic chains) shows designers a visual understanding of the interrelationship among links and joints in mechanical design, but sketching of mechanisms in manually in conceptual design stage is time-consuming and inefficient. In this paper, a fully-automatic method for sketching of planar simple and multiple joint ki...

Design of automatic gear boxes with better performance is a pursuit goal of the modern automobile industry. In order to develop CAD method for the creative design of automatic gear boxes, this paper proposes an automatic method for the structure synthesis of one degree of freedom (DOF) epicyclic gear trains (EGTs) with one main shaft which serve as...

In order to enrich the synthesis theory of planetary gearbox and meet the needs of multiple gearshifts this paper proposes a comprehensive method for the planetary gear transmission. Based on the topological graph atlas, the kinematic chains of 9-link and 2 degrees of freedom are synthesized. By the topological graph selection principle and gear fu...

Rigidity detection is a very important tool for structural synthesis of mechanisms and the processing of CAD-generated models, as it helps to unveil possible sources of inconsistency in Grübler’s count of degrees of freedom(DOF) and thus to generate consistent kinematical models of complex mechanisms. This paper proposes a loop-based rigidity detec...

This paper presents a systematic method for dealing with mobility analysis and structural synthesis of a class of important spatial mechanisms with coupling chains, which involve more complex coupling relations than spatial parallel mechanisms. First, an approach to the establishment of the motion screw equation of the class of mechanisms is derive...

Structural synthesis is one of the most important steps in the conceptual design of mechanisms and robots. The existing synthesis methods for spatial mechanisms are mainly performed by manual enumeration, which is hard to realize the automation and computerization of the conceptual design of mechanisms and robots. This paper proposes a computer-aid...

The gripper lifting track of a forging manipulator should keep as close to a straight line as possible, especially for the manufacturing of long or high-precision forged pieces. However, the lifting tracks of most forging manipulators are arc, such as DANGO & DIENENTHAL in Siegen (DDS) and Schloemann-SiemagAG Meer (SMS Meer). This paper proposes a...

A continuous finite-time control scheme for networked bilateral teleoperation is proposed in this brief. The terminal sliding mode technology is used and new master–slave torques are designed. With the new controller, the coordination error of the master manipulator and the slave manipulator converges to zero in finite time. Moreover, the reaching...

This paper deals with the error modeling and sensitivity analysis of a hybrid-driven based cable parallel manipulator (HDCPM). The HDCPM has the advantages of both cable parallel manipulator and hybrid-driven planar five-bar mechanism. Kinematics analysis and error modeling are performed based on closed loop vector conditions and direct differentia...

Conception of the kinematic structures with better performance has been a challenging, yet pivotal issue, since the beginning of the design of mechanisms or robots. This paper proposes a systematic method to synthesize and classify automatically all the valid kinematic structures of planar 3-DOF closed loop mechanisms or robots. First, after the st...

It is of great importance in the conceptual creative design of mechanical systems to synthesize as many feasible kinematic structures of mechanisms as possible. However, the methods for the structural synthesis of multiple joint kinematic chains are seldom addressed in literature even though they are widely used in various mechanical products. This...

The general motion of a spatial mechanism is a screw motion about an instantaneous screw axis (ISA). The locus of a series of ISAs will form a ruled surface, which can be called as an axode. For a spatial mechanism with only one degree of freedom (DOF), the ISAs or the axodes of the moving platform are unique. However, the axodes of the parallel me...

It is very important to synthesize as many feasible kinematic structures of mechanisms as possible in the conceptual design of mechanisms. Besides simple joint mechanisms, multiple joint mechanisms are also widely used in various mechanical systems. This paper proposes an automatic method for the synthesis of planar multiple joint kinematic chains...

This paper deals with a methodology of simultaneous optimal design of mechanism and control for completely restrained hybrid-driven based cable parallel manipulators (HDCPM) in order to improve the dynamic performance of the HDCPM system. The HDCPM have the advantages of both the cable parallel manipulator and the hybrid-driven planar five-bar mech...

In this chapter we will introduce the mobility analysis by using our mobility principle based on reciprocal screw theory. First, we discuss some simple mechanisms, and then focus on the mobility-open-issue mechanisms including the classical mechanisms and modern parallel mechanisms with interesting characteristics. Besides, more complex mechanisms,...

This chapter introduces our research on some dynamics problems of parallel mechanisms. The first problem is about the over-determinate inputs. This is quite an interesting issue. In practice, there are many machines and animals that work with over-determinate input, i.e., their input-number is much bigger than their mobility number. How to set the...