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Task-space Whole-body Control with Variable Contact Force Control for Position-controlled Humanoid Adaptation to Unknown Disturbance

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Journal of Bionic Engineering 2023年第5期20卷 2069-2087页

作者： Zelin huang Chencheng Dong Zhangguo Yu Xuechao Chen Fei Meng Qiang Huang School of Mechatronical Engineering Beijing Institute of TechnologyBeijing100081China Key Laboratory of Biomimetic Robots and Systems Ministry of EducationBeijing100081China

Whole-body control is beneficial for improving the disturbance adaptation of humanoid robots,since it can simultaneously optimize desired joint torque,joint acceleration,and contact force while considering whole-body dynamics and other physical limits.However,the lack of torque feedback information prevents the position-controlled humanoids from utilizing whole-body control directly,because it enhances the difficulty of guaranteeing desired contact force which is important for maintaining stability.In this paper,a whole-body control that integrates task-space inverse dynamics and variable contact force control is proposed for position-controlled humanoids to enhance the robot’s adaptability toward the unknown disturbance.The task-space inverse dynamics generates the desired joint acceleration and contact force with the consideration of whole-body dynamics and other limits to track the references.The variable contact force control modifies references related to Center of Mass(CoM)and end effectors to ensure reasonable contact force tracking performance,thereby assuring good tracking performance of CoM and momentum to maintain robot stability.Simulations and experiments of balancing and walking under unknown disturbance have been successfully conducted on a position-controlled humanoid robot,BHR-7P3,with the proposed method.

关键词： Whole-body control Contact force Admittance control Humanoid robot

Vibration characteristics and machining performance of a novel perforated ultrasonic vibration platform in the grinding of particulate-reinforced titanium matrix composites

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Frontiers of Mechanical Engineering 2023年第1期18卷 179-195页

作者： Yang CAO Biao ZHAO Wenfeng DING Qiang Huang National Key Laboratory of Science and Technology on Helicopter Transmission Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Ultrasonic vibration-assisted grinding(UVAG)is an advanced hybrid process for the precision machining of difficult-to-cut materials.The resonator is a critical part of the UVAG system.Its performance considerably influences the vibration amplitude and resonant frequency.In this work,a novel perforated ultrasonic vibration platform resonator was developed for UVAG.The holes were evenly arranged at the top and side surfaces of the vibration platform to improve the vibration characteristics.A modified apparent elasticity method(AEM)was proposed to reveal the influence of holes on the vibration mode.The performance of the vibration platform was evaluated by the vibration tests and UVAG experiments of particulate-reinforced titanium matrix composites.Results indicate that the reasonable distribution of holes helps improve the resonant frequency and vibration mode.The modified AEM,the finite element method,and the vibration tests show a high degree of consistency for developing the perforated ultrasonic vibration platform with a maximum frequency error of 3%.The employment of ultrasonic vibration reduces the grinding force by 36%at most,thereby decreasing the machined surface defects,such as voids,cracks,and burnout.

关键词： ultrasonic vibration-assisted grinding perforated ultrasonic vibration platform vibration characteristics apparent elasticity method grinding force surface integrity

High Dynamic Bounding and Jumping Motion of Quadruped Robot Based on Stable Optimization Control

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Journal of Bionic Engineering 2024年第1期21卷 101-111页

作者： Sai Gu Fei Meng Botao Liu Junyao Gao Qiang Huang School of Mechatronical Engineering Beijing Institute of Technology100081 BeijingChina Key Laboratory of Biomimetic Robots and Systems Ministry of EducationBeijing 100081China

Aiming at the environment such as ravines and obstacles that may be encountered in the actual movement,this paper proposes a method for optimizing the bounding and jumping motion based on the ground touching force trajectory and the air motion trajectory of the quadruped robot.The method of optimizing the ground reaction force according to the speed of the demand and the height of the jump,and adjusting the stance and swing time according to the relationship of dynamics and momentum conservation.At the same time,under the constraints of dynamics and energy consumption of the robot system,considering the jumping distance and height,a method for optimizing the air trajectory of bounding and jumping is proposed.State switching and landing stability control are also added.Finally,the experimental results show that the quadruped robot has strong bounding and jumping ability,and has achieved stable bounding movement and forward jump movement of 0.8 m.

关键词： Quadruped robot High dynamic motion control-Periodic limit cycle Trajectory optimization

High dose of tranexamic acid infusion in primary total knee arthroplasty:A randomized multicenter clinical trail

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Chinese Medical Journal 2024年第3期137卷 359-361页

作者： Jinwei Xie Qiang Huang Zeyu huang Fei Wang Jun Liu Hua Tian Wei huang Fuxing Pei Department of Orthopaedic Surgery West China HospitalSichuan UniversityChengduSichuan 610041China Department of Orthopaedic Surgery The Third Hospital of Hebei Medical UniversityShijiazhuangHebei 050051China Department of Orthopaedic Surgery Tianjin HospitalTianjin 300211China Department of Orthopaedic Surgery Peking University Third HospitalHaidian DistrictBeijing 100191China Department of Orthopaedic Surgery The First Affiliated Hospital of Chongqing Medical UniversityYuzhong DistrictChongqing 400016China

To the Editor:Significant hyperfibrinolysis is always accompanied by surgical trauma and tourniquet use in total knee arthroplasty(TKA),leading to considerable hidden blood loss,inflammation,and pain,thereby impeding the recovery process.Enhanced recovery after surgery(ERAS)has promoted the development of patient blood management in recent decades.And numerous methods of blood conservation,including tranexamic acid(TXA),a lysine analog competitive inhibitor of plasmin and plasminogen,have been studied.^([1–3])However,some issues remain controversial,such as the optimal TXA regimen in TKA.On the other hand,the use of TXA in arthroplasty is considered off-label,although the current guideline or consensus suggests its routine use in arthroplasty.

关键词： arthroplasty infusion routine

Boundedness of iterated spherical average

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Frontiers of Mathematics in China 2023年第2期18卷 125-137页

作者： Rui BU Qiang Huang Yingjun SHAO Department of Mathematics Qingdao University of Science and TechnologyQingdao 266000China Department of Mathematical Sciences Zhejiang Normal UniversityJinhua 321000China

The iterated spherical average∆(A1)^(N)is an important operator in harmonic analysis,and has very important applications in approximation theory and probability theory,where∆is the Laplacian,A_(1)is the unit spherical average and(A1)^(N)is its iteration.In this paper,we mainly study the sufficient and necessary conditions for the boundedness of this operator in Besov-Lipschitz space,and prove the boundedness of the operator in Triebel-Lizorkin space.Moreover,we use above conclusions to improve the existing results of the boundedness of this operator in L^(p)space.

关键词： Iterated spherical average Besov-Lipschitz space Triebel-Lizorkin space L^(p)space

Experimental and numerical study of coal mechanical properties during coalification jumps

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Frontiers of Earth Science 2023年第1期17卷 45-57页

作者： Qiang Huang Xuehai FU Jian SHEN qiangling YAO Ming CHENG Key Laboratory of Coalbed Methane Resources&Reservoir Formation Process(Ministry of Education) China University of Mining and TechnologyXuzhou 221116China School of Mines Key Laboratory of Deep Coal Resource MiningMinistry of EducationChina University of Mining&TechnologyXuzhou 221116China

The mechanical characteristics of coal reservoirs are important parameters in the hydraulic fracturing of coal.In this study,coal samples of different ranks were collected from 12 coal mines located in Xinjiang and Shanxi,China.The coal ranks were identified with by the increased Maximum vitrine reflectance(Ro,max)value.The triaxial compression experiments were performed to determine the confining pressure effect on the mechanical properties of coal samples of different ranks.The numerical approaches,including the power function,arctangent,and exponential function models,were used to find the correlation between coal elastic modulus and the confining pressure.The fitting equations of compressive strength and elastic modulus of coal ranks were constructed under different confining pressures.The results showed that the coal compressive strength of different ranks has a positive linear correlation with the confining pressure.The coal elastic modulus and confining pressure showed an exponential function.Poisson’s ratio of coal and confining pressure show negative logarithmic function.The stress sensitivity of the coal elastic modulus decreases with the increase of confining pressure.The coalification jump identifies that the compressive strength,elastic modulus,and stress sensitivity coefficient of coal have a polynomial relationship with the increase of coal ranks.The inflection points in coalification at Ro,max=0.70%,1.30%,and 2.40%,are the first,second,and third coalification jumps.These findings provide significant support to coal fracturing during CBM production.

关键词： compressive strength elastic modulus confining pressure Poisson’s ratio coalification jump

Enantioselective total syntheses of marine natural products(+)-cylindricines C,D,E and their diastereomers

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Organic Chemistry Frontiers 2022年第1期9卷 58-63页

作者： Ying-Hong huang Zhan-Jiang Liu Pei-Qiang Huang Department of Chemistry Fujian Provincial Key Laboratory of Chemical BiologyCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamenFujian 361005P.R.China

A seven-step total synthesis of(+)-cylindricine D and epi-cylindricine D is described.The efficiency relies on the highly diastereoselective reductive bis-functionalization of N,O-protected(S)-pyroglutaminol by our recently improved protocol to build the N-α-tert-alkylamine motif,and a telescoped one-step fourreaction protocol to build the fused bicyclic ring system.(+)-Cylindricine C and its 2-epimer were synthesized by essentially the same sequence in eight steps.Acetylation of the latter then delivered(+)-cylindricine E and its 2-epimer,respectively.

关键词： latter steps essentially

Circular RNA hsacirc0000745 may serve as a diagnostic marker for gastric cancer

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World Journal of Gastroenterology 2017年第34期23卷 6330-6338页

作者： Mei huang Yi-Ren He Li-Chuan Liang Qiang Huang Zhi-qiang Zhu Anhui Province Key Laboratory of Hepatopancreatobiliary Surgery Department of General SurgeryAnhui Provincial Hospital Affiliated to Anhui Medical University Department of General Surgery Anhui Provincial Hospital Affiliated to Anhui Medical University

AIM To determine whether circular RNAs(circ RNAs) are involved in pathological processes of gastric cancer(GC).METHODS Three circ RNAs with differential expression in GC and colorectal cancer were randomly selected for validation by quantitative reverse transcription-polymerase chain reaction(q RT-PCR), using 20 pairs of gastric tissues and normal tissues. Based on the predicted circ RNAmi RNA network, we then focused on hsa_circ_0000745, which was found to be down-regulated in 20 GC tissues compared with normal tissues. The hsa_circ_0000745 levels were further analyzed by q RT-PCR in 60 GC tissues and paired adjacent non-tumor tissues, as well as 60 plasma samples from GC patients and 60 plasma samples from healthy controls. The associations between the levels of hsa_circ_0000745 and the clinicopathological features of GC patients were statistically assessed. A receiver operating characteristic(ROC) curve was used to evaluate the diagnostic value of hsa_circ_0000745 in GC.RESULTS Hsa_circ_0000745 was down-regulated in GC tissues vs non-tumorous tissues(P < 0.001) and in plasma samples from patients with GC vs healthy controls(P < 0.001). The expression level of hsa_circ_0000745 in GC tissues correlated with tumor differentiation, while the expression level in plasma correlated with tumor-nodemetastasis stage. The area under the ROC curve(AUC) of hsa_circ_0000745 in plasma was 0.683, suggesting good diagnostic value. Plasma hsa_circ_0000745 level combined with carcinoembryogenic antigen(CEA) level increased the AUC to 0.775.CONCLUSION Hsa_circ_0000745 plays an important role in GC and its expression level in plasma in combination with CEA level is a promising diagnostic marker for this malignancy.

关键词：圆形的 RNA circ_0000745 胃的癌症诊断 Noncoding RNA

Low Complexity Joint Spectrum Resource and Power Allocation for Ultra Dense Networks

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China Communications 2023年第5期20卷 104-118页

作者： qiang Wang Yanhu huang Qingxiu Ma Guangxi Colleges and Universities Key Laboratory of Complex System Optimization and Big Data Processing Yulin Normal UniversityYulin 537000China

In this paper,we propose a low complexity spectrum resource allocation scheme cross the access points(APs)for the ultra dense networks(UDNs),in which all the APs are divided into several AP groups(APGs)and the total bandwidth is divided into several narrow band spectrum resources and each spectrum resource is allocated to APGs independently to decrease the interference among the cells.Furthermore,we investigate the joint spectrum and power allocation problem in UDNs to maximize the overall throughput.The problem is formulated as a mixed-integer nonconvex optimization(MINCP)problem which is difficult to solve in general.The joint optimization problem is decomposed into two subproblems in terms of the spectrum allocation and power allocation respectively.For the spectrum allocation,we model it as a auction problem and a combinatorial auction approach is proposed to tackle it.In addition,the DC programming method is adopted to optimize the power allocation subproblem.To decrease the signaling and computational overhead,we propose a distributed algorithm based on the Lagrangian dual method.Simulation results illustrate that the proposed algorithm can effectively improve the system throughput.

关键词： ultra dense networks resource allocation combinatorial auction optimization algorithm