ESTIMATE ACCURACY OF NONLINEAR COEFFICIENTS OF SQUEEZEFILM DAMPER USING STATE VARIABLE FILTER METHOD

ＥＳＴＩＭＡＴＥＡＣＣＵＲＡＣＹＯＦＮＯＮＬＩＮＥＡＲＣＯＥＦＦＩＣＩＥＮＴＳＯＦＳＱＵＥＥＺＥＦＩＬＭＤＡＭＰＥＲＵＳＩＮＧＳＴＡＴＥＶＡＲＩＡＢＬＥＦＩＬＴＥＲＭＥＴＨＯＤＺｈａｎｇＹｏｕｙｕｎＴｈｅｏｒｙｏｆＬｕｂｒｉｃａｔｉｏｎａｎｄＢｅａｒ...     

机器人力控制系统稳定性分析及振动抑制

利用Ｌａｇｒａｎｇｅ动力学方程对普通机器人和ＭＡＣＲＯ／ＭＩＣＲＯ组合式机器人两种力控制系统的稳定性进行了分析，分析表明后者更稳定。由于ＭＡＣＲＯ机器人结构动态和力传感器动态的影响，组合式机器人在高频时存在着共振与反共振，为了提高系统的高频性能，提出了一种优化粘性阻尼系数的方法，结果表明，当驱动力为０．５Ｎ时，采用此方法可以使机器人与环境的接触力的变化范围由０．１９～１．１２Ｎ减小为０．４４～０．５０Ｎ。     

NEW AUTOREGRESSIVE MOVING AVERAGE SPECTRUM ESTIMATION AND CEPSTRUM ALGORITHM

ＮＥＷＡＵＴＯＲＥＧＲＥＳＳＩＶＥＭＯＶＩＮＧＡＶＥＲＡＧＥＳＰＥＣＴＲＵＭＥＳＴＩＭＡＴＩＯＮＡＮＤＣＥＰＳＴＲＵＭＡＬＧＯＲＩＴＨＭＺｈｏｕＺｈａｏｊｉｎｇ，ＣｈｅｎｇＪｉｅＣｈｉｎａＩｎｓｔｉｔｕｔｅｏｆＭｅｔｒｏｌｏｇｙＡｂｓｔｒａｃｔＢａｓ...     

INVESTIGATION INTO THE DEGRADATION OF CUTTING FLUIDS IN A WORKSHOP ENVIRONMENT

ＩＮＶＥＳＴＩＧＡＴＩＯＮＩＮＴＯＴＨＥＤＥＧＲＡＤＡＴＩＯＮＯＦＣＵＴＴＩＮＧＦＬＵＩＤＳＩＮＡＷＯＲＫＳＨＯＰＥＮＶＩＲＯＮＭＥＮＴＳｕｌｉｍａｎＳＭＡ，ＮａｂｈａｎＭＢ，ＵｎｉｖｅｒｓｉｔｙｏｆＢａｈｒａｉｎ，ＡｂｕｂａｋｒＭＩ，ＡｍｅｒｉＣｏ...     

ANALOG SIMULATION OF DYNAMIC RESPONSE IN DRY FRICTION PAIR BY THERMODYNAMICS

ＡＮＡＬＯＧＳＩＭＵＬＡＴＩＯＮＯＦＤＹＮＡＭＩＣＲＥＳＰＯＮＳＥＩＮＤＲＹＦＲＩＣＴＩＯＮＰＡＩＲＢＹＴＨＥＲＭＯＤＹＮＡＭＩＣＳ￥ＪｉｎＣｈａｎｇｓｈａｎ；ＥＫａｎｎａｔｅｙ－Ａｓｉｂｕ，Ｊｒ（ＨａｒｂｉｎｉｎｓｔｉｔｕｔｅｏｆＴｅｃｈｎｏｌｏｇ...     

REACTION MECHANISM AND DYNAMICS OF PASTE BORONIZING IN A PLASMA

ＲＥＡＣＴＩＯＮＭＥＣＨＡＮＩＳＭＡＮＤＤＹＮＡＭＩＣＳＯＦＰＡＳＴＥＢＯＲＯＮＩＺＩＮＧＩＮＡＰＬＡＳＭＡＬｉＣｈｕｎｙａｎｇ，ＨａｎＬｉｍｉｎ，ＷａｎｇＪｉａｎ，ＬｉｕＲｕｉｘｉａｎ，ＴｉａｎｊｉｎＵｎｉｖｅｒｓｉｔｙＡｂｓｔｒａｃｔＴｈｅｄｉｓ...     

PROJECTION OF ARBITRARY POINT TO PARAME-TRIC BEZIER SURFACE AND ITS APPLICATION IN COMPLEX SURFACE N

ＰＲＯＪＥＣＴＩＯＮＯＦＡＲＢＩＴＲＡＲＹＰＯＩＮＴＴＯＰＡＲＡＭＥ－ＴＲＩＣＢＥＺＩＥＲＳＵＲＦＡＣＥＡＮＤＩＴＳＡＰＰＬＩＣＡＴＩＯＮＩＮＣＯＭＰＬＥＸＳＵＲＦＡＣＥＮＣＭＥＡＳＵＲＩＮＧＡＮＡＬＹＳＩＳＬｉＪｉａｎｇｘｉｏｎｇ，ＫｅＹｉｎｇｌｉ...     

DIRECT INTERPOLATION AND ADAPTIVE MACHINING OF COMPOUND SURFACES

ＤＩＲＥＣＴＩＮＴＥＲＰＯＬＡＴＩＯＮＡＮＤＡＤＡＰＴＩＶＥＭＡＣＨＩＮＩＮＧＯＦＣＯＭＰＯＵＮＤＳＵＲＦＡＣＥＳＺｈｏｕＹｕｎｆｅｉ，ＧａｏＳａｎｄｅ，ＺｈｏｕＪｉＨｕａｚｈｏｎｇＵｎｉｖｅｒｓｉｔｙｏｆＳｃｉｅｎｃｅａｎｄＴｅｃｈｎｏｌｏｇｙＡｂ...     

FTIR定量分析润滑油中的ZDDP

根据Ｐ－Ｅ公司ＦＴＩＲ定量软件原理，设计分析方法进行润滑油中ＺＤＤＰ含量的测定，数据误差小于５％，与ＭＯＡ油料光谱仪再现性小于１５％。本方法对于润滑油中ＺＤＤＰ的定量分析有很大实际应用价值。     

结构陶瓷磨削力的实验研究

通过对３种典型结构陶瓷材料９Ｍｇ－ＰＳＺ，Ｓｉ３Ｎ４及Ａｌ２Ｏ３的磨削力实验，就结构陶瓷的磨削力、磨削力比，磨削比能及磨削力的频率特征进行研究，表明结构陶瓷的磨削力有独特的规律。     

Fabrication of four-point biped robot foot module based on contact-resistance force sensor and its evaluation

This paper presents the design of robot foot module of four-point biped walking robot and its fabrication. The foot module has four sensor units based on contact-resistance force sensor. The thin-film-type force sensor is fabricated by coating resistive ink on thin polyimide film using silk screening technique. The simple structure is devised and fabricated to assemble the thin force sensor rigidly. The unit force sensor module is evaluated by the calibration setup to obtain the characteristics of repeatability and hysteresis. The sensor module presents hysteresis error of about 5% and repeatability error of about 0.37%. The calculated zero moment point (ZMP) of the foot module is also compared with the measured position using static load of 50 N. The maximum location error of ZMP is less than 10%. The robot foot module shows the possibility of applying it to humanoid walking.     

A hybrid controller based on CPG and ZMP for biped locomotion

Biped locomotion has attracted much attention in recent years. The most successful implemented methods in this area are based on two approaches, central pattern generator (CPG) and zero moment point (ZMP). Unfortunately, neither of these concepts can solely solve the movement challenge completely. In this study, we introduce a hybrid controller to combine the advantages of these methods. The proposed controller is based on two major approaches, CPG and ZMP. This hybrid controller is composed of a trajectory control system and a trajectory generator system. The trajectory control system applied to keep the robot stable uses ZMP as a real time control feedback. The trajectory generator system, which is composed of nonlinear oscillators, generates stable motions. The parameters of CPG are tuned by a new two-stage approach using differential evolution (DE) and bees algorithm (BA). Furthermore, performance of the proposed controller is verified using the robotic simulation software Webots.     

BP神经网络在拟人机器人步态稳定性中的应用

步态稳定是拟人机器人行走研究中的重要课题。介绍了零力矩点与稳定行走的关系,并假设机器人脚底装有力传感器。采用BP神经网络建立拟人机器人步态稳定的模型,仿真结果表明该方法简单易行,能够提高机器人步态稳定的实时性。     

Receding horizon viability radius for stability of humanoid robot under external perturbation

In this paper, a new approach that uses the rate of change of the angular momentum about the center of mass (COM) to improve the balance of a humanoid robot is proposed. This approach is motivated by how humans balance themselves when standing, walking, and running by making use of their upper body and swinging legs. Human movements such as lunging forward or backward and rotating arms make use of angular momentum to maintain balance. As the external perturbation increases, a human instinctively decides when and where to take a step to avoid a fall. In the same manner, a humanoid robot subjected to an external perturbation can determine whether to remain standing or to take a step with a swinging leg to maintain balance using RHVR conditions obtained from the proposed linear inverted dumbbell model. The rotation of a dumbbell model with mass inertia is an easy expression of the angular momentum of an upper body, arms, and legs. A zero-moment point (ZMP) outside the support polygon indicates an unbalanced gait and cannot represent a physical point related to the sole of the robot foot, which is defined as pseudo-ZMP (PZMP) in this paper. PZMP located outside the support area provides useful information for balancing the gait. PZMP from the foot edge provides a measure of the unbalanced moment that tends to rotate the humanoid robot around the supporting foot and causes it to fall. It is shown that PZMP is determined by the Gauss’s principle within mechanical constraints of the rate of change of angular momentum about COM. In fact, the actual angular acceleration about COM is determined by the Gauss’s principle. Additionally, RHVRs is defined, that is, viability regions to keep the balance that indicate the essential range of stability implemented to a real system. RHVRs are divided into the real ZMP (RZMP), PZMP and stepping PZMP (SPZMP). Hence, the regions of RHVR and the actual angular acceleration about COM determine which of the three control strategies is used.     

基于自适应结构的仿袋鼠机器人脚部研究及设计

根据袋鼠的生物结构特征,建立了仿袋鼠跳跃机器人的刚柔混合模型。利用自适应结构的可控性,将其应用于仿生跳跃机器人领域,来实现跳跃机器人在不同跳跃速度下的脚部轮廓变形以及在跳跃过程中脚部的变形。在SolidWorks中建立自适应结构脚的三维模型,运用拉格朗日方法建立机器人动力学方程,在此基础上,用ZMP法建立其落地稳定性的求解方程。结合实例仿真结果表明:具有自适应结构的变形脚有助于提高机器人在着地过程中的落地稳定性,增大起跳时间和调整起跳角度。     

四足轮腿式移动机器人的步态分析及轨迹规划

针对外星复杂的地表环境,基于2-UPS/(S+SPR)R闭环并联机构,设计了一种四足轮腿式移动机器人。通过对比机器人在运动过程中的稳定裕度与重心调整量得到最优步态,利用ZMP法衡量了机器人在静步态下的稳定性,并用改进的复合摆线法规划了足端的运动轨迹。在整个运动过程中,机械腿运动平稳,速度、加速度变化较为平滑,不会出现对机械腿造成损坏的较强冲击;且在抬腿和着地瞬间,速度、加速度均为0,不会对机身产生冲击。分析结果表明,该四足轮腿式移动机器人运动灵活且平稳,适用于外太空的探测。     

两足机器人步行运动参数对单足支撑期ZMP点影响的研究

在两足步行机器人的研究中,一般将零力矩点(ZMP点)的位置与支撑范围的关系作为判别其步行稳定性的依据.提出一种通用的方法,来分析两足机器人的步行运动参数对ZMP点位置的影响,并通过对机器人单足支撑期运动的计算机仿真,试图得到步行运动参数的变化对稳定性影响的规律,以期对机器人动态步行的稳定性设计提供实用的参考.     

Simulation of exoskeleton sit-to-stand movement

Problems of simulating the processes of exoskeleton sit-to-stand movement are considered. A mathematical model of the device is described. The diagram of an automatic control system is proposed, based on the ZMP method. The results of the mathematical simulating are given. It is shown that the proposed control system makes verticalization possible without falling from a wide range of initial conditions.     

基于遗传算法优化的仿人足球机器人步态规划研究

针对机器人足球比赛的特点及实现仿人足球机器人稳定快速步行的要求,提出了一种基于遗传算法优化的步态规划方法。首先,分析了仿人足球机器人一个完整步行周期的运动过程,根据步行中髋关节运动连续和踝关节运动间断的特点,分别采用三次样条插值与高次多项式插值进行了轨迹插值;其次,以零力矩点（ZMP）稳定裕度为参数构造了目标函数;最后,利用遗传算法（GA）对规划的步态进行了优化,从而得到了ZMP稳定裕度相对较大的稳定步态。仿真结果表明,该方法规划的步态能实现仿人足球机器人更稳定地步行。     

基于ZMP法的仿袋鼠跳跃机器人着地阶段运动稳定性分析

基于仿袋鼠跳跃机器人五刚体机构模型,运用拉格朗日法,建立了跳跃机器人系统着地阶段的动力学方程,采用ZMP法研究了仿袋鼠弹跳机器人的运动稳定性,提出了其着地运动稳定裕度的计算方法和判据;采用Matlab仿真工具,结合实例分析,对机器人着地阶段各关节驱动力矩以及ZMP点的变化情况进行了仿真,并提出了改进刚性模型着地运动稳定性的方法。仿真结果表明:ZMP法在此模型上分析是有效的。