CONTRIBUTION TO THE INTEGRATED CONTROL OF BIPED LOCOMOTION MECHANISMS

2007 ◽  
Vol 04 (01) ◽  
pp. 49-96 ◽  
Author(s):  
MIOMIR K. VUKOBRATOVIĆ ◽  
ALEKSANDAR D. RODIĆ

This work is concerned with the integrated dynamic control of humanoid locomotion mechanisms based on the spatial dynamic model of the humanoid mechanism, a servo system model, and an environment model. The control scheme was synthesized using the centralized model of the system and the hierarchical principle, with tactical and executive control levels. The proposed structure of the dynamic controller involves four feedback loops: position-velocity feedback at the robotic mechanism joints, dynamic reaction feedback at Zero-Moment Point, impact force feedback at the instant when the foot strikes the ground, and the load feedback of the mechanism joints. Simulation experiments are carried out for a number of characteristic examples. The numerical results obtained, along with theoretical study, serve as the basis for a critical evaluation of the performance of the devised controller.

Vestnik MGSU ◽  
2021 ◽  
pp. 486-492
Author(s):  
Oleg D. Samarin

Introduction. It is noted that the improvement of the technology for calculating the thermal regime of premises in the conditions of automation of climate systems is still relevant. The aim of the work is to find a universal dependence of the air temperature in the building premises on time in conditions of a jump in heat access or heat loss for the integral law of regulating the compensatory heat flow from microclimate systems. In the form of a scientific hypothesis, we consider the statement about the power nature of such a dependence with the presence of a maximum and an asymptotic tendency to zero. Materials and methods. The study involves the use of basic equations that relate the most significant components of heat flows in rooms serviced by microclimate systems equipped with integrated controllers under conditions of abrupt changes in thermal disturbances. The method of dimension analysis is used to identify dimensionless complexes that are essential for obtaining engineering dependencies, as well as software calculation of sums of infinite series with a given accuracy, numerical solution of nonlinear equations, and the method of power series economization. Results. An analytical expression is found for changes in room temperature under integrated control of climate equipment under conditions of a jump in heat availability, which has the form of an infinite series in degrees of a dimensionless parameter that characterizes the properties of the room and the automation system. A simplified expression for the deviation of air temperature is obtained and a formula for the required control time is derived, as well as its estimation is given on the example of one residential building in the climatic conditions of Moscow. Conclusions. It is shown that the dependence of the air temperature in a room serviced by microclimate systems with integrated controllers on time is represented in a universal dimensionless form, suitable for any objects regardless of their specific characteristics. The previously discovered relationships for the moment of maximum deviation and the value of the dynamic control error depending on the air exchange of the room, the transmission coefficient of the controller and the room’s own heat stability are confirmed and refined.


2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Xun Li ◽  
Yu-Feng Zang ◽  
Han Zhang

We applied a “temporal decomposition” method, which decomposed a single brain functional network into several “modes”; each of them dominated a short temporal period, on a continuous, “state-” related, “finger-force feedback” functional magnetic resonance imaging experiment. With the hypothesis that attention and internal/external information processing interaction could be manipulated by different (real and sham) feedback conditions, we investigated functional network dynamics of the “default mode,” “executive control,” and sensorimotor networks. They were decomposed into several modes. During real feedback, the occurrence of “default mode-executive control competition-related” mode was higher than that during sham feedback (P=0.0003); the “default mode-visual facilitation-related” mode more frequently appeared during sham than real feedback (P=0.0004). However, the dynamics of the sensorimotor network did not change significantly between two conditions (P>0.05). Our results indicated that the visual-guided motor feedback involves higher cognitive functional networks rather than primary motor network. The dynamics monitoring of inner and outside environment and multisensory integration could be the mechanisms. This study is an extension of our previous region-specific and static-styled study of our brain functional architecture.


Author(s):  
Bennett Breese ◽  
Drew Scott ◽  
Shraddha Barawkar ◽  
Manish Kumar

Abstract Tethered drone systems can be used to perform long-endurance tasks such as area surveillance and relay stations for wireless communication. However, all the existing systems use tethers only for data and power transmission from a stationary point on the ground. This work presents a control strategy that enables a quadcopter to follow a moving tether anchor. A force feedback controller is implemented using Fuzzy Logic. Using force-based strategy provides effective compliance between the tether’s anchor and the drone. The drone can thus be controlled by mere physical movement/manipulation of tether. This enhances the safety of current tethered drone systems and simplifies the flying of drones. Fuzzy Logic provides an intuitive edge to the control of such systems and allows handling noise in force sensors. Extensive simulation results are presented in this paper showing the effectiveness of the proposed control scheme.


2020 ◽  
pp. 107754632097290
Author(s):  
You-cheng Zeng ◽  
Hu Ding ◽  
Rong-Hua Du ◽  
Li-Qun Chen

In this article, a novel vibration control scheme of suspension systems is proposed. It combines the advantages of quasi-zero stiffness isolator, nonlinear energy sink absorber, and inerter. This proposed scheme can achieve low transmissibility, low amplitude, and low additional weight and resolve the conflict between riding comfort and handling stability. Strong nonlinear vibration equations of a quarter-vehicle suspension system are established. It also presents the detailed process of high-order harmonic approximation to obtain steady-state responses. Moreover, approximate solutions are validated by a numerical method. Furthermore, based on riding comfort and handling stability, the following four suspension systems are evaluated and compared, namely, 2-degree-of-freedom quarter-vehicle model, 2-degree-of-freedom quarter-vehicle with quasi-zero stiffness isolator, 2-degree-of-freedom quarter-vehicle with inerter-nonlinear energy sink absorber, and 2-degree-of-freedom quarter-vehicle integrated control scheme with quasi-zero stiffness and inerter-nonlinear energy sink. It is found that the integrated control scheme with quasi-zero stiffness and inerter-nonlinear energy sink can significantly improve the riding comfort and handling stability at the same time. In addition, the effects of system parameters are studied carefully. The results show that based on the reasonable design of the control system parameters, better riding comfort and handling stability can be obtained. In short, this article provides a theoretical basis for integrating quasi-zero stiffness isolators and inerter-nonlinear energy sink absorbers to improve the riding comfort and handling stability.


2013 ◽  
Vol 397-400 ◽  
pp. 1214-1219
Author(s):  
Xia Bai ◽  
Da Lu Guan ◽  
Chen Rui

This paper combines hardware reliability and software mobility with modern intelligent control through the analysis of the control object using intelligent decoupling control scheme to control the pressure control system of the large gas collector in coke oven. By using expert control strategies based on the DCS, the paper develops the system design which is versatile and effective.


2020 ◽  
Vol 10 (22) ◽  
pp. 8031
Author(s):  
Long Qin ◽  
Fanghao Huang ◽  
Zheng Chen ◽  
Wei Song ◽  
Shiqiang Zhu

Hyper-redundant continuum manipulators present dexterous kinematic skills in complicated tasks and demonstrate promising potential in underground exploration, intra-cavity inspection, surgery, etc. However, the hyper-redundancy, which endows much dexterity and flexibility, brings a huge challenge to the kinematics solution and control of the continuum manipulators. Due to the pseudoinverse calculation of high-order Jacobian matrix or iteration, many inverse kinematic solution approaches of continuum manipulators are very time-consuming, which extremely limit their applicability in real-time control. Additionally, it is often difficult for the manipulators to perform the tasks well in complex scenarios due to lack of human intervention. Therefore, in this paper, a simplified kinematics model of a typical hyper-redundant manipulator is proposed based on its unique geometry relationships, where the mapping relationships between the actuators’ rotation and the end-effector’s position are derived through the analysis of its driving subsystem and motion subsystem, in particular the joint modules. To perform the tasks of manipulators with the help of operators, a teleoperation control scheme with modified wave transmission structure is designed to achieve the guaranteed stability and improved transparency, and the leader’s trajectory and generated force feedback are the transmitted signals in the communication channel. Specifically, a virtual force feedback generation algorithm is developed in the teleoperation control scheme via the processing tracking errors, which can improve the operators’ assistance and perception during the teleoperation process. The practical experiments with comparative wave variable structures in two different sets are implemented to verify the effectiveness of proposed kinematics model and control scheme.


2004 ◽  
Vol 16 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Shugen Ma ◽  
◽  
Mitsuru Watanabe ◽  

Hyper-redundant manipulators have high number of kinematic degrees of freedom, and possess unconventional features such as the ability to enter narrow spaces while avoiding obstacles. To control these hyper-redundant manipulators accurately, manipulator dynamics should be considered. This is, however, time-comsuming and makes implementation of real-time control difficult. In this paper, we propose a dynamic control scheme for hyper-redundant manipulators, which is based on analysis in defined posture space where three parameters were used to determine the manipulator posture. Manipulator dynamics are modeled on the parameterized form with the parameter of the posture space path. The posture space path-tracking feed-forward controller is then formulated on the basis of a parameterized dynamic equation. Computer simulation, in which a hyper-redundant manipulator traces the posture space path well by using the proposed feed-forward controller, proved that the hyper-redundant manipulator tracks the workspace path accurately.


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