For the purpose of exploring deformation characteristics of jointed rock masses, influence of joint inclination and confining pressure on the mechanical behavior of discontinuous rock a series of compression tests were conducted under satisfactory testing conditions on three types of sandstone from various locations. Three groups of jointed specimens were used in this research, including specim...

A new simulation model was created with a transfemoral prosthesis including a residual limb muscle model during the swing phase. The optimal knee joint friction value was calculated to minimize muscle metabolic energy expenditure. Using this model to examine how an amputee could walk as fast as possible, the minimum swing duration was calculated. The obtained optimal joint friction value was cl...

Open Dynamics Engine (ODE) is the most popular rigidbody dynamics implementation for robotics simulation applications. While using it to simulate common robotic scenarios like mobile robot locomotion and simple grasping, we have identified the following shortcomings each of which adversely affect robot simulation: lack of computational efficiency, poor support for practical joint-dampening, ina...

this paper proposes a gait planning approach to reduce the required friction for a biped robot walking on various surfaces. to this end, a humanoid robot with 18 dof is considered to develop a dynamics model for studying various 3d manoeuvres. then, feasible trajectories are developed to alleviate the fluctuations on the upper body to resemble human-like walking. in order to generate feasible w...

accurate delivery of torque to implant screws is critical to generate ideal preload in the screw joint and to offer protection against screw loosening. mechanical torque-limiting devices (mtlds) are available for this reason. in this study, the accuracy of one type of friction-style and two types of spring-style mtlds at baseline, following fatigue conditions and sterilization processes were de...

The existing connection between the concrete-filled double steel tubular (CFDST) column and reinforced concrete (RC) beam is difficult to repair reuse after damage. In this paper, a self-centering joint CFDST RC proposed. of realized by prestressed strands, energy dissipation friction. overall purpose research analyze influence strand friction on mechanical behavior joint. By comparing envelope...

Coulomb friction is inevitable in every mechanical system with contact motion. When the mechanical system with Coulomb friction is under feedback control, it can destabilize the system by generating limit cycles. Controlled mechanical systems with ideal Coulomb friction can be viewed as a particular class of relay feedback systems characterized by the zero DC gain property and the positivity of...

The purpose of the study was to investigate how novice runners adjust their lower extremities in heel-toe running while they wear dress shoes and running shoes. Ten novice male runners repeatedly ran across a force plate at 4 m/s in each type of shoes. Joint kinematics and kinetics, vertical ground reaction force, and utilized coefficient of friction during the stance phase were quantified. The...

This paper presents a control strategy for a two-link manipulator with revolute joints (2R) with an unactuated second joint, wherein the motion of the system is confined to a horizontal plane. The model takes into account the frictional forces present in the system. The control objective is to move the end-effector from a given position to a target point. The methodology involves two stages. In...

This paper describes two approaches for the simultaneous identification of the coulomb and viscous parameters in kinematical joints. One is a time-domain method (TDM) and the other is a frequency-domain method (FDM). Simulation shows that both of the two methods have good performances in identifying friction at high SNR (90dB). But at low SNR (20dB), the estimation accuracy of the frequency-dom...