Metal mines mined using the sublevel caving method often exhibit various environmental problems on ground surface. This can affect safety of production process in mining area. A numerical model Universal Distinct Element Code has been established to investigate deformation failure giving rise this underground mining. The calculations are combined with in-situ monitoring data collected over a pe...

For many industrial parts, their natural resting pose differs from the orientation desired for assembly. We have found that it is possible in many cases to compensate for this difference using a parallel-jaw gripper with fixed orientation. The idea is to arrange contact points on each gripper jaw so that the part is reoriented as it is grasped. We analyze the mechanics of compensatory grasping ...

The deformation failure modes of gravity retaining walls include overturning, toppling, deep sliding, and eccentric failure. complex mode, which involves the multi-stage walls, suffers from a lack mechanical models design theories. Based on basic theory reinforced concrete construction, this study established calculation model bottom-confined (RC-GRWs), are composed tensile, compressive, rigid ...

This Note presents a new asymmetric flexure design, the double parallelogram-tilted-beam double parallelogram (DP-TDP) flexure, that enables two times higher stroke in electrostatic comb-drive actuators, compared to the traditional symmetrically paired double parallelogram (DP-DP) flexure, while maintaining the same device footprint. Because of its unique kinematic configuration, the DP-TDP fle...

As a kind of important flexible joint, two-axis flexure hinges can realize in-plane and out-of-plane motions and can be used for constructing flexure-based spatial compliant mechanisms. The paper introduces a common two-axis elliptical-arc-filleted flexure hinge that is generated by two different elliptical-arc-filleted cutout profiles and that provides some new hinge types. The analytical comp...

A novel flexure hinge named half circular-elliptical hybrid flexure hinge was presented. Based on Castigliano’s Displacement Theorem, the compliance equations of the novel flexure hinge were formulated. A computer aided analysis and parametric design program of the half circular-elliptical hybrid flexure hinge was developed by VC++6.0. A specific half circular-elliptical hybrid flexure hinge wa...

The Bethe ansatz method and an iterative procedure based on detailed balance are used to obtain exact results for an asymmetric avalanche process on a ring. The average velocity of particle flow, v, is derived as a function of the toppling probabilities and the density of particles, rho. As rho increases, the system shows a transition from intermittent to continuous flow, and v diverges at a cr...