This paper presents a minimal invariant coordinate-free description of rigid body motion trajectories. Based on a motion model for the instantaneous screw axis, a time-based coordinate-free description consisting of six scalar functions of time is defined. Analytical formulas are presented to obtain these functions from the pose or twist coordinates of a motion trajectory. The time-based functi...

A three-dimensional representation of rigid body dynamic equations becomes possible by introducing the dual inertia operator. This paper generalizes this result and by using motor transformation rules and the dual inertia operator, gives a general expression for the three-dimensional dynamic equation of a rigid body with respect to an arbitrary point. Then, the dual Lagrange equation is formula...

In this paper, an algorithm for dynamic rigid-body model is considered. To this end, we first develop an equivalent reformulation of the problem via the Fischer function. Based on this, we propose a new type of method for solving the problem, and the algorithm is shown to be globally convergent and quadratically convergent without nondegenerate assumption. Keywordsdynamic rigid-body model; line...

Whether a rigid body limits maneuverability depends on how maneuverability is defined. By the current definition, the minimum radius of the turn, a rigid-bodied, spotted boxfish Ostracion meleagris approaches maximum maneuverability, i.e. it can spin around with minimum turning radii near zero. The radius of the minimum space required to turn is an alternative measure of maneuverability. By thi...

The general formulation of the mechanics of an affinely-rigid body in n dimensions was presented in [1, 2, 3]. Obviously, it is the special case n = 3 that is directly physically applicable, if a proper potential model is chosen. For realistic potentials, the three-dimensional problem is very difficult. The reason is that the group SO(3, IR) (and generally SO(n, IR) for n > 2) is semisimple and...

Rigid-body dynamics with unilateral contact is a good approximation for a wide range of everyday phenomena, from the operation of car brakes to walking to rock slides. It is also of vital importance for simulating robots, virtual reality, and realistic animation. However, correctly modeling rigid-body dynamics with friction is difficult due to a number of discontinuities in the behavior of rigi...

An algorithm is described for recovering the six degrees of freedom of motion of a vehicle from a sequence of range images of a static environment taken by a range camera rigidly attached to the vehicle. The technique utilizes a least-squares minimization of the difference between the measured rate of change of elevation at a point and the rate predicted by the so-called elevation rate constmin...

Introduction Tracheobronchial foreign body aspiration is a common life-threatening condition in children. There are controversies in the management of this condition, including the type of ventilation during bronchoscopy.  This study aims to compare anesthesia with controlled ventilation versus spontaneous ventilation in rigid bronchoscopy in children with foreign body aspiration.  Materials...

Tay [6] characterized the multigraphs which can be realized as infinitesimally rigid d-dimensional body-and-bar frameworks. Subsequently, Tay [7] and Whiteley [11] independently characterized the multigraphs which can be realized as infinitesimally rigid d-dimensional body-and-hinge frameworks. We adapt Whiteley’s proof technique to characterize the multigraphs which can be realized as infinite...

In this paper, we study the quasi-static motion of an elastically suspended, unilaterally constrained rigid body. The motion of the rigid body is determined, in part, by the position controlled motion of its support base and by the behavior of the elastic suspension that couples the part to the support. The motion is also determined, in part, by contact with a frictional surface that both coupl...