In this paper, the feasibility of a Control Moment Gyroscope (CMG) as balance assistance device is investigated. An inverted pendulum is used as experimental set-up. Our initial results show that it is possible to maintain balance within a 4 degrees range from vertical.

State-space methods are well adapted for solving stabilization problems. In the linear multivariable case, when the poles are placed, some degrees of freedom are left which can be used to place some zeros in the transfer functions from the perturbations to the outputs, called regulation zeros, to reject some perturbations. It is therefore interesting to use a suitable representation to compute ...

This paper analyzes the comfort of wheelchair users when a sliding-mode trajectory-tracking controller is used. The transmission of the horizontal (fore-and-aft) vibration to the head-neck complex (HNC) in the seated human body may cause unacceptable discomfort and motion sickness. A double-inverted pendulum model with two degrees of freedom is considered as a model for the HNC. The user comfor...

Class of axially symmetric solutions of vacuum Einstein field equations including the Papapetrou solution as particular case has been found. It has been shown that the derived solution describes the external axial symmetric gravitational field of the source with nonvanishing mass. The general solution is obtained for this class of functions. As an example of physical application, the spacetime ...

information retrieval can be achieved through computerized processes by generating a list of relevant responses to a query. the document processor, matching function and query analyzer are the main components of an information retrieval system. document retrieval system is fundamentally based on: boolean, vector-space, probabilistic, and language models. in this paper, a new methodology for mat...

The experimental uncertainties in G between different experiments have important implications for helioseismology. We show that these uncertainties for the standard solar model lead to a range in the value of the square of the sound speed in the nuclear region that is as much as 0.15% higher than the inverted helioseismic sound speed. While a lower value of G is preferred for the standard model...

This note describes two problems related to the digital implementation of control laws in the infinite dimensional family of matching control laws, namely state estimation and sampled data induced error. The entire family of control laws is written for an inverted pendulum cart. Numerical simulations which include sampled data and a state estimator are presented for one of the control laws in t...

We explain the physical effects involved in optical coupling in periodic structures which allow for photonic band gaps. We use a simple model to do this, since this allows us to establish some general principles for the operation of such devices. Further, we investigate the choice of parameters, with respect to the band gap, which will allow the device to operate suitably, and we contrast syste...