Two different nonlinear dynamic control algorithms are presented for synchronous motors with damping windings: (i) an adaptive speed-sensorless controller for rotor position tracking in the presence of unknown constant load torque, on the basis of rotor angle, stator and field windings currents measurements; (ii) an adaptive control law for rotor speed tracking in the presence of uncertain cons...

If the rotational vestibuloocular reflex (VOR) were to achieve optimal retinal image stabilization during head rotations in three-dimensional space, it must turn the eye around the same axis as the head, with equal velocity but in the opposite direction. This optimal VOR strategy implies that the position of the eye in the orbit must not affect the VOR. However, if the VOR were to follow Listin...

As airplane designs have trended toward the expansion of flight envelopes into the high angle of attack and high angular rate regimes, concerns regarding modeling the complex unsteady aerodynamics for simulation have arisen. Most current modeling methods still rely on traditional body axis damping coefficients that are measured using techniques which were intended for relatively benign flight c...

Passive stabilization methods for satellites have undergone extensive research and development. Recently the number of small satellites (satellites less than I 00 kg.) has increased dramatically. This has lead to increased use of passive stabilization methods, such as gravity-gradient The core of a gravity-gradient stabilization system is a deployable boom with a damping mechanism. Traditionall...

We prove that the angular velocity equations can be smoothly stabilized with a single torque controller for bodies having an axis of symmetry. This complements a recent result of Aeyels and Szafranski.

Nowadays, the use of small vehicles is spreading among urban areas and one sort of these vehicles are three-wheeled vehicles (TWVs) which can be competitive with four-wheeled urban vehicles (FWVs) in aspects such as smallness, simple manufacturing, and low tire rolling resistance, fuel consumption and so on. The most critical instability associated with TWVs is the roll over. In this paper a ti...

This article presents a solution to the path following problem for the planar vertical take-off and landing aircraft (PVTOL) which is applicable to a class of smooth Jordan curves. Our path following methodology enjoys the two properties of output invariance of the path (i.e., if the PVTOL’s centre of mass is initialized on the path and its initial velocity is tangent to the path, then the PVTO...

For experiments at the torque meter, flies are kept on standard fly medium at 25 degrees C and 60% humidity with a 12hr light/12hr dark regime. A standardized breeding regime assures proper larval density and age-matched cohorts. Cold-anesthetized flies are glued with head and thorax to a triangle-shaped hook the day before the experiment. Attached to the torque meter via a clamp, the fly's int...

Joint friction is a major problem in accurately controlling manipulators performing small precise tasks. Previously developed solutions to this problem require the use of either complex and unreliable models of the joint friction or expensive and delicate internal joint torque sensors. Here a simple, cost-effective method for compensating the effect of joint friction is proposed. It uses a six-...

PURPOSE The purpose of this study was to compare internal Morse taper connections in 2 separate modes: repeated torque/reverse-torque values and compressive bending at a 30-degree off-axis angle. MATERIALS AND METHODS Three sample groups (n = 12 in each group)--a solid-screw implant paired with a 5.5-mm solid abutment (SSI), a synOcta implant with a 5.5-mm solid abutment (SOI), and a synOcta ...