The grand piano action has been developped empirically and provides a remarkably accurate control of the hammer velocity and the impact time [1]. The numerical simulation of the action is necessary to improve numerical keyboards and to better understand haptic controllability. Following previous efforts [2, 3], we propose a simulation based on an explicit model and a solver of non-smooth dynami...

With its portable, simple and affordable attributes, the Schmidt hammer (SH) is an ideal index apparatus, which underlies its increasing popularity and expanding range of applications. The SH rebound hardness value (R) is perhaps the most frequently used index in rock mechanics practice for estimating the uniaxial compressive strength (UCS) and the modulus of elasticity (E) of intact rock both ...

We previously presented an image registration method, referred to hierarchical attribute matching mechanism for elastic registration (HAMMER), which demonstrated relatively high accuracy in inter-subject registration of MR brain images. However, the HAMMER algorithm requires the pre-segmentation of brain tissues, since the attribute vectors used to hierarchically match the corresponding pairs o...

Three new species of oribatid mites of the family Oppiidae (Oribatida, Oppioidea), belonging to the genera/subgenera Tripiloppia Hammer, 1968 and Lanceoppia (Baioppia) Luxton, 1985, are described from Central Otago, South Island, New Zealand. Tripiloppia frigida sp. nov. is morphologically similar to T. dalenii Hammer, 1968, but differs from the latter by the lanceolate bothridial setae, five p...

In order to find all intersections among polygonal chains, this paper presents a procedure consisting of two phases: (1) splitting polygonal chains into a minimal number of monotone chains and (2) finding intersections among the monotone chains. For the first phase, we suggest an optimal algorithm splitting polygonal chains into a minimal number of monotone chains, with an Oðn þ r log rÞ time c...

In this paper, we reexamine in the framework of robust computation the BentleyOttmann algorithm for reporting intersecting pairs of segments in the plane. This algorithm has been reported as being very sensitive to numerical errors. Indeed, a simple analysis reveals that it involves predicates of degree 5, presumably never evaluated exactly in most implementation. Within the exact-computation p...

Hydrodynamics of the manipulator mounted on the vehicle are poorly known and time-varying. Furthermore, its motion is disturbed by the vehicle motion and current. This paper presents a non-regressor based adaptive control scheme with a disturbance observer for tracking the trajectory of underwater mobile platform-mounted manipulators. The presented control system does not require any informatio...

Abstract: The extended state observer first proposed by Jingqing Han in [J. Q. Han, The extended state observer for a class of uncertain systems, Control and Decision, 10(1)(1995), 85-88] is the main interim loop of active disturbance rejection control that is taking off as a technology after numerous successful applications in engineering. Unfortunately, there is no a rigorous proof of converg...