To measure the motions of the trapeziometacarpal joint of the thumb quantitatively, a roentgenographic method was developed and tested using T-shaped metal markers, a special cassette-holder, and biplane roentgenograms. Two experiments were performed. In the first one, the metal markers were fixed to the trapezium and third metacarpal in ten cadaver specimens, and a fixed spatial relationship b...

background: evaluating the landmarks for rotation of the distal femur is a challenge for orthopedic surgeons. although the posterior femoral condyle axis is a good landmark for surgeons, the surgical transepicondylar axis may be a better option with the help of preoperative ct scanning. the purpose of this study was to ascertain relationships among the axes’ guiding distal femur rotational alig...

The current hypothesis regarding the mechanics of breathing in crocodylians is that the double-headed ribs, with both a capitulum and tuberculum, rotate about a constrained axis passing through the two articulations; moreover, this axis shifts in the caudal thoracic ribs, as the vertebral parapophysis moves from the centrum to the transverse process. Additionally, the ventral ribcage in crocody...

A simple external marker system and algorithms for computing lower extremity joint angle motion during level walking were developed and implemented on a computer-aided video motion analysis system (VICON). The concept of embedded axes and Euler rotation angles was used to define the three-dimensional joint angle motion based on a set of body surface markers. Gait analysis was performed on 40 no...

BACKGROUND AND PURPOSE Whether tibial torsion affects the positioning of extramedullary instrumentation and is a possible factor in malalignment of the tibial component in total knee arthroplasty (TKA) is unknown. We assessed the influence of tibial torsion on distal alignment of extramedullary systems for TKA, using the center of the intermalleolar distance as anatomical reference at the ankle...

This reports documents work undertaken in optimising a kinematic model of the human thumb. It is motivated by the high rejection rate observed with myoelectric hand prostheses, which increases with the period of wear and can reach 50% after 5 years. We find that the most commonly-cited reasons for rejecting a prosthesis are its weight, slow actuation speed, and poor durability, whereas the cosm...

arch dams are generally built in cantilvever monoliths. vertical contraction joints between monoliths control the stresses due to concrete shrinkage and temperature variations. past studies in earthquake safety evaluation of the system often show the tensile fracture and local nonlinear deformation of joints. in this paper, some nonlinear joint element constitutive models are presented to exami...

A natural interaction with virtual environments is one of the key issues for the usability of Virtual Reality applications. Device-free, intuitive interactions with the virtual world can be achieved by capturing the movements of the user with markerless motion capture. In this work we present a markerless motion capture approach which can be used to estimate the human body pose in real-time wit...

The goal of this research is to develop algorithms using multiple views to automatically recover complete 3D models of articulated objects in unstructured environments and thereby enable a robotic system to facilitate further manipulation of those objects. First, an algorithm called Procrustes-Lo-RANSAC (PLR) is presented. Structure-from-motion techniques are used to capture 3D point cloud mode...

In this study, analytical models considering different material and geometry for ‎both single and double-lap bolted joints were reviewed for better understand how to ‎select the proper model for a particular application. The survey indicades that the ‎analytic models selected for the adhesively single or double bolted lap joints, as well ‎as T, scarf, and stepped joints, with linear material pr...