6R Instrumented Spatial Linkages for Anatomical Joint Motion Measurement—Part 1: Design

1992 ◽  
Vol 114 (1) ◽  
pp. 92-100 ◽  
Author(s):  
S. J. Kirstukas ◽  
J. L. Lewis ◽  
A. G. Erdman
Keyword(s):  
Numerical Methods ◽  
Design Process ◽  
Joint Motion ◽  
Calibration Technique ◽  
Knee Motion ◽  
Motion Measurement ◽  
Experimental Apparatus ◽  
The Subject ◽  
Spatial Linkages ◽  
Six Degree Of Freedom

Six-revolute-joint instrumented spatial linkages (6R ISLs) have become often-used devices to measure the complete six-degree-of-freedom motion of anatomical joints. Accuracy of motion measurement depends on ISL design and calibration technique. In this paper, a design process is outlined that uses computer graphics and numerical methods as aids in developing 6R ISLs that (i) physically assemble within the desired range of motion of the joint; (ii) do not collide with either the experimental apparatus or the subject joint; (iii) avoid singular linkage configurations that can cause forces to be applied to the joint; and (iv) measure selected anatomical motions most accurately. It is found that a certain subgroup of 6R linkages are suitable for accurate measurement of specific motions, and can be the basis for new ISL designs. General guidelines are developed that can assist in the generation of unique linkage designs for different anatomical joints. The design process is demonstrated in the creation of an ISL to measure knee motion.

6R Instrumented Spatial Linkages for Anatomical Joint Motion Measurement—Part 2: Calibration

1992 ◽  
Vol 114 (1) ◽  
pp. 101-110 ◽  
Author(s):  
S. J. Kirstukas ◽  
J. L. Lewis ◽  
A. G. Erdman
Keyword(s):  
Measuring System ◽  
Joint Motion ◽  
Electrical Parameters ◽  
Knee Motion ◽  
Anatomical Position ◽  
Calibration Algorithm ◽  
Calibration Device ◽  
Spatial Linkages ◽  
Six Degree Of Freedom ◽  
Interdependent Relationships

The six-revolute-joint instrumented spatial linkage (6R ISL) is often the measurement system of choice for monitoring motion of anatomical joints. However, due to tolerances of the linkage parameters, the system may not be as accurate as desired. A calibration algorithm and associated calibration device have been developed to refine the initial measurements of the ISL’s mechanical and electrical parameters so that the measurement of six-degree-of-freedom motion will be most accurate within the workspace of the anatomical joint. The algorithm adjusts the magnitudes of selected linkage parameters to reduce the squared differences between the six known and calculated anatomical position parameters at all the calibration positions. Weighting is permitted so as to obtain a linkage parameter set that is specialized for measuring certain anatomical position parameters. Output of the algorithm includes estimates of the measuring system accuracy. For a particular knee-motion-measuring ISL and calibration device, several interdependent design parameter relationships have been identified. These interdependent relationships are due to the configuration of the ISL and calibration device, the number of calibration positions, and the limited resolution of the devices that monitor the position of the linkage joints. It is shown that if interdependence is not eliminated, then the resulting ISL parameter set will not be accurate in measuring motion outside of the calibration positions, even though these positions are within the ISL workspace.

Joint Models, Degrees of Freedom, and Anatomical Motion Measurement

1983 ◽  
Vol 105 (1) ◽  
pp. 55-62 ◽  
Author(s):  
G. L. Kinzel ◽  
L. J. Gutkowski
Keyword(s):  
Measurement Technique ◽  
Degrees Of Freedom ◽  
Measurement Techniques ◽  
Kinematic Model ◽  
Joint Motion ◽  
Review Of The Literature ◽  
Joint Models ◽  
Motion Measurement ◽  
Six Degrees Of Freedom ◽  
Six Degree Of Freedom

When the motion associated with an anatomical joint is to be measured, a kinematic model for the joint must first be established. The joint model will have from one to six degrees of freedom, and both the measurement technique and the means used to describe the motion will be influenced by the model and its degrees of freedom. This paper discusses the modeling and measurement of anatomical joint motion from a kinematics viewpoint. A review of the literature pertaining to measurement techniques, kinematic assumptions, and motion descriptions for anatomical joint motion is presented. One, two, three and six degree-of-freedom models for various anatomical joints have appeared in the literature, and the applicability of these models is compared and discussed.

scholarly journals Engineering Design Driven by Models and Measures: The Case of a Rigid Inflatable Boat

2018 ◽  
Author(s):  
Cristiano Fragassa
Keyword(s):  
Numerical Methods ◽  
Engineering Design ◽  
Design Process ◽  
Experimental Approach ◽  
Numerical Models ◽  
Stress And Strain ◽  
Engineering Design Process ◽  
Hull Slamming ◽  
Available Information ◽  
Special Case

Rigid-hulled inflatable boats are extremely practical and popular nowadays. They offer a effective conciliation among usability and costs. Their stable and seaworthy behaviour is guaranteed by performing hydroplaning hulls coupled with unsinkable inflated tubes. At the same time, their design is often based on tradition and preconceptions. Rarely, the design assumptions are validated by the reality or, even, by deeper investigations. In this article, both numerical methods and experimental mechanics techniques are proposed as an essential way for supporting the designers in their decisive tasks. Three different situations are detailed where a numerical or an experimental approach shows its benefit inside the engineering design process: firstly permitting to investigate the behaviour of materials driving the fiberglass selection; then measuring the levels of stress and strain in the hull during sailing; finally, using all available information as a base for developing numerical models of the hull slamming in waves. Even if the discussion is focused on a rigid inflatable boat, large part of its considerations is relevant beyond this special case.

scholarly journals Making Things Right: New Zealand industrial design pioneer Peter Haythornthwaite, the quest for beauty and putting the user first

2021 ◽  
pp. 53-67
Author(s):  
Michael Barrett
Keyword(s):  
New Zealand ◽  
Design Process ◽  
Industrial Design ◽  
Small Contribution ◽  
Book Design ◽  
Design Generation ◽  
The Subject

In 2018, interviewing Peter Haythornthwaite for a small contribution to the book, ‘Design Generation’1 (by Michael Smythe; published in support of an Objectspace exhibition of the industrial designer’s work), the designer ventured on to the subject of beauty and its importance to his design process. It seems fitting to start here with that idea, because while beauty’s role in design is little discussed today, Haythornthwaite saw how objects of beauty make everyday use a delight.

scholarly journals Standardization and integration of the airport master plan design process

2018 ◽  
Vol 2018 (12) ◽  
pp. 77-86
Author(s):  
Michał Kozłowski
Keyword(s):  
Design Process ◽  
Dynamic Process ◽  
Practical Experience ◽  
Master Plan ◽  
Airport Management ◽  
Quality Of Results ◽  
The Subject ◽  
Effectiveness And Efficiency ◽  
Standard Documents

The article presents the conclusion of the practical experience as well as the results of the author's research in the field of airport management, formulated in the context of the implementation of the investment of the Central Polish Airport. The subject of the considerations and implications is the process of designing the Airport Master Plan – AMP, which in the current situation should be modified in order to ensure effectiveness and efficiency of implementation and quality of results. At the beginning, AMP was characterized on the basis of a study concerning legal acts and selected standard documents, and a study of the quality and risk issues of the AMP was carried out. On the basis of the results obtained, conclusions have been formulated regarding the need for standardization and integration of the dynamic process of AMP design.

“Tectonics” as a Spatial Perception Tool in the Design Process

2021 ◽  
pp. 1-20
Author(s):  
Ervin Garip ◽  
Ceren Çelik
Keyword(s):  
Design Process ◽  
Interior Design ◽  
Spatial Perception ◽  
Main Idea ◽  
Architectural Elements ◽  
Space Design ◽  
New Ideas ◽  
The Subject ◽  
New Perspective ◽  
Interior Design Students

Design process has its own structure which is affected by many aspects. Moreover, there are many tools that contribute in this multidimensional process. Within the framework of this chapter, the tectonics is suggested as a directive tool through the design process. Istanbul Technical University Interior Design students' second year studio, where tectonics was used as a spatial perception tool, was examined. The main title of the studio was festival space design, where festivals were discussed as a performance scene for urban interiors. The main idea of suggested method is to consider environmental aspects in different scales and project those findings to tectonics. The main purpose of this project is to create a new perspective to interior design studio approach. The subject of the project was shaped within the framework of testing that interior architecture is not independent from architectural elements contextually and phenomenologically and that environmental decisions and architectural tectonics can be used as a data to put forth the new ideas for interior design methodology.

“Premierløytnant Bielke”

2011 ◽  
pp. 117-133
Author(s):  
Jo Dugstad Wake ◽  
Rune Baggetun
Keyword(s):  
Mobile Phone ◽  
Design Process ◽  
Mobile Phones ◽  
Computer Games ◽  
Teaching And Learning ◽  
Research Interest ◽  
Mobile Location ◽  
Mobile Phone Technology ◽  
Learning History ◽  
The Subject

Developments in mobile phone technology, together with an increased research interest in utilizing computer games to facilitate teaching and learning, are an important catalyst for the emergence of the area of mobile, location-based computer games in schools. This article describes both the design process and an evaluation of Premierløytnant Bielke, a mobile, location-based game for teaching and learning history using mobile phones. We argue that by using the surroundings and milieu that are local to the students in a playful context, we can support the construction of meaning related to the subject of history in a way that is both engaging and worthwhile.

Explanation in Prehistory

1971 ◽  
Vol 37 (1) ◽  
pp. 38-55 ◽  
Author(s):  
J. C. Harriss
Keyword(s):  
Numerical Methods ◽  
Academic Discipline ◽  
Well Being ◽  
Natural Sciences ◽  
Prehistoric Archaeology ◽  
Methods And Techniques ◽  
The Subject

Jacquetta Hawkes in a paper called ‘The Proper Study of Mankind’ (Hawkes, 1968) has made an impassioned plea against what she considers to be the ‘dehumanization’ of prehistory at the hands of those who have sought to apply to it numerical methods and the techniques of the natural sciences. There can be few who do not sympathize with her denunciation of aimless manipulation of data and the use of techniques for their own sakes; and many must share Clark's fear that prehistoric archaeology will serve merely ‘… to provide intellectual games for the meritocracy’ (Clark, 1967, 472). But such comments as these only prompt the question ‘what are we studying prehistory for?’ or ‘what is prehistory about?’The well-being of any academic discipline depends upon the posing of questions like these, for if a subject is to develop at all, it must undergo periods of self-analysis when some of its practitioners take stock of what they themselves and others are doing. The analysis may be concerned with methods and techniques and may either tacitly or openly accept the existing philosophy. Or it may consider the philosophy of the subject directly, by asking if the priorities of a past age are still acceptable or whether in the different climate of thought of the present, they must be changed. Self-analysis of this kind may however produce a state of unease and disquiet.

Effect of Dynamic Changes in Anterior Cruciate Ligament In Situ Graft Force on the Biological Healing Response of the Graft-Tunnel Interface

2018 ◽  
Vol 46 (4) ◽  
pp. 915-923 ◽  
Author(s):  
Richard Ma ◽  
Michael Schär ◽  
Tina Chen ◽  
Marco Sisto ◽  
Joseph Nguyen ◽  
...  
Keyword(s):  
Anterior Cruciate Ligament ◽  
Acl Reconstruction ◽  
Cruciate Ligament ◽  
Male Rats ◽  
Joint Motion ◽  
Dynamic Changes ◽  
Knee Motion ◽  
Acl Graft ◽  
Anterior Cruciate

Background: Anterior cruciate ligament (ACL) grafts that are placed for reconstruction are subject to complex forces. Current “anatomic” ACL reconstruction techniques may result in greater in situ graft forces. The biological effect of changing magnitudes of ACL graft force on graft-tunnel osseointegration is not well understood. Purpose: The research objective is to determine how mechanical force on the ACL graft during knee motion affects tendon healing in the tunnel. Study Design: Controlled laboratory study. Methods: Male rats (N = 120) underwent unilateral ACL reconstruction with a soft tissue flexor tendon autograft. ACL graft force was modulated by different femoral tunnel positions at the time of surgery to create different graft force patterns with knee motion. External fixators were used to eliminate graft load during cage activity. A custom knee flexion device was used to deliver graft load through controlled daily knee motion. Graft-tunnel healing was then assessed via biomechanical, micro–computed tomography, and histological analyses. Results: ACL graft-tunnel healing was sensitive to dynamic changes in graft forces with postoperative knee motion. High ACL graft force with joint motion resulted in early inferior ACL graft load to failure as compared with knees that had low-force ACL grafts and joint motion and knees that were immobilized (mean ± SD: 5.50 ± 2.30 N vs 9.91 ± 3.54 N [ P = .013] and 10.90 ± 2.8 N [ P = .001], respectively). Greater femoral bone volume fraction was seen in immobilized knees and knees with low-force ACL grafts when compared with high-force ACL grafts at 3 and 6 weeks. Conclusion: The authors were able to demonstrate that ACL graft-tunnel incorporation is sensitive to dynamic changes in ACL graft force with joint motion. Early high forces on the ACL graft appear to impair graft-tunnel osseointegration. Clinical Relevance: Current “anatomic” techniques of ACL reconstruction may result in greater graft excursion and force with knee motion. Our results suggest that the postoperative rehabilitation regimen may need to be modified during the early phase of healing to protect the reconstruction.

Real-Time Multi-Body Software for HIL Simulations

2010 ◽  
Author(s):  
Paolo Righettini ◽  
Alberto Oldani
Keyword(s):  
Mathematical Model ◽  
Embedded Systems ◽  
Design Process ◽  
Hardware In The Loop ◽  
Real Behavior ◽  
Hardware Component ◽  
General Mathematical Model ◽  
The Subject ◽  
Complex Mechanical Systems ◽  
Multi Body

The Hardware in the Loop simulation is an useful instrument to simulate complex mechanical systems in which the subject of the test is an hardware component. The results of the simulation, closer to the real behavior of the system, are the main advantage of this approach. This application is often used during the design process to test components of a complex mechanical system before the development of the prototype (e.g. embedded systems). The literature examples show, in general, mathematical model finalized to the application. The objective of this work is focused on the development of a generic Multi-Body software for HIL applications. Some simulations examples, the dynamic of a slider-crank and of a McPherson suspension, are presented at the end of the paper.

Sign in / Sign up

Export Citation Format

Share Document