Kinematics analysis of 6-DOF parallel micro-manipulators with offset U-Joints : a case study

This paper analyses the kinematics of a special 6-DOF parallel micro-manipulator with offset RR-joint configuration. Kinematics equations are derived and numerical methodologies to solve the inverse and forward kinematics are presented. The inverse and forward kinematics of such robots compared with those of 6-UCU parallel robots are more complicated due to the existence of offsets between joints of RR-pairs. The characteristics of RR-pairs used in this manipulator are investigated and kinematics constraints of these offset U-joints are mathematically explained in order to find the best initial guesses for the numerical solution. Both inverse and forward kinematics of the case study 6-DOF parallel micro-manipulator are modelled and computational analyses are performed to numerically verify accuracy and effectiveness of the proposed methodologies.

Kinematics analysis of 6-DOF parallel micro-manipulators with offset u-joints : a case study

This paper analyses the kinematics of a special 6-DOF parallel micro-manipulator with offset RR-joint configuration. Kinematics equations are derived and numerical methodologies to solve the inverse and forward kinematics are presented. The inverse and forward kinematics of such robots compared with those of 6-UCU parallel robots are more complicated due to the existence of offsets between joints of RR-pairs. The characteristics of RR-pairs used in this manipulator are investigated and kinematics constraints of these offset U-joints are mathematically explained in order to find the best initial guesses for the numerical solution. Both inverse and forward kinematics of the case study 6-DOF parallel micro-manipulator are modelled and computational analyses are performed to numerically verify accuracy and effectiveness of the proposed methodologies.

Fly rhythm

This book contains 2 essays, a forward and 15 colour plates on hand made paper. The text supports research in the form of 13 images taken with a digital pinhole camera in an unconventional way ie with subject and author in motion.  The images are further removed from traditional photography by light distribution in Photoshop and printing methods displayed in the book. The essays and forward explore the phenomena of light, photography in a digital age, body memory and 'capture' of images contextualising the work in philosophical (Rosalind Krauss,Merleau Ponty) and art historical (James Turrel, Doug Wheeler) terms.

Patient participation in nursing care on medical wards: An integrative review

BACKGROUND: Patient participation is a way for patients to engage in their nursing care. In view of the possible link between patient participation and safety, there is a need for an updated review to assess patient participation in nursing care. OBJECTIVES: To investigate patients' and nurses' perceptions of and behaviours towards patient participation in nursing care in the context of hospital medical wards. DESIGN: Integrative review. DATA SOURCES: Three search strategies were employed in August 2013; a computerised database search of Cumulative Index of Nursing and Allied Health Literature, Cochrane Library, Medline and PsychINFO; reference lists were hand-searched; and forward citation searching was executed. REVIEW METHODS: After reviewing the studies, extracting study data and completing summary tables the methodological quality was assessed using the Mixed-Methods Assessment Tool by two reviewers. Reviewers met then to discuss discrepancies as well as the overall strengths and limitations of the studies. Discrepancies were overcome through consensus or a third reviewer adjudicated the issue. Within and across study analysis and synthesis of the findings sections was undertaken using thematic synthesis. RESULTS: Eight studies met inclusion criteria. Four themes were identified - enacting participation, challenges to participation, promoting participation and types of participation. Most studies included were conducted in Europe. The majority of studies used qualitative methodologies, with all studies sampling patients; nurses were included in three studies. Data were largely collected using self-reported perceptions; two studies included observational data. Methodological issues included a lack of reflexivity, un-validated data collection tools, sampling issues and low response rates. CONCLUSIONS: On medical wards, patients and nurses desire, perceive or enact patient participation passively. Challenging factors for patient participation include patients' willingness, nurses' approach and confusion around expectations and roles. Information-sharing was identified as an activity that promotes patient participation, suggesting nurses encourage active communication with patients in practice. Involving patients in assessment and care planning may also enhance patient participation. For education, enhancing nurses' understanding of the attributes of patient participation, as well as patient-centred care approaches may be beneficial for medical ward nurses. From here, researchers need to examine ways to overcome the barriers to patient participation; further nurse participants and observational data is required on medical wards.

The influence of various seat design parameters: a computational analysis

Nowadays, low back pain becomes a common healthcare problem. Poor or unsuitable seat design is related to the discomfort and other healthcare problems of users. The aim of this study is to investigate the influence of seat design variables on the compressive loadings of lumbar joints. A basis that includes a musculoskeletal human body model and a chair model has been developed using LifeMOD Biomechanics Modeller. Inverse and forward dynamic simulations have been performed for various seat design parameters. The results show that the inclination of backrest and seat pan may or may not decrease the compressive spinal joint forces, depending on other conditions. The medium-level height and depth of seat pan and the medium-level and high-level height of backrest are found to cause the minimum compressive loads on lumbar joints. This work contributes to a better understanding of sitting biomechanics and provides some useful guidelines for seat design.

Mathematical modelling of linear motion error for Hexarot parallel manipulators

Hexarot is a robotic manipulator that belongs to the family of axis symmetric parallel mechanisms. The robot is able to move the robot platform or tool center point in six degrees of freedom (DOF). This paper presents the kinematics model of the robot including the inverse and forward kinematics, and its time derivatives. Then using the kinematics formulations, investigation of the nonlinear motion of the Hexarot robot for a desired linear motion path is performed. For this purpose, the concept of curvature of the robot path is used for measuring the nonlinearity of the actual motion of the robot. The nonlinear motion error of the robot is analyzed for the scenario where the platform moves on a linear path between two arbitrary points of the robot workspace. The effects of different parameters on the nonlinear motion error of the mechanism are demonstrated and strategies for motions with low error values are proposed.

Input–output structures of the Australian construction industry

The Australian construction industry continues to play an important role in the national economy. Analysis using input–output tables makes it possible to understand the role of the construction industry in Australia’s economy and its relationships to other major industries over years. This study applies several economic indicators to investigate the construction industry’s contributions to gross national product and gross national income, as well as its backward and forward linkage indicators, and its output and input multipliers. The paper also investigates the purchases of goods and services by the construction industry from other sectors and its sales to other industries over the analysis period. Findings from this research may help policymakers to better understand the economic linkages between the construction industry and other major industries, and the structural changes in its inputs and outputs in relation to these others.

SER analysis of multi-way relay networks with M-QAM modulation in the presence of imperfect channel estimation

Multi-way relay networks (MWRNs) allow multiple users to exchange information with each other through a single relay terminal. MWRNs are often incorporated with capacity achieving lattice codes to enable the benefits of high-rate signal constellations to be extracted. In this paper, we analytically characterize the symbol error rate (SER) performance of a functional decode and forward (FDF) MWRN in the presence of channel estimation errors. Considering Μ-ary quadrature amplitude modulation(QAM) with square constellations as an important special case of lattice codes, we obtain asymptotic expressions for the average SER for a user in FDF MWRN. The accuracy of the analysis at high signal-to-noise ratio is validated by comparison with the simulation results. The analysis shows that when a user decodes other users with better channel conditions than itself, the decoding user experiences better error performance. The analytical results allow system designers to accurately assess the non-trivial impact of channel estimation errors and the users’ channel conditions on the SER performance of a FDF MWRN with M-QAM modulation.

Error performance analysis of a clustered multiway relay network

In this paper, we propose a new clustered structure for a multiway relay network (MWRN) with G clusters, N users per cluster, one intracluster relay per cluster, and a single intercluster relay. The proposed structure allows private information exchange among users within a certain cluster through the corresponding intracluster relay and only public information exchange among users in different clusters through the intercluster relay.In this paper, we quantify the dominating error events in the proposed clustered MWRN and derive the expressions for the probability of these error events. Then, we use these expressions to derive the average bit error rate (BER) of a clustered MWRN. It is shown that clustering in an MWRN improves the error performance by reducing the number of dominating error events and, in effect, reducing error propagation, compared with the nonclustered counterpart. The analysis proves that the average BER of a clustered MWRN is minimized when the number ofclusters and the number of users per cluster are chosen to be the closest possible factors of the total number of users, i.e., L = GN. Finally, numerical simulation results are provided to verify the validity of the analysis.

Predatory pricing and the expectation of recoupment in Australia : Boral and the pathways forward

High Court decision, Boral v ACCC in which the Court overturned the decision of the Full Federal Court and held that Boral's strategy of below cost pricing did not contravene s 46 of the Trade Practices Act - suggestion that the test of recoupment be the central test with respect to predatory pricing cases.

Charges over book debts in the United Kingdom and Australia : the way forward

Is it possible to create a fixed charge over book debts? This question was recently decided by the House of Lords in National Westminster Bank plc v. Spectrum Plus Limited & Ors [2005] UKHL 41 where the full House was against the idea of a fixed charge on book debts and insisted that only a
floating charge had been created. The law in this area is still vague and uncertain in Australia. This article argues that the financiers and the companies should be given the freedom to decide how they wish to structure their charge documents. The article sets out to argue that it is possible to create a sustained workable fixed charge or even a multiple combination of fixed and floating charge over book debts and argues that this would be the only way for both the financiers and the companies to do business together, in respect to the use of book debts as security for a loan. The author explains how this could be possible and how the proposed model would not deny the statutory priority rights of the preferential creditors.

A need for national regulation on property investment advice and marketeering - suggestions put forward

The property investment advice and marketeering industry is currently unregulated in Australia. There is no uniform national or state regulation in this area. The only protection and remedies currently available are those under the general consumer protection laws scattered in various Acts, and even so, these have numerous problems.This article sets out to argue for a new set of laws to regulate property investment advice and marketeering. In providing suggestions for reform, the article also argues that, to overcome the constitutional difficulty, a national co-operative approach is the only way to move forward in this area and suggests that a new regulator be set up to administer and enforce the new proposed laws on property investment advice and marketeering.