GPS-guided mobile robot platform featuring modular design elements for agricultural applications : a thesis presented in partial fulfilment of the requirements for the degree of Masters of Engineering in Mechatronics at Massey University Turitea Campus, Palmerston North, New Zealand

The agricultural industry has not seen significant innovation in development of low-cost automated farming solutions, with current systems costing several thousands of dollars to implement. Currently these automated solutions are primarily implemented around crop planting and harvesting, and the large implementation cost of these systems makes them unfeasible for small-scale operations. Within many agricultural industries, workers expend a considerable amount of time undertaking simple tasks that are labour intensive. Many of these tasks could instead be completed using a self-driving robotic platform outfitted with the appropriate devices required for the tasks. This thesis covers the research work aiming to produce a solution that could turn an existing farming vehicle into a multipurpose low-cost agricultural platform, to act as the platform for an autonomous vehicle capable of performing pre-programmed tasks within an agricultural environment. A quad bike was selected as the vehicle platform for this research in which the control modules would control the speed and direction of this farm bike. Four modules were developed to control the vehicle components that would normally be operated by a human operator. These modules are comprised of mechanical actuators coupled with a microcontroller control system and includes some specific designs to maintain the user's ability to manually control the pre-existing systems. A gear-changing module controls the vehicles manual gearbox, providing a method to detect and control the vehicles current gear. A speed control module was developed to control the vehicles throttle and braking system and detects the vehicles speed. A steering module controls the vehicles steering system, allowing for accurate control of the vehicles direction. Finally, a vehicle controller module provides a central command interface that ties the previous three modules together and controls the vehicles electrical components and engine. Development of a low-cost differential GPS (DGPS) system was also undertaken to reduce the implementation cost of the system. Due to inconclusive results in relation to the positional accuracy of this system is was decided that a standard GPS system would be used for the vehicle prototype with further development on the DGPS system would be undertaken in future development of the research. The successful development of a farm automated vehicle platform was achieved through this research. With further improvement on software, intelligent control and the development of a low-cost differential global positioning satellite (GPS) system, a fully autonomous farm platform that can be outfitted with different tools or devices for the required farm tasks is feasible and practical

Exploiting connectedness in the informatics curriculum

The power of modern communication technology gives us an opportunity, as Informatics educators, to enhance our ability to develop our students' skills in virtual teamworking. We discuss why virtual teamworking is as relevant for students in traditional campus-based universities as it is in a distance learning context. We highlight some of the questions to be answered, and some of the problems to be overcome, in the context of our experiences in designing and delivering a virtual teamworking course at the UK Open University

An analysis of consumer panel data

In terms of collecting comprehensive panel expenditure data, there are trade-offs to be made in terms of the demands imposed on respondents and the level of detail and spending coverage collected. Existing comprehensive spending data tends to be cross-sectional whilst panel studies include only limited expenditure questions that record spending only as broad aggregates. More recently, economists have begun to use spending information collected by market research companies that records very detailed spending down to the barcode level from a panel of households, usually recorded by in-home barcode scanners, which may provide considerable advantages over existing data more commonly used in social sciences. However, there has not been a comprehensive assessment of the strengths and weaknesses of this kind of data collection method and the potential implications of survey mode on the recorded data. This paper seeks to address this, by an in-depth examination of scanner data from one company, Taylor Nelson Sofres (TNS), on grocery purchases over a five-year period. We assess how far the ongoing demands of participation inherent in this kind of survey lead to 'fatigue' in respondents' recording of their spending and compare the demographic representativeness of the data to the well-established Expenditure and Food Survey (EFS), constructing weights for the TNS that account for observed demographic differences. We also look at demographic transitions, comparing the panel aspect of the TNS to the British Household Panel Study (BHPS). We examine in detail the expenditure data in the TNS and EFS surveys and discuss the implications of this method of data collection for survey attrition. Broadly, we suggest that problems of fatigue and attrition may not be so severe as may be expected, though there are some differences in expenditure levels (and to some extent patterns of spending) that cannot be attributed to demographic or time differences in the two surveys alone and may be suggestive of survey mode effects. Demographic transitions appear to occur less frequently than we might expect which may limit the usefulness of the panel aspect of the data for some applications

Developing Online Team Skills

This paper discusses the development and delivery of a new course at the UK Open University (OU). The course makes a virtue of the fact that OU students study in a predominantly distance learning environment, by providing a structure within which team working activities are carried out with no face-to-face contact whatsoever. Issues that were considered in designing this course and decisions about tutoring and assessing the students' team working experience are discussed. Preliminary results from the first delivery of the course, including analysis of archived team conferences, are presented. Directions for future development and enhancement are indicated

An analysis of consumer panel data

In terms of collecting comprehensive panel expenditure data, there are trade-offs to be made in terms of the demands imposed on respondents and the level of detail and spending coverage collected. Existing comprehensive spending data tends to be cross-sectional whilst panel studies include only limited expenditure questions that record spending only as broad aggregates. More recently, economists have begun to use spending information collected by market research companies that records very detailed spending down to the barcode level from a panel of households, usually recorded by in-home barcode scanners, which may provide considerable advantages over existing data more commonly used in social sciences. However, there has not been a comprehensive assessment of the strengths and weaknesses of this kind of data collection method and the potential implications of survey mode on the recorded data. This paper seeks to address this, by an in-depth examination of scanner data from one company, Taylor Nelson Sofres (TNS), on grocery purchases over a five-year period. We assess how far the ongoing demands of participation inherent in this kind of survey lead to 'fatigue' in respondents' recording of their spending and compare the demographic representativeness of the data to the well-established Expenditure and Food Survey (EFS), constructing weights for the TNS that account for observed demographic differences. We also look at demographic transitions, comparing the panel aspect of the TNS to the British Household Panel Study (BHPS). We examine in detail the expenditure data in the TNS and EFS surveys and discuss the implications of this method of data collection for survey attrition. Broadly, we suggest that problems of fatigue and attrition may not be so severe as may be expected, though there are some differences in expenditure levels (and to some extent patterns of spending) that cannot be attributed to demographic or time differences in the two surveys alone and may be suggestive of survey mode effects. Demographic transitions appear to occur less frequently than we might expect which may limit the usefulness of the panel aspect of the data for some applications.Household panel data, scanner data, expenditure, food, duration models, attrition

Differences in the measurement and structure of wealth using alternative data sources: the case of the UK

In this paper, we identify methodological differences and similarities in the measurement of wealth using survey data constructed for different purposes in the United Kingdom and England. The focus of the paper is on two prominent surveys in the UK: the English Longitudinal Survey of Ageing (ELSA) and the British Household Panel Survey (BHPS). We find conceptual difference in the measurement of financial assets and debt. At the same time, striking similarities exist in the measurement of non-financial assets. For the most part, many differences arise in the tails of the distributions of wealth. Comparable definitions of overall wealth in the surveys lead us to find a 10% and 3% difference in mean and conditional median of total net worth, respectively. Reassuring is the fact that inequality results carried out with the two surveys support one another and quantile regression shows that the distribution of total net worth across demographic groups is similar in the two surveys.

The inflation experience of older households

Recent increases in inflation have been accompanied by concerns over the extent to which official figures match the 'true' household experience of inflation. Rapid increases in the prices of household fuel, petrol and diesel and, more recently, of food have brought considerable attention to the fact that inflation will be different for different households according to their expenditure patterns. Any measure of inflation, such as the Retail Prices Index (RPI) or Consumer Prices Index (CPI), is necessarily only an average of the experience of different households and may not be especially representative of what is happening for any household in particular. Using data from the Expenditure and Food Survey, this Commentary looks at the inflation experience (based on the RPI) for different groups of households, examining how the average inflation rate they face has varied over time and making comparisons across the groups, focusing in particular on pensioner households

The expenditure experience of older households

This commentary examines detailed trends in expenditure patterns between 1995 and 2007, with a particular focus on the pensioner population. Pensioners are not a homogeneous group, but differ widely in both their levels and patterns of spending, and so we look not just at pensioners as a whole but also at pensioners according to age, income, household composition and so on. Spending may tell us something about household welfare that other, often-used measures like incomes do not. In particular, it may be that spending is informative about long-run well-being whereas income is more about current, short-run living standards. Using data from the Family Expenditure Survey/Expenditure and Food Survey, an annual, cross-sectional study of the spending patterns of 6,000-7,000 households, we look in depth at changes in the level of real expenditures and how spending patterns have changed over time. Then, using data from two waves of the English Longitudinal Study of Ageing, we examine household fuel expenditures in detail. Fuel is clearly of great current policy concern given recent large increases in the price of domestic fuel that may impact particularly severely on poorer and older households

Encountering soviet geography: oral histories of British geographical studies of the USSR and Eastern Europe 1945-1991

This paper considers the history of British geographical studies of the USSR and Eastern Europe 1945-1991, presenting material from a research project which has included thirty-two oral history interviews. Oral history is an especially fruitful research methodology in this context due to the distinct issues of formality and informality involved in researching the Soviet bloc. After discussing the nature of the subdiscipline and the Cold War context, including the role of the British state in shaping the field, the paper considers the role of formal academic meetings and exchanges, and the place of unofficial spaces of encounter in the formation of an intellectual culture. The paper concludes by reflecting on the merits of oral history in studies of the production of geographical knowledge