title: Transferable semi-autonomous architecture for vehicles operating in corridor crop environments

authors: Tobias, Jonathan Isaac

subjects: Semi-autonomous

abstract: The role of autonomous vehicles (AVs) in assisting people is recognised and, therefore, is in constant development in numerous fields. Specifically, AV’s ability to alleviate global stressors, including an increased potential for food shortages and the decline in workers for potentially laborious work. An area where AVs developments are particularly prevalent is in agriculture. However, the few AVs being used in agriculture are often custom built for specific purposes and require large development time as a result. This thesis aims to build and evaluate a versatile architecture that can be transferred to any agricultural vehicle, thus decreasing the development time.

This thesis presents a novel architecture known as a semi-autonomous architecture (SAA). The research involved investigating and incorporating specific sensors, and also developing a common software module to perform the localisation, navigation and mapping particularly suited for corridor crop agricultural environment. This architecture was integrated and implemented on a Yamaha golf cart, infusing it with purposely positioned sensors and supportive electronics to allow a Robotic Operating System (ROS) framework to gather information and control the vehicle. As the architecture is modular in nature, it can be transferred to different customised platforms.

To determine the efficacy of the SAA, the platform went through a field trial and simulations to test the fundamentals of an agricultural AV. This meant investigating the SAA’s ability to map, plan paths, avoid obstacles and maintain a specific distance from a row. The evaluation demonstrated that both ’RTAB-Map’ and ’Gmapping’ could produce accurate maps of a vineyard. Additionally, grid-based planners, such as Dijkstra and A*, performed better than a sample-based planner bias-IRRT*. Regarding obstacle avoidance, the SAA required a greater range of sensors to detect small and oddly shaped objects that could be found in a vineyard. The SAA maintained within 5mm of the specified distance when aiming to follow the row. The results from these experiments demonstrated the SAA’s ability to successfully transform a Yamaha golf cart into a semi-autonomous agricultural vehicle.

text: Transferable semi-autonomous architecture for vehicles operating in corridor crop environments The role of autonomous vehicles (AVs) in assisting people is recognised and, therefore, is in constant development in numerous fields. Specifically, AV’s ability to alleviate global stressors, including an increased potential for food shortages and the decline in workers for potentially laborious work. An area where AVs developments are particularly prevalent is in agriculture. However, the few AVs being used in agriculture are often custom built for specific purposes and require large development time as a result. This thesis aims to build and evaluate a versatile architecture that can be transferred to any agricultural vehicle, thus decreasing the development time.

This thesis presents a novel architecture known as a semi-autonomous architecture (SAA). The research involved investigating and incorporating specific sensors, and also developing a common software module to perform the localisation, navigation and mapping particularly suited for corridor crop agricultural environment. This architecture was integrated and implemented on a Yamaha golf cart, infusing it with purposely positioned sensors and supportive electronics to allow a Robotic Operating System (ROS) framework to gather information and control the vehicle. As the architecture is modular in nature, it can be transferred to different customised platforms.

To determine the efficacy of the SAA, the platform went through a field trial and simulations to test the fundamentals of an agricultural AV. This meant investigating the SAA’s ability to map, plan paths, avoid obstacles and maintain a specific distance from a row. The evaluation demonstrated that both ’RTAB-Map’ and ’Gmapping’ could produce accurate maps of a vineyard. Additionally, grid-based planners, such as Dijkstra and A*, performed better than a sample-based planner bias-IRRT*. Regarding obstacle avoidance, the SAA required a greater range of sensors to detect small and oddly shaped objects that could be found in a vineyard. The SAA maintained within 5mm of the specified distance when aiming to follow the row. The results from these experiments demonstrated the SAA’s ability to successfully transform a Yamaha golf cart into a semi-autonomous agricultural vehicle.

year: 2022

title: The Viscometric determination of somatic cell levels in cows' milk

authors: Milne, John Ross

abstract: The California Mastitis Test (CMT) is a test used for estimating the number of somatic cells in a milk sample. A reagent (secondary alkyl sulphate) is added to the milk and the number of somatic cells estimated from the resultant viscosity of the mixture. 
The Ruakura rolling ball viscometer has been developed to measure the viscosity of the CMT gel. It consists of a tube mounted horizontally so that the milk-reagent mixture can be introduced into it. After a holding time of 26 seconds the tube tips through an angle of 25° allowing a stainless steel ball to roll through the mixture for a standard time before returning to the horizontal. The distance the ball has rolled is inversely related to the viscosity developed. The physical function of the viscometer follows Stokes' Law. 
The range of the instrument is suited to reading the viscosity developed by the CMT reaction in New Zealand herd milks. 
The viscous reaction in milk is caused by somatic cell nuclei forming a fibrillar network. The reaction intensity is related to the DNA content of the milk sample. Proteins can modify the viscosity developed. Bacterial DNA does not enter the reaction. The network is fragile and rheomalaxic in nature. The reaction intensity in milk varies with time. An approximate 25 second holding time is required before determining the viscosity. After this holding time the reaction intensity progressively decreases. Milk to be tested should be under 24 hours old although refrigeration or boric acid preservative can extend this time. Different operators can rank milk samples by somatic cell count in a similar order with the Ruakura rolling ball viscometer. 
There is a significant correlation (r = 0.92***) between Ruakura rolling ball viscometer and somatic cell count of herd milk samples.

text: The Viscometric determination of somatic cell levels in cows' milk The California Mastitis Test (CMT) is a test used for estimating the number of somatic cells in a milk sample. A reagent (secondary alkyl sulphate) is added to the milk and the number of somatic cells estimated from the resultant viscosity of the mixture. 
The Ruakura rolling ball viscometer has been developed to measure the viscosity of the CMT gel. It consists of a tube mounted horizontally so that the milk-reagent mixture can be introduced into it. After a holding time of 26 seconds the tube tips through an angle of 25° allowing a stainless steel ball to roll through the mixture for a standard time before returning to the horizontal. The distance the ball has rolled is inversely related to the viscosity developed. The physical function of the viscometer follows Stokes' Law. 
The range of the instrument is suited to reading the viscosity developed by the CMT reaction in New Zealand herd milks. 
The viscous reaction in milk is caused by somatic cell nuclei forming a fibrillar network. The reaction intensity is related to the DNA content of the milk sample. Proteins can modify the viscosity developed. Bacterial DNA does not enter the reaction. The network is fragile and rheomalaxic in nature. The reaction intensity in milk varies with time. An approximate 25 second holding time is required before determining the viscosity. After this holding time the reaction intensity progressively decreases. Milk to be tested should be under 24 hours old although refrigeration or boric acid preservative can extend this time. Different operators can rank milk samples by somatic cell count in a similar order with the Ruakura rolling ball viscometer. 
There is a significant correlation (r = 0.92***) between Ruakura rolling ball viscometer and somatic cell count of herd milk samples.

year: 1973

title: Te whakahuatanga i te reo Māori: Kua ahatia e tātou i roto i ngā tau 100 kua hipa nei? (The pronunciation of Māori: What have we done to it in the last 100 Years?)

authors: Harlow, Ray

subjects: Te reo Māori

abstract: In the words of the proverb: 'The land remains, but humankind vanishes.' One should perhaps extend this to read: 'The land remains, humankind vanishes, and language changes.' For languages are old, handed down from one generation to another, but no matter what, they change. Present-day English is not Shakespeare's or Chaucer's language. The pronunciation has changed, new words have entered the language, some words have been lost, the grammar is now different. Māori is like that as well. Over the last two centuries, many aspects of the language have become different. Many words have been borrowed from English, and become part of the language. Many new words have been created in recent years to accommodate the new topics now being spoken about in Māori. Many words have changed their meaning, e.g., 'pūtea' originally a type of basket, but now a 'fund', source of money. In the grammar, there are now constructions being used which were not correct in earlier centuries.So far as the pronunciation is concerned, how is one to observe its development? That is the substance of a research project which has only just now begun, and it is the purpose of this paper to explain the nature of that research and show some of the preliminary findings. Hence the title: The pronunciation of Māori: What have we done to it in the last 100 years? The project is supported by the Marsden Research Fund.

text: Te whakahuatanga i te reo Māori: Kua ahatia e tātou i roto i ngā tau 100 kua hipa nei? (The pronunciation of Māori: What have we done to it in the last 100 Years?) In the words of the proverb: 'The land remains, but humankind vanishes.' One should perhaps extend this to read: 'The land remains, humankind vanishes, and language changes.' For languages are old, handed down from one generation to another, but no matter what, they change. Present-day English is not Shakespeare's or Chaucer's language. The pronunciation has changed, new words have entered the language, some words have been lost, the grammar is now different. Māori is like that as well. Over the last two centuries, many aspects of the language have become different. Many words have been borrowed from English, and become part of the language. Many new words have been created in recent years to accommodate the new topics now being spoken about in Māori. Many words have changed their meaning, e.g., 'pūtea' originally a type of basket, but now a 'fund', source of money. In the grammar, there are now constructions being used which were not correct in earlier centuries.So far as the pronunciation is concerned, how is one to observe its development? That is the substance of a research project which has only just now begun, and it is the purpose of this paper to explain the nature of that research and show some of the preliminary findings. Hence the title: The pronunciation of Māori: What have we done to it in the last 100 years? The project is supported by the Marsden Research Fund.

year: 2005-05