Large mobile irrigation machines are self-propelled sprinkler irrigation systems which farmers are rapidly adopting due to the high precision of the irrigation application. Although it is highly desirable that control systems be used with such machines to both optimise the irrigation water volume applied to field crops and optimise water use efficiency, there are difficulties in applying classical control techniques. These are caused principally by the very slow speed of crop growth-response and stress-response dynamics; but in addition characteristics of the plant and infield sensors which are poorly known and provide only sparse, low-quality data for feedback control. This paper outlines the operation of large mobile irrigation machines, analyses the limitations in the application of classical control approaches for their optimal use, and describes the methods that have been used to implement whole-system control via alternative (adaptive) approaches. These involve accommodation of sparse and unreliable input data and the application and evaluation of a range of irrigation volumes on different sub-areas of the field as on-the-go local system identification.
007This paper justifies the need for more research in the area of ‘assistive robotics’ and it describes the design and performance of a manipulator arm and gripper, mounted on an electric scooter, that can enable frail elderly and people with disabilities to collect and retrieve heavy objects, such as shopping items, located on high shelves. Known by the acronym “ESRA”, short for “Electric Scooter Robot Arm”, this device can be attached to a mobile vehicle such as an electric scooter or an electric-powered wheelchair. This paper discusses the basic mechanical design of the ESRA manipulator and gripper, joint control, overall performance, and important design tools that were used for its development. The object retrieval performance of this manipulator can also be enhanced using machine vision techniques for automatic object detection and gripper guidance. Different end-effector tools can be mounted on the end of the ESRA to enable the operator to perform a wide variety of common household chores and manipulation tasks.
008This paper discusses the benefits of using competitions in the teaching activities for a 1st or 2nd year mechatronic engineering subject that teaches microcontrollers and/or mobile robotics using a “hands on” PBL (Problem Based Learning) approach to learning and assessment. It describes, in detail, effective competition design philosophies and guidelines for creating different types of robotics competitions (and their rules) which help to keep most students highly motivated and engaged in their learning and self-education.
A "hands on" one-semester microcontroller programming subject is used to illustrate three different case studies (competitions) that were implemented which resulted in this particular subject achieving very high "satisfaction" marks in student surveys and attracting a great deal of praise from students. Student feedback and survey results are analysed briefly and compared to the subject’s learning objectives. The same teaching principles and similar kinds of technical competitions can also be used to achieve successful learning outcomes in other kinds of technical or engineering related subjects.
This paper also describes general principles for designing an effective "lab based" course structure and how technical concepts and materials can be presented, learned quickly, and assessed in order to produce very interested and highly motivated students who are keen to teach themselves practical real world skills with minimum stress and maximum enjoyment. The case studies include a robotic racing car competition, a multi-player box grabbing contest over a rocky obstacle course and a "robot wars / sumo” style competition that was televised nationwide in Australia.
Hearing implants are an important devices for combating deafness over the next 15 years. In this paper, we focus on the means to determine the sensitivity of the hearing organ to disturbances produced by implants and other interventions, and those induced by implantation. The preservation of residual hearing is an important aspect to be considered, however, the sensitivity of this to the process of implantation, device location and power levels is not well understood. Within this paper, a new experimental set-up to contrast the merits of different implantation techniques, implant location and power transmission are discussed and the initial results regarding disturbance levels using different surgical techniques are described.
018This paper presents investigations into the development of hybrid control schemes for input tracking and anti-swaying control of a rotary crane system. A lab-scaled rotary crane is considered and the dynamic model of the system is derived using Euler-Lagrange formulation. To study the effectiveness of the controllers, initially a collocated proportional-derivative (PD) control is developed for horizontal angle position control of rotary crane. This is then extended to incorporate input shaper control schemes for anti-swaying control of the system. The positive input shapers with the derivative effects are designed based on the properties of the system. Implementation results of the response of the rotary crane with the controllers are presented in time and frequency domains. The performances of hybrid control schemes are examined in terms of level of input tracking capability, swing angle reduction, and time response specifications in comparison to PD control. Finally a comparative assessment of the control techniques is discussed and presented.
021A method is investigated for damping the oscillation of a very wide agricultural spray rig. At present, mechanical dampers couple the rolling disturbance of the vehicle into the tilt of the spray booms and an alternative technique is desirable. A method whereby the booms are driven in a manner analogous to a tightrope walker's balancing pole is shown to be effective. However, modelling of further dynamics of the system shows that a solution is not simple.
029Scanning infra-red laser range finders and millimetre-wave radar
have
seen extensive application in automation and other mapping scenarios in
a wide range of research and commercial environments. There has,
however, been relatively limited use of these sensing technologies in
the mining industry.
This paper presents results obtained through the development of a
unique mining terrain mapping system which combines millimetre wave and
laser scanners to provide enhanced mining situational awareness
capability. This module forms part of an electric rope shovel
mining machine, a key component implementation of a larger automated
swing assist system.
A comparison of the use of laser and radar data for the purpose of creating Digital Terrain Maps (DTMs) and object pose estimation is given which includes, a comparative evaluation of terrain mapping data obtained from prototype millimeter-wave radar and several commercially available 2D scanning lasers mounted on large rotating excavation machinery. The registered laser data is compared with the results of a terrain model obtained through stereo vision, and, subsequently, with the radar data.
The situational awareness component of the control system uses information obtained by scanning infra-red laser range finders, a millimeter-wave radar unit and an inertially aided RTK GPS to create a digital terrain map of the environment. This map is utilised in path planning by a third party trajectory planning system and to provide the location and orientation of the waiting haul-truck to the shovel’s collision avoidance system.
The future automated system will allow the machine control system to autonomously perform swing-dump-return components of the shovel production cycle. The digging, crawler motion and overall operational planning will still be manually controlled by the operator at this stage and computer control can be seamlessly aborted by the operator at any stage.
033The Human-Computer Interaction (HCI) field has been around for almost 25 years. During that time, technological and socio-technical horizons have been transformed many times and computer systems have become an inseparable and natural part of our daily life: they monitor us, they guide us, and they help us to save time and money. Their presence is especially crucial in industrial applications as they facilitate improvements of production performance, enhancements in safety and automation of a wide range of industrial processes. In addition, immersive computer systems used in collaborative interactive environments with multiple participants have the potential for improving timely task completion. The present work adds an important layer to these often complex systems and considers distributed collaborative experiments for the mining industry as an immersive virtual reality (IVR) environment. The potential of IVR technology and HCI techniques as a major technical advance for supporting teleoperation has already been well recognized by various industries (Bowman et al. 2004, Sherman and Craig 2002). One of its unique advantages is the capability to allow operators to visualize abstract concepts, to “visit” remote environments and to interact with objects or events that distance, time, scale or safety factors make difficult or impossible. Teleoperation scenarios offer clear safety advantages compared to the physical presence of people in hazardous, harmful environments. The same techniques can also be used for e-education and fully interactive training purposes, where all possible scenarios can be presented through a virtual reality world.
Our investigation shows a generalized framework of utilizing modern technologies by bringing together HCI, IVR, computer vision (CV) and remote collaboration. A distributed (human-centered) collaborative immersive virtual reality framework (DCIVRF) is proposed in this work and several case studies are mentioned to validate the system and to answer the following questions:
• How to enhance an integrated environment for collaboration?
• How to evaluate human experience and human requirements during collaboration rather than technical evaluations only?
• How to share information effectively between people in a collaborative environment?
• How to use this modern technology effectively and which solutions are the most natural for collaborating with partners, depending on tested scenario?
• How to build intuitive user interfaces that optimize ease of use and minimize adoption/training time for new users?
• How to build the knowledge databases for future reference in collaborative scenarios?
The validation of DCIVRF consists of several distinct stages: idea generation, cost estimation, proof of concept, product development, testing against above-mentioned questions, data collection and generation of valuable outputs. To accommodate a collaborative working environment for team members working in distributed locations, the Virtual Mining Centre (VMC) at CSIRO's Queensland Centre for Advanced Technologies will provide a virtual design studio/virtual reality environment. The VMC comprises a 4-m dome screen, 3D spatial sound system, two High Definition (HD) projectors, Ultra5® data gloves, Inertial Measurement Unit (IMU) devices, Global Positioning System (GPS) devices, LadyBug3® 360º spherical digital video camera, Bumblebee2® stereo-camera and other equipment.
Our driving research hypothesis is that ICVE, being inherently spatial and immersive, will provide a better frame of reference for supporting teleoperation and collaboration activities than traditional CVE and video-based collaboration technology. It is hypothesized that geographically distributed operators engaged in ICVE will collaborate, operate robots, behave and feel more as though they were face-to-face and interacting on site with mining equipment. We apply the same reasoning to the use of ICVE for the virtual presentation of a mine engineering e-book.
034A finite element based approach to identify unknown mechanical properties of a biological soft tissue sample, using mechanical palpation load-displacement data, is presented. In-vivo tissue property identification is vitally important during surgical procedures, and surgeons use tactile sensing to identify malignant tissue. However, with robot assisted minimally invasive surgery (RMIS), tactile feedback is generally not available. To overcome this problem, researchers have proposed mechatronic probes mimicking some of the palpation capabilities of a human finger. This paper presents a non-linear finite element based approach for tissue property identification, during mechanical palpations by a mechatronic finger. A finite element model and the Newton-Raphson method is used to estimate soft tissue parameters. The approach is validated using a sphere-soft tissue indentation experiment on a silicone phantom. Test results show that the proposed method can identify soft tissue parameters accurately and robustly with a relatively fast convergence rate.
036
At present asphalt pavement defects are distinguished subjectively. The
recognition depends greatly on human vision, which can bring large
variations for micro-wave heating control. The paper adopts machine
vision aided locating to create accurate heating control data that is
objective and independent of human to overcome the deficiency. Firstly,
the micro-wave heating control system (MWHCS) based on machine vision
is presented. Then, the algorithms of cubic polynomial warping and
re-projection transformation are applied to rectify the image
distortion. Thirdly, the automatic and manual methods to create heating
control data are discussed. At last, an economical driving circuit
design matching with the heating data is demonstrated. Product testing
proves that the proposed heating control method with machine vision is
prompt and accurate in locating defects, also quite effective in energy
saving.
Key Words: asphalt pavement defects, machine vision aided locating,
distortion rectification.
For more than a decade the CSIRO Mine Automation Group has undertaken research into the application of advanced inertial navigation technologies and techniques for the guidance of underground mining equipment. Earlier results gained from pioneering demonstration projects (Reid 2001) led the Australian coal industry to fund a major longwall automation project through the Australian Coal Association Research Program (ACARP), with CSIRO as the primary research provider.
The eight year longwall automation project yielded novel inertial navigation solutions for the guidance of underground mining equipment which are now covered by international patents (Hainsworth 2000). In particular a Shearer Position Measurement System (SPMS) was developed to provide 3D measurement of a longwall shearing machine with centimetre accuracy. Importantly, the design of the system is such that it is not subject to the usual time dependent drifts associated with conventional inertial navigation systems (INS).
The longwall automation project also involved development of scanning laser techniques to improve navigation performance by independently measuring the closing distance (retreat) of the shearer and sideways lateral creep of the longwall mining system.
This paper describes the core technology outcomes of this research project referred to as LASC Technology which is now installed at multiple Australian longwall sites. LASC Technology is now being supplied by all the major longwall equipment manufactures under international licensing agreements with CSIRO.
039We describe research and development into an advanced suite of non-contact sensing methods to provide new automation capabilities for the Australian mining industry. The effort is being undertaken by CSIRO Automation, based at the Queensland Centre for Advanced Technologies (QCAT), Australia. The primary motivation is to provide robust localisation solutions in contexts where GPS is not available, such as the underground or other signal deprived environments.
Experiments are underway to compare the relative accuracy of several different localisation modalities utilising a remotely controlled mobility platform, called the Phoenix. A range of instruments have been mounted on the Phoenix: a transverse view stereo video camera, a ground sensing radar and a transverse mounted laser scanner. Ground truth is captured by a multi-beam laser scanner mounted on a stationary tripod, which independently tracks the path of the Phoenix during travel. When complete, the results of the research will be used to provide a robust system for teleoperation and automation of large-scale underground mining vehicles.
One of the main methods for localisation of mining machinery is by use of Inertial Navigation Systems (INS) (Reid et al. 2006). The accuracy of these sensors is greatly enhanced by the addition of an external aiding information source, such as velocity, for internal filter augmentation. Current applications typically use either Differential GPS or wheeled odometry as the velocity source (Farrell et al. 2000; Hideo et al. 2002). However, some recent research has explored monocular image tracking (George and Sukkarieh 2007) and visual angle tracking (Giebner 2003).
The INS accuracy improvement gained by the addition of a velocity motion sensing (VMS) aiding signal is directly related to the accuracy of the velocity signal.
Learning an optimal policy in a single-agent foraging task is important to balance the trade-off between exploration and exploitation issue in Q-learning. In this paper, a foraging task has been considered to study the influences of the available policies reported in the open literature. A mobile robot is modeled and used to search and retrieve pucks back to a home location within a time constraint. The performances of the policies will be assessed by evaluating the number of pucks and collisions the agent performs in the environment while following the respective policies. The agent’s main objective is to maximize the number of pucks collected and to minimize the number of collisions in the environment. The results of the experiments conducted with the various policies are presented and discussed clearly in this paper.