Mobile Robot Navigation for Person Following in Indoor Environments

Service robotics is a rapidly growing area of interest in robotics research. Service robots inhabit human-populated environments and carry out specific tasks. The goal of this dissertation is to develop a service robot capable of following a human leader around populated indoor environments. A classification system for person followers is proposed such that it clearly defines the expected interaction between the leader and the robotic follower. In populated environments, the robot needs to be able to detect and identify its leader and track the leader through occlusions, a common characteristic of populated spaces. An appearance-based person descriptor, which augments the Kinect skeletal tracker, is developed and its performance in detecting and overcoming short and long-term leader occlusions is demonstrated. While following its leader, the robot has to ensure that it does not collide with stationary and moving obstacles, including other humans, in the environment. This requirement necessitates the use of a systematic navigation algorithm. A modified version of navigation function path planning, called the predictive fields path planner, is developed. This path planner models the motion of obstacles, uses a simplified representation of practical workspaces, and generates bounded, stable control inputs which guide the robot to its desired position without collisions with obstacles. The predictive fields path planner is experimentally verified on a non-person follower system and then integrated into the robot navigation module of the person follower system. To navigate the robot, it is necessary to localize it within its environment. A mapping approach based on depth data from the Kinect RGB-D sensor is used in generating a local map of the environment. The map is generated by combining inter-frame rotation and translation estimates based on scan generation and dead reckoning respectively. Thus, a complete mobile robot navigation system for person following in indoor environments is presented

Toward Design of a Drip-Stand Patient Follower Robot

A person following robot is an application of service robotics that primarily focuses on human-robot interaction, for example, in security and health care. This paper explores some of the design and development challenges of a patient follower robot. Our motivation stemmed from common mobility challenges associated with patients holding on and pulling the medical drip stand. Unlike other designs for person following robots, the proposed design objectives need to preserve as much as patient privacy and operational challenges in the hospital environment. We placed a single camera closer to the ground, which can result in a narrower field of view to preserve patient privacy. Through a unique design of artificial markers placed on various hospital clothing, we have shown how the visual tracking algorithm can determine the spatial location of the patient with respect to the robot. The robot control algorithm is implemented in three parts: (a) patient detection; (b) distance estimation; and (c) trajectory controller. For patient detection, the proposed algorithm utilizes two complementary tools for target detection, namely, template matching and colour histogram comparison. We applied a pinhole camera model for the estimation of distance from the robot to the patient. We proposed a novel movement trajectory planner to maintain the dynamic tipping stability of the robot by adjusting the peak acceleration. The paper further demonstrates the practicality of the proposed design through several experimental case studies

Computer modelling and experimental design of a gait orthosis for early rehabilitation of walking

Walking is a fundamental human activity [1]. Rehabilitation of walking is one of the essential goals for patients with spinal cord injury (SCI) or other neurological impairments [2, 3]. Early rehabilitation is desirable to maximise the beneficial effects, so training programmes should be initiated even when patients are still on bed rest. In order to promote early rehabilitation of patients with incomplete spinal cord injury who cannot maintain an upright posture, a Gait Orthosis for Early Rehabilitation (GOER) of walking was designed [2] and evaluated in this PhD work. This research started with a gait analysis experiment, through which the kinematics and kinetics of overground walking were investigated. Based on experimental walking data from able-bodied subjects, a least squares algorithm was developed to approximate the foot trajectories with circles. The determination of the best-fit circle for the toe trajectory over the whole gait cycle provided the basis for inducing toe movement by a rigid bar. Therefore a model of a two-bar mechanism was developed in Matlab/SimMechanics to simulate supine stepping. The simulated kinematics, including the angles of the hip, knee and ankle joints, showed comparable ranges of motion (ROMs) to the experimental walking performance in able-bodied subjects. This two-bar model provided the basis for the development of the GOER system. The intersegmental kinetics of the lower limb motion during supine stepping were investigated through computer simulation. A model of a leg linkage was firstly developed to simulate upright walking. After the model was validated by successful simulation of dynamic performance similar to experimental overground walking, the model was rotated by 90o to simulate stepping movement in a supine posture. It was found that the dynamics of the hip joint were significantly influenced by the position change from upright to supine, which highlighted the importance of a leg-weight support during supine stepping. In contrast, the kinetics of the ankle joint were much influenced by the forces applied on the foot sole which mimicked the ground reaction occurring during overground walking. Therefore a suitable force pattern was required on the foot sole in order to train the ankle joint during supine stepping. The simulated kinematic and kinetic results provided the basis for the design process of the GOER system. A GOER prototype with mechanisms for one leg was manufactured, which included a bar linkage to move the leg frame upwards and downwards and a cam-roller mechanism to rotate the shoe platform. The bar-cam GOER prototype achieved coordinated movements in the leg frame through constant rotation of an electric motor. Preliminary tests were carried out in three able-bodied subjects who followed the movements produced by the GOER prototype. The subjects felt walking-like stepping movement in the lower limb. Synchronised motion in the hip, knee and ankle joints was obtained, with the ROMs in the physiological ranges of motion during overground walking. The experimentally obtained joint profiles during supine stepping matched the simulated supine stepping and were close to the profiles during overground walking. Apart from inducing proprioceptive feedback from the lower limb joints, the GOER system required dynamic stimulation from the shoe platform to mimic load occurring during the stance phase of overground walking. Activated by pneumatic components, the shoe platform managed to apply forces on the foot sole with adjustable amplitudes. The pneumatic shoe platform was evaluated in ten able-bodied subjects and managed to induce walking-like pressure sensation on the foot sole with physiological responses from the leg muscles. In summary, this thesis developed and evaluated a new gait training robotic system targeting supine stepping for patients who are still restricted to a lying position. The conceptual design process was developed through computer modelling and it was implemented as a prototype. Evaluation tests on able-bodied subjects proved the technical feasibility of the robotic system for supine stepping and led to recommendations for further development

Design and Evaluation of Pediatric Gait Rehabilitation Robots

Gait therapy methodologies were studied and analyzed for their potential for pediatric patients. Using data from heel, metatarsal, and toe trajectories, a nominal gait trajectory was determined using Fourier transforms for each foot point. These average trajectories were used as a basis of evaluating each gait therapy mechanism. An existing gait therapy device (called ICARE) previously designed by researchers, including engineers at the University of Nebraska-Lincoln, was redesigned to accommodate pediatric patients. Unlike many existing designs, the pediatric ICARE did not over- or under-constrain the patient’s leg, allowing for repeated, comfortable, easily-adjusted gait motions. This design was assessed under clinical testing and deemed to be acceptable. A gait rehabilitation device was designed to interface with both pediatric and adult patients and more closely replicate the gait-like metatarsal trajectory compared to an elliptical machine. To accomplish this task, the nominal gait path was adjusted to accommodate for rotation about the toe, which generated a new trajectory that was tangent to itself at the midpoint of the stride. Using knowledge of the bio-mechanics of the foot, the gait path was analyzed for its applicability to the general population. Several trajectory-replication methods were evaluated, and the crank-slider mechanism was chosen for its superior performance and ability to mimic the gait path adequately. Adjustments were made to the gait path to further optimize its realization through the crank-slider mechanism. Two prototypes were constructed according to the slider-crank mechanism to replicate the gait path identified. The first prototype, while more accurately tracing the gait path, showed difficulty in power transmission and excessive cam forces. This prototype was ultimately rejected. The second prototype was significantly more robust. However, it lacked several key aspects of the original design that were important to matching the design goals. Ultimately, the second prototype was recommended for further work in gait-replication research. Advisor: Carl A. Nelso

Smart Sensors for Healthcare and Medical Applications

This book focuses on new sensing technologies, measurement techniques, and their applications in medicine and healthcare. Specifically, the book briefly describes the potential of smart sensors in the aforementioned applications, collecting 24 articles selected and published in the Special Issue “Smart Sensors for Healthcare and Medical Applications”. We proposed this topic, being aware of the pivotal role that smart sensors can play in the improvement of healthcare services in both acute and chronic conditions as well as in prevention for a healthy life and active aging. The articles selected in this book cover a variety of topics related to the design, validation, and application of smart sensors to healthcare

Towards a Legal end Ethical Framework for Personal Care Robots. Analysis of Person Carrier, Physical Assistant and Mobile Servant Robots.

Technology is rapidly developing, and regulators and robot creators inevitably have to come to terms with new and unexpected scenarios. A thorough analysis of this new and continuosuly evolving reality could be useful to better understand the current situation and pave the way to the future creation of a legal and ethical framework. This is clearly a wide and complex goal, considering the variety of new technologies available today and those under development. Therefore, this thesis focuses on the evaluation of the impacts of personal care robots. In particular, it analyzes how roboticists adjust their creations to the existing regulatory framework for legal compliance purposes. By carrying out an impact assessment analysis, existing regulatory gaps and lack of regulatory clarity can be highlighted. These gaps should of course be considered further on by lawmakers for a future legal framework for personal care robot. This assessment should be made first against regulations. If the creators of the robot do not encounter any limitations, they can then proceed with its development. On the contrary, if there are some limitations, robot creators will either (1) adjust the robot to comply with the existing regulatory framework; (2) start a negotiation with the regulators to change the law; or (3) carry out the original plan and risk to be non-compliant. The regulator can discuss existing (or lacking) regulations with robot developers and give a legal response accordingly. In an ideal world, robots are clear of impacts and therefore threats can be responded in terms of prevention and opportunities in form of facilitation. In reality, the impacts of robots are often uncertain and less clear, especially when they are inserted in care applications. Therefore, regulators will have to address uncertain risks, ambiguous impacts and yet unkown effects

Proceedings of the Scientific-Practical Conference "Research and Development - 2016"

talent management; sensor arrays; automatic speech recognition; dry separation technology; oil production; oil waste; laser technolog

Wings in Orbit: Scientific and Engineering Legacies of the Space Shuttle, 1971-2010

The Space Shuttle is an engineering marvel perhaps only exceeded by the station itself. The shuttle was based on the technology of the 1960s and early 1970s. It had to overcome significant challenges to make it reusable. Perhaps the greatest challenges were the main engines and the Thermal Protection System. The program has seen terrible tragedy in its 3 decades of operation, yet it has also seen marvelous success. One of the most notable successes is the Hubble Space Telescope, a program that would have been a failure without the shuttle's capability to rendezvous, capture, repair, as well as upgrade. Now Hubble is a shining example of success admired by people around the world. As the program comes to a close, it is important to capture the legacy of the shuttle for future generations. That is what "Wings In Orbit" does for space fans, students, engineers, and scientists. This book, written by the men and women who made the program possible, will serve as an excellent reference for building future space vehicles. We are proud to have played a small part in making it happen. Our journey to document the scientific and engineering accomplishments of this magnificent winged vehicle began with an audacious proposal: to capture the passion of those who devoted their energies to its success while answering the question "What are the most significant accomplishments?" of the longestoperating human spaceflight program in our nation s history. This is intended to be an honest, accurate, and easily understandable account of the research and innovation accomplished during the era