Investigation on Mlp Artificial Neural Network Using FPGA For Autonomous Cart Follower System

Dengan kos alat pengesan yang semakin rendah, masa depan sistem pedati pengikut autonomi akan dilengkapi dengan lebih banyak alat pengesan. Ini menjadi cabaran rekabentuk dalam mengendalikan data besar dan kerumitan perkukuhan. Kebanyakan sistem yang sedia ada menggunakan papan mikropengawal yang mempunyai prestasi yang terhad dan pengembangan tidak mungkin tanpa penggantian yang lebih baru. Projek ini mencadangkan perlaksanaan alternatif sistem pedati pengikut autonomi dengan model rangkaian neural MLP menggunakan FPGA. Sistem pedati pengikut autonomi yang mengguakan papan mikropengawal telah diubah suai untuk menggunakan papan FPGA dan dilaksanakan melalui Sistem pada Chip (SOC). System rangkaian neural dilatih dalam simulasi dengan vektor latihan yang dikumpul daripada sistem pedati pengikut autonomi yang sedia ada. System rangkaian neural kemudian dilaksanakan sebagai perkukuhan dalam SOC itu. Dalam pemerhatian, jejak perkukuhan model rangkaian neural kekal saiz kecil tanpa mengira saiz rangkaian neural. Hasil kajian menunjukkan bahawa dengan penggunaan sumber tambahan sebanyak 40%, penambahbaikan sistem secara keseluruhan sebanyak 27 kali dicapai dengan penggunaan blok pecutan perkakasan di SOC, berbanding dengan SOC tanpa penggunaan blok pecutan perkakasan. ________________________________________________________________________________________________________________________ The future of the autonomous cart follower system will equipped with lots of sensory data, due to the ever lower cost of sensory device. This provides design challenge on handling large data and firmware complexity. Most of the existing systems are implemented via usage of microcontroller board, which has limited performance and expansion is not possible without replacement of newer board. The project proposes an alternative approach of running the autonomous cart follower systems on neural network model using Field Programmable Gates Array (FPGA). A microcontroller based autonomous cart follower systems is modified to use the FPGA board and implemented via the System on Chip (SOC) approach. The neural network is trained offline in simulation tools with training vector collected from running the existing autonomous cart follower systems. The trained neural network model then implemented as software code in the SOC. By observation the firmware footprint of the neural network model remains small size regardless of the neural network size. The result shows that with 40% more additional resource utilization, the overall system improvement of 27 times is achieved with the usage of hardware acceleration block in SOC compared to SOC without hardware acceleration

Visual Based Cart Follower Using Artificial Neural Network

A visual based cart follower can benefit as a helper robot. It can track and follow a wheelchair user without having any physical attachment between them. In addition, the low intensity of the surrounding light can affect the tracking performance too. In this study, the cart follower that equipped with all tracking component has been developed. The system was also integrated with Artificial Neural Network (ANN) for good visual navigation. A colour tracking method being used for following task application with Pixy CMUcam5 camera. It gathered the information of the width, height, area, angle, x and y coordination of the colour pattern board which situated behind the wheelchair and translate this information into relative position information which enable the cart to follow the wheelchair. The activation function being used is saturating linear (satlin). The Field of View (FOV) of Pixy CMUcam5 is from 69.98o to 76.83o with vertical distance of 20cm to 150cm. The optimum target colour size for maximum distance 150cm is 98.07cm2. The distance from the top view shows that the minimum and maximum distance error is 0.40cm and 2.30cm while the maximum and minimum angle error is 5.30o and 21.30o from point P0 to P1, P2 and P3 respectively. The most ideal tracking condition is at 205 Lux since the error rate for each R, G and B value is the lowest. The final error simulation test shows that there is 0.65% and 4.27% of error in minimum distance 20cm and -15o angle while 1.93% and 5.57% of error in maximum distance 69cm and 30o angle. The overall test performance shows that the error occurred in distance is 1.62% meanwhile 5.39% in angle. As a conclusion, the tracking system for cart follower has been developed and integration of ANN has achieved its deserved accuracy with the final error test

CONCEPTUAL DESIGN OF AUTONOMOUS CART FOLLOWER FOR WHEELCHAIR USER

This paper focuses on kinematics of the cart follower and the system identification of propulsion system by using brushed DC motor. The cart follower uses Ackermann configuration as the steering system. The modeling of kinematics equation takes into account the instantaneous center of rotation (ICR), velocity of each tire, heading angle, and simple movement of the cart. The cart is propelled by transaxle brushed DC motor. It is important to approximate an accurate transfer function to represent the motor as the plant module is unavailable. The motor is simulated by using Arduino hardware package in MATLAB®. Rotary encoder is used to record the angular velocity of the shaft. MATLAB® code is created in order to calculate the linear velocity and tabulate the datasets. System Identification Toolbox determines the transfer function of the motor and its performance. The variables measured in experiment to identify the transfer function of the DC motor system are output angular velocity and input voltage. The parameters taken from the DC motor’s mathematical model are derived based on existing literatures. The graph of output velocity against time is plotted and the transfer function is estimated by using System Identification Toolbox in MATLAB®. From the results, it is demonstrated that the motor exhibits second order system

Mobile Robots Navigation

Mobile robots navigation includes different interrelated activities: (i) perception, as obtaining and interpreting sensory information; (ii) exploration, as the strategy that guides the robot to select the next direction to go; (iii) mapping, involving the construction of a spatial representation by using the sensory information perceived; (iv) localization, as the strategy to estimate the robot position within the spatial map; (v) path planning, as the strategy to find a path towards a goal location being optimal or not; and (vi) path execution, where motor actions are determined and adapted to environmental changes. The book addresses those activities by integrating results from the research work of several authors all over the world. Research cases are documented in 32 chapters organized within 7 categories next described

Lab experiences for teaching undergraduate dynamics

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2003.Includes bibliographical references (p. 443-466).This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.This thesis describes several projects developed to teach undergraduate dynamics and controls. The materials were developed primarily for the class 2.003 Modeling Dynamics and Control I. These include (1) a set of ActivLab modular experiments that illustrate the dynamics of linear time-invariant (LTI) systems and (2) a two wheeled mobile inverted pendulum. The ActivLab equipment has been designed as shareware, and plans for it are available on the web. The inverted pendulum robot developed here is largely inspired by the iBOT and Segway transportation devices invented by Dean Kamen.by Katherine A. Lilienkamp.S.M

Enhancing tele-operation - Investigating the effect of sensory feedback on performance

The decline in the number of healthcare service providers in comparison to the growing numbers of service users prompts the development of technologies to improve the efficiency of healthcare services. One such technology which could offer support are assistive robots, remotely tele-operated to provide assistive care and support for older adults with assistive care needs and people living with disabilities. Tele-operation makes it possible to provide human-in-the-loop robotic assistance while also addressing safety concerns in the use of autonomous robots around humans. Unlike many other applications of robot tele-operation, safety is particularly significant as the tele-operated assistive robots will be used in close proximity to vulnerable human users. It is therefore important to provide as much information about the robot (and the robot workspace) as possible to the tele-operators to ensure safety, as well as efficiency. Since robot tele-operation is relatively unexplored in the context of assisted living, this thesis explores different feedback modalities that may be employed to communicate sensor information to tele-operators. The thesis presents research as it transitioned from identifying and evaluating additional feedback modalities that may be used to supplement video feedback, to exploring different strategies for communicating the different feedback modalities. Due to the fact that some of the sensors and feedback needed are not readily available, different design iterations were carried out to develop the necessary hardware and software for the studies carried out. The first human study was carried out to investigate the effect of feedback on tele-operator performance. Performance was measured in terms of task completion time, ease of use of the system, number of robot joint movements, and success or failure of the task. The effect of verbal feedback between the tele-operator and service users was also investigated. Feedback modalities have differing effects on performance metrics and as a result, the choice of optimal feedback may vary from task to task. Results show that participants preferred scenarios with verbal feedback relative to scenarios without verbal feedback, which also reflects in their performance. Gaze metrics from the study also showed that it may be possible to understand how tele-operators interact with the system based on their areas of interest as they carry out tasks. This findings suggest that such studies can be used to improve the design of tele-operation systems.The need for social interaction between the tele-operator and service user suggests that visual and auditory feedback modalities will be engaged as tasks are carried out. This further reduces the number of available sensory modalities through which information can be communicated to tele-operators. A wrist-worn Wi-Fi enabled haptic feedback device was therefore developed and a study was carried out to investigate haptic sensitivities across the wrist. Results suggest that different locations on the wrist have varying sensitivities to haptic stimulation with and without video distraction, duration of haptic stimulation, and varying amplitudes of stimulation. This suggests that dynamic control of haptic feedback can be used to improve haptic perception across the wrist, and it may also be possible to display more than one type of sensor data to tele-operators during a task. The final study carried out was designed to investigate if participants can differentiate between different types of sensor data conveyed through different locations on the wrist via haptic feedback. The effect of increased number of attempts on performance was also investigated. Total task completion time decreased with task repetition. Participants with prior gaming and robot experience had a more significant reduction in total task completion time when compared to participants without prior gaming and robot experience. Reduction in task completion time was noticed for all stages of the task but participants with additional feedback had higher task completion time than participants without supplementary feedback. Reduction in task completion time varied for different stages of the task. Even though gripper trajectory reduced with task repetition, participants with supplementary feedback had longer gripper trajectories than participants without supplementary feedback, while participants with prior gaming experience had shorter gripper trajectories than participants without prior gaming experience. Perceived workload was also found to reduce with task repetition but perceived workload was higher for participants with feedback reported higher perceived workload than participants without feedback. However participants without feedback reported higher frustration than participants without feedback.Results show that the effect of feedback may not be significant where participants can get necessary information from video feedback. However, participants were fully dependent on feedback when video feedback could not provide requisite information needed.The findings presented in this thesis have potential applications in healthcare, and other applications of robot tele-operation and feedback. Findings can be used to improve feedback designs for tele-operation systems to ensure safe and efficient tele-operation. The thesis also provides ways visual feedback can be used with other feedback modalities. The haptic feedback designed in this research may also be used to provide situational awareness for the visually impaired

Importance of embodiment towards co-operation in multi robot systems

The work presented in this thesis relates to one of the major ongoing problems in robotics: Developing control architectures for cooperation in Multi Robot Systems (MRS). It has been widely accepted that Embodiment is a prime requirement for Robotics. However, in the case of MRS research, two major shortfalls were identified. First, it was highlighted that no effort had been made into research platforms for Embodied MRS. Second, it was also observed that, generally, the more units in an MRS the lower their capabilities and as a result the poorer their degree of embodiment. These two issues were addressed separately. Firstly, a novel concept for MRS development platform named 'Re-embodiment' is presented. Re-embodiment aims to facilitate research on control systems for MRS by minimising the effort required to ensure that the robots remain embodied and situated. Using Re-embodiment, researchers can implement and test largely different control algorithms at virtually the same time on large fleets of robots. Secondly, an innovative mono vision distance measurement algorithm is presented. The intention is to provide a cheap, yet information rich, sensory input that can be realistically implemented on large fleet of robots. After a 'one off calibration of the image sensor, distances from the robot to objects in its environment can be estimated from single frames.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

2016 - The Twenty-first Annual Symposium of Student Scholars

The full program book from the Twenty-first Annual Symposium of Student Scholars, held on April 21, 2016. Includes abstracts from the presentations and posters.https://digitalcommons.kennesaw.edu/sssprograms/1015/thumbnail.jp

Importance of embodiment towards co-operation in multi robot systems

The work presented in this thesis relates to one of the major ongoing problems in robotics: Developing control architectures for cooperation in Multi Robot Systems (MRS). It has been widely accepted that Embodiment is a prime requirement for Robotics. However, in the case of MRS research, two major shortfalls were identified. First, it was highlighted that no effort had been made into research platforms for Embodied MRS. Second, it was also observed that, generally, the more units in an MRS the lower their capabilities and as a result the poorer their degree of embodiment. These two issues were addressed separately. Firstly, a novel concept for MRS development platform named 'Re-embodiment' is presented. Re-embodiment aims to facilitate research on control systems for MRS by minimising the effort required to ensure that the robots remain embodied and situated. Using Re-embodiment, researchers can implement and test largely different control algorithms at virtually the same time on large fleets of robots. Secondly, an innovative mono vision distance measurement algorithm is presented. The intention is to provide a cheap, yet information rich, sensory input that can be realistically implemented on large fleet of robots. After a 'one off calibration of the image sensor, distances from the robot to objects in its environment can be estimated from single frames

Medical Robotics

The first generation of surgical robots are already being installed in a number of operating rooms around the world. Robotics is being introduced to medicine because it allows for unprecedented control and precision of surgical instruments in minimally invasive procedures. So far, robots have been used to position an endoscope, perform gallbladder surgery and correct gastroesophogeal reflux and heartburn. The ultimate goal of the robotic surgery field is to design a robot that can be used to perform closed-chest, beating-heart surgery. The use of robotics in surgery will expand over the next decades without any doubt. Minimally Invasive Surgery (MIS) is a revolutionary approach in surgery. In MIS, the operation is performed with instruments and viewing equipment inserted into the body through small incisions created by the surgeon, in contrast to open surgery with large incisions. This minimizes surgical trauma and damage to healthy tissue, resulting in shorter patient recovery time. The aim of this book is to provide an overview of the state-of-art, to present new ideas, original results and practical experiences in this expanding area. Nevertheless, many chapters in the book concern advanced research on this growing area. The book provides critical analysis of clinical trials, assessment of the benefits and risks of the application of these technologies. This book is certainly a small sample of the research activity on Medical Robotics going on around the globe as you read it, but it surely covers a good deal of what has been done in the field recently, and as such it works as a valuable source for researchers interested in the involved subjects, whether they are currently “medical roboticists” or not