Browsing by Author "Muthugala, MAVJ"

Now showing 1 - 11 of 11

item: Article-Full-text
Adapting approaching proxemics of a service robot based on physical user behavior and user feedback
(Springer Netherlands, 2022) Samarakoon, SMBP; Muthugala, MAVJ; Jayasekara, AGBP; Elara, MR
Service robots with social interactive features are developed to cater to the demand in various application domains. These robots often need to approach toward users to accomplish typical day-to-day services. Thereby, the approaching behavior of a service robot is a crucial factor in developing social interactivity between users and the robot. In this regard, a robot should be capable of maintaining proper proxemics at the termination position of an approach that improves the comfort of users. Proxemics preferences of humans depend on physical user behavior as well as personal factors. Therefore, this paper proposes a novel method to adapt the termination position of an approach based on physical user behavior and user feedback. Physical behavior of a user is perceived by the robot through analyzing skeletal joint movements of the user. These parameters are taken as inputs for a fuzzy neural network that determines the appropriate interpersonal distance. The preference of a user is learnt by modifying the internal parameters of the fuzzy neural network based on user feedback. A user study has been conducted to compare and contrast behavior of the proposed system over the existing approaches. The outcomes of the user study confirm a significant improvement in user satisfaction due to the adaptation toward users based on feedback.
item: Conference-Full-text
Application of robot autobiographical memory in long-term human-robot social interactions
(Institute of Electrical and Electronics Engineers, Inc., 2018-09) Edirisinghe, MMSN; Muthugala, MAVJ; Jayasekara, AGBP; Samarasinghe, R; Abeygunawardana, S
Robots are becoming a part of the human society. They are intended to maintain long-term social interactions with humans. A memory about each interaction partner is essential for a robot for maintaining long-term social interactions. Therefore, robot memory must possess the abilities for extracting, storing, updating and recalling information during social interactions. This work studies the application of a robot’s autobiographical memory in long-term social interactions in multi-user environments. The proposed system is capable of acquiring knowledge about users through friendly conversations and recall them during future interactions. The autobiographical memory which has been designed with a three-layered architecture is employed for storing significant information which is required for long-term social interactions. The interaction manager module has been designed as a finite state machine for managing the interaction between the robot and the user. Dialogue flows were defined for each state to communicate with the user. The system has been tested and validated by using a set of experiments.
item: Conference-Full-text
Design and development of a smart wheelchair with multiple control interfaces
(IEEE, 2018-05) Yashoda, HGMT; Piumal, AMS; Polgahapitiya, PGSP; Mubeen, MMM; Muthugala, MAVJ; Jayasekara, AGBP; Chathuranga, D
The degradation of mobility is one of the major concerns that affect the independent living ability of elderly/ disabled people. Therefore, mobility assistive devices are being developed to uplift the living standards of the people. However, the existing mobility assistive devices require improvements. This paper presents about design and development of a smart wheelchair with multiple control interfaces. A prototype of the smart wheelchair system has been developed based on a conventional wheelchair that is commonly available in the market, with the addition of related electrical and mechanical advancements. Voice and gesture controlling interfaces are deployed to the system in addition to the conventional joystick-controlling interface to enhance the interaction with the user. Particulars on the mechanical design, the electrical and control system of the smart wheelchair are presented. Experiments have been conducted to verify the functionality of the developed smart wheelchair. Furthermore, the user preferences between the different controlling interfaces have been evaluated through a user study and the results are presented.
item: Conference-Full-text
Design and development of an anthropomorphic robotic head with force attentive reflex actions
(IEEE, 2016-05) Jayasekara, AGN; Muthugala, MAVJ; Jayasekara, AGBP; Jayasekara, AGBP; Bandara, HMND; Amarasinghe, YWR
Anthropomorphism is the attribution of human traits, emotions and intentions to non-human entities. Nowadays, development of anthropomorphic features in robotic heads is a major area of interest in the field of robotics. Many robotics heads with anthropomorphic features are developed to improve the social interaction between robots and humans. However, the existing robotic heads need improvements in construction and behaviors to facilitate more friendly interactions. This paper presents about design and development of an anthropomorphic robotic head that can make reflex actions based on external forces applied on it. The design parameters of the robotic head have been decided by examining the biomechanics of human head. The robotic head has been designed with 3 DoFs for the neck section. The developed force attentive mechanism is capable of identifying the direction of the applied force. The response of the robot depends on the direction of the external force and the response is decided by a reaction function. Functionalities of the robotic head have been verified from the experimental results and the results are presented. Furthermore, the robotic head has been designed and developed in such a way that it can be used as a research platform for future research.
item: Thesis-Full-text
Enhancing interpretation of uncertain information in Navigational commands for service robots using neuro-fuzzy approach
Muthugala, MAVJ; jayasekara, B
An intelligent service robot is a machine that is able to gather information from the environment and use its knowledge to operate safely in a meaningful and purposive manner. Intelligent service robots are currently being developed to cater to demands in emerging areas of robotic applications such as caretaking and assistance, healthcare and edutainment. These service robots are intended to be operated by nonexpert users. Hence, they should have the ability to interact with humans in a human-friendly manner. Humans prefer to use voice instructions, responses, and suggestions in their daily interactions. Such voice instructions and responses often include uncertain information such as “little” and “far” rather than precise quantitative values. The uncertain information such as “little” and “far” have no deﬁnitive meanings and depend heavily on factors such as environment, context, user and experience. Therefore, the ability of robots to understand uncertain information is a crucial factor in the implementation of human-friendly interactive features in robots. This research has been conducted with the intention of developing eﬀective methodologies for interpreting uncertain notions such as “little”, “near” and “far” in navigational user commands in order to enhance human-robot interaction. The natural tendencies of humans have been considered for the development of the methodologies since ability of the robot in replicating the natural behavior of humans vastly enhances the rapport between the robot and the user. The methodologies have been developed using fuzzy logic and fuzzy neural networks that are capable of adapting the perception of uncertain information according to the environment, experience and user. User studies have been conducted in artiﬁcially created domestic environments to experimentally validate the performance of the proposed methods. An intelligent service robot named as Moratuwa Intelligent Robot (MIRob), which has been developed as a part of the research, has been used for the experiments. The robot’s perception of distance and direction related uncertain information in navigation commands is adapted according to the environment. According to the experimental results, a service robot can eﬀectively cope with distance-related uncertain information when the robot’s perception of distance-related uncertain information is adapted to the environment. The eﬀectiveness can be further improved by perceiving the environment in a human-like manner. The adaptation of the directional perception in accordance to the environment remarkably improves the overall interpretation ability of uncertain notions. User feedback is used to adapt the perception toward the user while adapting to the environment and this adaptation vastly improves user satisfaction. Methods have also been proposed to interpret the uncertain information in relation to relative references and the methods are capable of replicating human-like behavior. Furthermore, the information conveyed though pointing gestures that accompany voice instructions is fused to further enhance the understanding of the user instructions. This fusion signiﬁcantly reduces the errors in interpreting the uncertain information. Furthermore, it reduces the number of steps required to navigate a robot toward a goal. A vast research gap is still remaining in this particular research niche for future developments and hence possible future improvements are also synthesized.
item: Article-Full-text
Enhancing User Satisfaction by Adapting Robot's Perception of Uncertain Information Based on Environment and User Feedback
(IEEE, 2017) Muthugala, MAVJ; Jayasekara, AGBP
Assistive robots have been developed to improve the living standards of older people. These assistive robots are intended to be operated by non-expert users. Hence, they should have the ability to interact with humans in a human-friendly manner. Humans prefer to use voice instructions, responses, and suggestions in their daily interactions. Such voice instructions and responses often include uncertain terms and lexical symbols rather than precise quantitative values. Therefore, the ability of robots to understand uncertain information is a crucial factor in the implementation of human-friendly interactive features in robots. This paper proposes a novel method of adapting the perception of the uncertain spatial information contents of navigational commands, such as ``far'' and ``little'', based on environmental factors and user feedback. The proposed uncertain information understanding module has been implemented using fuzzy neural networks in such a way that the system can concurrently adapt to environmental factors while learning from user feedback. The proposed method has been implemented on the MIRob platform, and experiments have been conducted in an arti cially created domestic environment to evaluate the performance and behaviors of the proposed concept. The experimental results validate the improvement of user satisfaction related to the understanding of uncertain information.
item: Conference-Full-text
Intelligent robot companion capable of controlling environment ambiance of smart houses by observing user's behavior
(Institute of Electrical and Electronics Engineers, Inc., 2018-09) Senarathna, SMSS; Muthugala, MAVJ; Jayasekara, AGBP; Samarasinghe, R; Abeygunawardana, S
Robot companions are being developed to assist humans in domestic environments. This paper proposes an intelligent robot companion which is capable of adapting the ambient conditions of a smart home environment in accordance to the user behavior. The user behavior identification is facilitated by an artificial neural network that has been trained to detect the different postures of humans such as sitting and standing. Based on the identified user behavior, the robot controls smart devices available in the home to realize the adaptation of ambient conditions. The smart devices and the companion robot connect over a wireless network. Furthermore, voice interaction capabilities have also been incorporated to the robot companion to facilitate voice interaction based controlling of ambient conditions. A prototype of the system has been developed and the capabilities of the system have been validated experimentally.
item: Conference-Full-text
Interpreting Fuzzy Linguistic Information in User Commands by Analyzing Movement Restrictions in the Surrounding Environment
(2015-08-03) Muthugala, MAVJ; Buddhika, AG; Jayasekara, P
Assistive robots for elderly and disabled people are being developed to uplift the living standard of the people. The idea of realizing the dream for a robot assistant obviously depends on the availability of human-human like interactions in human-robot interactions also. Humans prefer to use voice instructions, which have uncertain information such as “very little”, “far” etc. in their daily interactions. Therefore, the ability of a robot assistant to understand the uncertain information is crucial. Therefore, our study proposes a method to interpret fuzzy linguistic information related to distance in user commands by evaluating the spatial information of the surrounding environment. Fuzzy logic based fuzzy linguistic information evaluation system (FLIES) has been introduced to interpret the fuzzy linguistic terms in user commands by analyzing possible movement restrictions in the surrounding environment. The proposed method has been implemented and tested on a Pioneer 3DX mobile robot. The experiment has been conducted in two different indoor environments and the experimental results of the system are presented.
item: Conference-Full-text
Mirob: an intelligent service robot that learns from interactive discussions while handling uncertain information in user instructions
(IEEE, 2016-04) Muthugala, MAVJ; Jayasekara, AGBP; Jayasekara, AGBP; Bandara, HMND; Amarasinghe, YWR
This paper presents about an intelligent service robot named Moratuwa Intelligent Robot (MIRob) that can acquire knowledge through interactive discussion with the user while handling the uncertain information in the user instructions. In order to facilitate this behavior, a finite state intention module has been introduced to manage the interaction between the user and the robot. A set of states has been defined to acquire and update the knowledge as well as in order to perform the actions required to satisfy the user instructions. Dialogue flows and patterns have been defined for each state in order to maintain the interaction with the user. The defined dialogue flows and the dialogue patterns are presented. Furthermore, the concept has been developed in such a way that the system is capable of updating a Robot Experience Model (REM) according to the acquired knowledge. In order to evaluate the performance of the system, experiments have been carried out in an artificially created domestic environment. The capabilities of the proposed system have been demonstrated and validated from the experimental results.
item: Conference-Full-text
Smart irrigation controlling system for green roofs based on predicted evapotranspiration
(Institute of Electrical and Electronics Engineers, Inc., 2016-12) Bandara, AGN; Balasooriya, BMAN; Bandara, HGIW; Buddhasiri, KS; Muthugala, MAVJ; Jayasekara, AGBP; Chandima, DP; Rajapakse, A; Prasad, WD
A green roof is a roof of a building that is covered from a vegetation. Green roofs are beneficial in number of ways for buildings. Crops in green roofs are exposed to direct solar radiation and strong winds. Furthermore, the substrate is shallow and it can hold limited amount of water. Therefore, artificial irrigation methods are required especially for green roofs in tropical countries. This paper proposes a novel irrigation controlling method for green roof based on predicted evapotranspiration. The system is capable of predicting the evapotranspiration and deciding the amount of water to be irrigated based on that. The rationale behind the proposed method is also explained. Particulars on designing and developing a prototype irrigation controller and a laboratory test bed for experimenting with green roofs are presented. Experiments have been carried out and the experimental results are discussed in order to analyze the performance of the proposed system. The experimental results validate the applicability of the proposed system.
item: Conference-Abstract
Synthesizing fuzzy linguistic vocal responses by adapting perception of robot based on visual attention
Muthugala, MAVJ; Jayasekara, AGBP
This paper proposes a method for adapting robot’s perception to produce fuzzy vocal responses about the size of an object based on the visual attention of the robot. In a humanhuman interaction, the humans may use vocal responses, which have qualitative terms such as “small”, “large” etc. The actual quantitative meaning of those terms depends on spatial arrangement of the environment where the attention is focused on. Therefore, spatial information of the environment is analyzed to adapt robot’s perception about the size of an object, which is in its vision field. A fuzzy logic based adaptive method has been introduced to build up relationship between qualitative terms and quantitative meaning. The proposed method is capable of adapting its perception to synthesize vocal responses that have uncertain qualitative terms. It has been implemented and tested on interactive robotic head (IRH). A survey has been conducted using human participants to identify actual human perceptions on test scenarios. Results of the developed system and the survey have been analyzed and outcome statistics are presented.