Social Robots: Human-Like Interaction

Introduction

Social robots can be defined as an autonomous robot that communicates and interact with human beings or other autonomous physical objects using social behaviors and rules that is coded to its role [1]. Social robotics is a new field that embarks on capturing a rich, dynamic nature of social interaction in our environments. This implies that socials skills are needed by the robot so as to allow them to perform a specific task. Some of the characteristics of social robots are that it should show emotions, and have the ability to converse at an adverse level, form social relationships and understand the mental models of their social partners [1]. The social aspect here is important in that it allows communication to take place between the robot and human beings. Social robots should be in a position to work with humans closely in a safe efficient manner that adds value to e people’s lives through helping, caring and entertaining [15]. The application of social robots has been increasing in the last few decades right from our workplaces to families [2]. Based on the survey by the International Federation of Robotics Statistical Department [31], it has been realized that Robots are rapidly moving from the industrial perspective to less structured private ones and it is likely that it will be a companion to the everyday lives of people [3]. It deals with many disciplines that include artificial intelligence, psychology, neuroscience, social and cognitive sciences, machine learning and human-robot interaction [4]. the present study will look into analysis of social HRI from selected social psychology and philosophy so as to come up with a theory on why people are tending to towards social interaction with robots, how to leverage it and the implication to the users and designers [21]. A set of social HRI interfaces will be presented to demonstrate and reflect on the practical feasibility of applying social HRI principles to robot interface designs. The next section will look into the different types of robots, design, impact and challenges associated with social robotics.

Classification of Robots

The classification of robots is based on the environment under which they operate. They are classified as fixed and mobile robots. The two types of robots works under different environment hence having different capabilities [29]. Fixed robots always work in an industrial environment. With the inclusion of sensors to the robot, human-robot interaction has been improved and they are gradually being used in a regulated environment such as in high precision surgery. On the other hand, mobile robots work by moving around and performing different tasks in a large, ill-defined and uncertain environment that is not designed specifically for robots [18]. They deal with situations which are not known in advance and can change over time. Some of such kind of robots are self-driving cars and robotic vacuum cleaners. The human can easily interact with both types of robots as there are no clear tasks that each one of them are required to perform. In particular, the fixed robot is always attached to a tide to a mount on the ground, to allow them to calculate their position based on their internal state. On the other hand, mobile robots majorly depend on their environmental perception in order to compute their location. The three key environments that may require the robots to manipulate are aquatic, terrestrial and drones.

Industrial Robots

This was the first robots to be introduced and they helped ion replacing human tasks to simple repetitive tasks. They can allow factory lines to operate without having to have the presence of humans when they are placed in an environment which is well-defined where the robot will perform specific tasks [3]. The current robots can easily be manipulated into different orientations that can allow them to recognize for instance, how to package things in the right manner. The robots can also be manipulated to transport goods to and from the warehouse hence bringing additional autonomy but the environment that they operate in should still be maintained and adaptable to their operation. During interaction with humans, additional flexibility is required for the robots to perform their tasks and this requires that there should be an introduction of powerful safety needs, both for the robotic arms and for the mobile robots. Specifically, the speed of the robot should be reduced and the mechanical design of the robot should allow the parts to move and it should not be a danger to the user. Allowing humans to work with the robot is important in that each can perform the tasks that they can handle bests [4]. For instance, robots should perform tasks which are repetitive while humans should be subjected to perform a task which are complex with well-designed roles, as they can quickly identify errors and optimize the opportunities.

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Autonomous Mobile Robots

Most of the mobile robots are controlled remotely, allowing them to perform tasks such as aerial photography, pipe inspection, and bomb disposal and majorly relying on the operator remote access to inaccessible areas. For instance, a robot can be subjected to move through a pipe to look for the defects that should be repaired while humans do the repair. Fully automated mobile robots do not depend on an operator but rather they can decide on alone on tasks to perform in a constantly changing environment [4]. Most of the autonomous robots are majorly designed to help the professionals who are working in a well-structured environment such as warehouses. Even in environments that are well structured, robots still share the environment with humans hence their sensors should be very dependable. One of the autonomous robots which is getting much attention this day is the self-driving cars [6]. But it is important to remember that they are very different to develop owing to the fact that they are complex, uncertain environment and also require strict safety requirements. Most of the current robots that are being made are focused in making robots which are more autonomous and this is by improving their sensors as well as more intelligent control for the robot. Having good sensors will help in perceiving things in more complex situations. The robot’s behavior should be more flexible and compliant to allow the robots to learn from humans or adapt to the new situations. This involves sensing and intelligence as well the psychology and sociology of interactions.

Humanoid Robots

They are an autonomous robot which has an extremely complex mechanical design that allows them, to move their arms and locomote using the legs. They are used in research such as the mechanics of walking as well as human-machine interaction. They have been projected to help in executing services as well as keeping in-house space station. Additionally, consideration is being made on how they can be devised to help in providing care to the elderly. It is important to note that they are very expensive to design and control as they are required to have various joints capable of moving in any direction.

Application of robots

In order to understand the importance of robotics education, it is important to look at the roles that robots play in the industry. The roles will help in determining the importance and needs of the robotics education. Research pertaining to industrial robotics allows one to understand the skills needed in the market for employees to be successful on hot to use them. Although there are many robotic applications, possible applications are: Semiconductor industry, Medical industry, Automation production, General part manufacturing, Palletizing. There are different robots that are being used in different application, hence it is important to determine the type of robot and the kind of job that it is supposed to perform so as to optimize the performance. The semiconductor industry robots to make computer chips and components, a production that requires precise movements and procedures that ensures that all connections within the component are not faulty. Most robots being used in making semiconductor are multi-jointed with more than two degrees of freedom. This implies that the robot can reach the same point in space from different angles hence giving the robots more flexibility and versatility in their work area. It is important that computer programmers should write the motion codes for each of the robots based majorly on the aspect of parking. The semiconductor must work under designated cells that must maintain a certain level of sterilization. Robots are also being used in the automotive industry. This is a vast area under which robots can be used for car production as well as fabrication of specific parts. This industry requires multiple degrees of freedom to the robots together with the heavy payload arm. It is important to take attention to the motion tracking system. It has fastened the process of welding the frames in that it only takes 15 minutes to weld fully and glue the car frame together before starting on the next one. The difference between these robots and the one that works on computer chips is that the manufacturing of car frame does not take place in a clean area. The automotive robots are not restricted to only performing lifting of heavy car frames but they can also be used in other areas during the construction of a car. The robots are also used in creating various safety features of the car with the most technical one being the car airbag system. Some of the systems require robotic laser systems. In this case, the robotic arm as if fitted with a laser at the end having a specific pattern that it follows so as to cut out the required pattern into the part. This helps the airbag to easily push through. Just like the airbag system works, the ability for robot’s ton use tools has become more important in various applications. Generally, social robots can be used to make anything. Companies are using them to increase their productivity through the long operation hours that cannot be done by human beings. Although they cannot be used by all industries, there are various industries which have opened up as a result of the ability to use the tools [2]. The company suits the tools in and manner that is specific for their needs. The tools which are available allows the robot to do many different jobs depending on the kind of program which is available. Another important use of the social robot is in place finished parts that should be shipped. It is not a difficult job but rather it increases the volume of product being moved without having too many people doing the work. The robot will not complain about the work or neither will it be tired. In the long run, it helps in reducing the cost of production of the product even though the cost of the robot may be high [6]. The robots being used in this line should be very simple to use to the extent that it should only have one line of motion or it can be complex based on the kind of product being moved. Being that they are simple, makes them very good at performing the jobs. Social robots are also widely used in the medical field. It is important to remember that this industry requires a very strict type of robot in a clean room owing to the fact that there are strict government regulations as it pertains to the medical field. They are used for jobs that require that the jobs should be protected from contamination as possible [5]. This implies that social robots in this field are not meant to lift heavy objects but rather they are designed in a manner that allows them to emit pollutants or have surfaces that can easily collect the pollutants. The operation is that they should clean the room before and after the operation. Getting the correct timing is important hence it is vital to look at the programming of the time down for the step of the process [7]. This is key owing to the fact that robots are used in everyday life such that any mistake can greatly affect the people. From the research perspective, it can be deduced that robots use specific programming methods across all the industries. The most important thing in robotics is the mechanical part. This implies that stress and kinematics analysis should be taken into keen consideration when it comes to mechanical engineering. To design a robot, there should be a great deal of understanding of what the robot is required to accomplish and how the robot will accomplish the task. The robot should be in a position to quickly and accurately complete the task that it is assigned.

By understand ding the various applications of robots in industries, it is evident that there should be people who are well trained on how to handle the robots as well as in designing them. Although they may be expensive, the importance that they give to the industry should be of great consideration. This has been proven in their wide end use within the manufacturing business [7]. Some of the robots are able to perform tasks that cannot be done by humans while there are also robots that can work faster, accurate or without having a break. Because their usage is diverse. It is vital to note that the knowledge required is also diverse right from mechanical, to electrical engineering, to computer science and other different disciplines which are needed for the robots.

Human-Robotic Interaction

Originally, human-robotic interaction (HRI) was outlined by robotic engineering discipline as an "a field of study dedicated to understanding, designing, and evaluating robotic systems for use by or with humans." The study of HRI help in gauging the psychological reaction of robot users so as to describe their evaluations on how human beings interact and collaborate using robot technologies cognitively and emotionally [5]. Although most studies that pertain to social robotic are dedicated to the technical development, research on user’s attitude towards interaction with robots has not been explored much [6]. The attitude of the consumer towards robotic technology can be formulated by looking at both affective and cognitive components. The attitude towards the realization of HRI is highly dependent on human attitude towards communication. Communication is highly influenced by the attitude of the consumers both in terms of their characteristics and appearance. According to the available literature, people prefer communicating with robots whose appearance looks like that of human beings. This, therefore, implies that it is important to incorporate additional functionalities such as social abilities, and nonverbal cues as an important aspect of positive HRI as a means of social exchange. Consumers of robotics always look into the worth of the technology whether it helps in improving their efficiency of tasks, enhance knowledge, increase effectiveness, as well as new means of communication [2]. The social dimension is a powerful tool that is used in engaging users in the communication between humans and robots. Currently, there is a positive user experience that underpins the proliferation of social robotics within our societies and the experience of the user towards social robots should be the key issue of concern. However, it is important to remember that a positive user experience cannot appear by itself hence it must be designed in a more conscious manner and evaluated [9]. The main core of designing and understanding human-robot interaction is the main interest in the field of robotic engineering.

Socially Interactive Robots

High growth is being experienced in the field of personal robots that acts in human-environment results in relation to the social and emotional elements of interaction. Social interactive robots can be defined as robots that social interaction plays a key role. It is important that such kind of robots should display social intelligence, implying that they should show qualities that resembles that of social expressions of human beings [2]. When it comes to social interaction with robots, the research on Human-Robotic Interaction can be categorized as

Robot cognition-centered Human-Robot Interaction

Robot-centered HRI

Human-centered HRI

Robot-centered HRI look into the robot as an independent entity and human as the caretaker of the robot who is responsible in identifying and responding to the needs of the robot. Robot-cognition HRI, on the other hand, views the robot as an intelligent system with the main challenge being on how the robots can be provided with cognitive capacity. Human-centered ensures that the human viewpoint is emphasized and that the issues that relate to the robot design are suitable for humans [3]. All this requires that there should be acceptability and believability, together with expectations of human’s attitudes and perception. These three approaches must be synthesized in order to get robots to “inhabit our living interaction environment”. So far, it is only human-centered HRI which has not received enough attention. The social skills that robots should have requires that they should vary in terms of various dimensions hence those designing robots should be aware of the role and context of the robot and what it is to be used for. The following are some of the dimensions that have been listed.

Contact with human beings

The functionality of the robot

Role of the robot

Requirements for social skills

Social Assistive Robots is a term which is commonly used in the field of HRI and social robots (SR). It involves the use of all robot types that can be used in assisting people with disabilities. There are various applications where they have been used specifically on children with autism, elderly with Alzheimer’s as well as other impairments. The following are some of the existing studies where SAR has been applied Francois et al. (2008) came up with a model of the robot which was capable of adapting its behaviour to detect styles of play of those with autisms in real time. They classified the interaction with robots into two classes: strong and gentle based on the amount of force used by the participant to touch the robot. Five children were used in the experiment to check the effectiveness of interactive styles by looking into both strong and gentle touches and then measure the number of interactions that were recognized by the Aibo robot [8]. It was realized that the robot was able to classify the interaction in real time and at the same time it was also able to adapt to the interaction by altering its own behaviour.

Work Environment and Public Places

There is a growing development of social robotic in our work environments and public spaces. Currently, there are robots used for advertisement purposes in the malls, as waiters in hotels, and even at the banks in Japan. Moreover, there is also utilization of robots in various spheres of public life in the developed countries [4]. The following are some of the reviews on how robots are being applied in various adaptive interactions Svenstrup et al. (2008) reported a field trial by putting FESTO robotic platform at the shopping mall which was able to identify, track and follow individuals naturally. The robot was to roam the mall randomly until it identified an individual. Once it detected an individual, it began to smile as well as play the jingle bell song [4]. The robot would then update its expression and roam again. This study was conducted using 48 respondents and it reported that people had a positive attitude in using social robot in this kind of environment. Reservation was also reported in regard to the distance between the robot and human [42]. Lee et al. (2009) reported on a Snackbot robot which had the ability to autonomously navigate in the hall and deliver snacks to the people. They addressed the challenge associated with the maintenance of long-term association with the robot [5]. They came up with a mechanism for adaptation that could allow the robot to adapt based on the preference of the user and this included snake choice and pattern usage. Later on, an experiment using 21 participants was conducted from which the robot had a role of delivery person for a 4 month period. Results showed that participants had a positive attachment with the social roles of the robot that was beyond the delivery person. The interaction between the robot and participants also ignited new forms of behaviors among the employees that included social comparison and even jealousy. Sekmen et al. (2013) came up with an autonomous mobile robot with the ability to learn how to adapt to the behavioral and preference of the user. The researchers came up with a learning model that was able to allow the robot update itself as it interacted with a user [4]. Various robot capability was used such as face to face detection and recognition, localization and speech recognition [7]. The robot was set up to act as a tour-mate within the university and 25 participants were chosen to help in evaluating the robotic tour-mate in two conditions that were different: adaptive and non-adaptive. It was realized that the participants liked adaptive tour-mate robot as opposed to non-adaptive one. Aly et al., (2013) also reported on the architecture of NAO humanoid robot with the ability to autonomously adapt based on the user’s personality and later on display combine verbal and non-verbal behaviors. An evaluation study was done using 35 participants and it followed the following steps: NAO robot was able to identify the personality traits of the participants, the robot asked participants to pick a restaurant from the available list, the robot to generate speech and gestures [1]. The main aim of the experiment was to find if the robot was able to match the user’s personality and whether it showed a proper gesture that would be viewed as more expressive. Based on the above studies, it is evident that adaptation of robot has been fixed majorly on the preferences of the user in most of the above studies. All the studies stated above have positive findings even though there it draws consideration towards the utilization of other sorts of adaption during HRI in these settings. For example, a person who is advertising some products can forget about a frequent user but in the event that the robot adapts to these parameters, then it may result in positive findings [1]. As a result, it is believed therefore that more research should be conducted on implementing various ways of adapting so as to find benefits. Additionally, more studies should be conducted based on numerous effects of verbal and non-verbal behaviors in a long-term setting and public environments [40]. Although the growth of robotic use is evident in various industries, the robotic education is still in its infancy at the undergraduate level.

Prominent Research Challenges

The study of Human-Robot Interaction has a lot of challenges with some being basic research that explores concepts of HRI in general and others being domain-specific nature that majorly deals with the direct use of robot systems that is involved in the interaction with humans. The following are the vital research challenges within HRI.

Multi-Modal Perception

The most enduring challenge is real-time perception and how to deal with uncertainty [38]. The challenges involved in HRI are particularly complex due to the need to perceive, react and understand human activity in real time. The sensor inputs that are needed for human interaction are larger than other robotic domains and these include, vision, speech which are a challenge for real-time data processing [4]. Additionally, it is still a challenge to understand a dialog system that exists between human users and robots. Even though there are HRI systems which have been implemented, an additional step of generalization is still needed so as to make them work beyond the research lab context [37].

Design and Human Factors

The human factor concern is very important when designing a robot, and this is key in HRI. There is little work that has been done when it comes to robot embodiment. Some work has shown that embodiment has no impact on the emotions of people when compared to virtual agent [5]. Findings have also suggested that there are important differences existing between a robot and virtual agent when it comes to human-machine interaction. More work should be done in order to help in addressing the intricate issues of physical incarnation in HRI [39].

Development/Epigenetic Robots

Epigenetic robotics is the study of cognitive development in robots. It focuses on producing intelligent machines by bestowing them with the ability to separately acquire skills and information [10]. Developmental work involves the design of the primitive for humanoid movements, dialogue, and gestures. Although the area is not a direct subset of HRI research, there is a vital overlap when it comes to the goals of the two areas. It shares much with multi-modal perception and social robotics [1]. The work involves estimating the behavior of a human being’s actions within the broader area of robotic learning.

Benchmark and Ethical Issues for HRI

With the increase in the development of HRI systems, the impact that they create on users and society at large is increasingly being looked into [36]. As per now, no comparison can be made for robotic systems designed specifically to solve different problems. There is the difficulty on how to measure various aspects of HRI [5]. Establishing on whether the robot can make eye contact with the user is simple, but evaluating the reaction of the person and how he/she is affected by the gaze from the robot and behavior is still difficult [34]. Knowing whether the user gets bored or frustrated are some of the difficult questions that have not been answered yet and they are of ethical consideration that should be addressed while developing HRI systems. Some of the challenges that should be measured are unplanned uses of the robot, unintended situations, and permissible tasks that might be met. For instance, in the event that the user requires emergency attention, how will the robot react? Although it is assumed that the user has control over the robot, there are cases that the robot is in control. This, therefore, implies that the issue of authority and control extends to all that is involved with the machine including designers, caretakers, and programmers [5]. More ethical challenges are coming up owing to the fact that HRI systems are growing in terms of complexity and their usefulness, and with the increase of their likelihood to enter into human daily activities [35].

Robot Evaluation

It involves an evaluation of the physical and technological platform which are the benchmark for any particular concern of HRI, and it includes safety and scalability.

Safety

It is an important benchmark for HRI in that it looks at how safe the robot in itself safe, and how it can make it safe for the life of the user [33]. The safety of the robot is the primary concern when it comes to evaluation of HRI system. In the vent that a robot is designed without looking into the safety in kind, then it is likely that it will harm the users and those who designed it [31]. One of the important advantages of HRI over physical assistive robots is how safety risk association is minimized with the physical contact. Safety also looks into the protection of the robot’s user and the robot itself.

Scalability

Most of the HRI work occurs in the laboratory but as they become more widespread in homes, hospitals, and schools, it is important to look at the question of scalability and adaptability. Scalability does not imply that the robots should be designed for a large situation where assistance is needed [25]. The number of people that can be helped with robot should also be looked into. Apart from scalability of the user, the range of usable environments is also a good standard.

Pedagogical Issues

As the innovations help in pushing the industries forward, there are new challenges which are emerging in terms of producing the qualified graduates [32]. Most of the universities lag behind in terms of offering robotic courses. The curriculum is underdeveloped with the main reason being rooted in challenges and the approach being used by the educators in tackling the multidisciplinary subject [39]. There are new fields which have emerged blurring the lines that exist between traditional disciplines. One of the fields that should be studied is nanotechnology owing to the fact that it is a multidisciplinary field [30]. Incorporating the multidisciplinary of this subject into the education systems present various challenges as there is much which is needed in order to manage the depth and focus. Although the multidisciplinary is also important as it brings together the opportunity to interact with different engineers, it is important to work on the challenges associated with the field. Robotic engineering is starting to be introduced in the undergraduate programs and it will help in expanding the field further by having specialized trained people in the field. It is very apparent that there is a gap for the need of engineers needed to work in the in the high technology of the manufacturing industry [28]. In the education sector, robotic has many roles that can help in feeling the needs of the industry. Some researchers have alluded to the fact that robotics should be considered as part of the manufacturing technology [29]. The robotic manufacturing engineering curricula should emphasize the industrial and manufacturing applications if they have to serve the industry in an appropriate manner.

The New Emerging Discipline

The research on robotics has continued to create objects and systems that can help in improving the quality of life. However, the type of knowledge generated from robotic is making a great impact beyond the application of robot [21]. The recent development in robots together with the advanced computing technology has helped in the application of robotic knowledge by creating the robotic system that can operate within an unstructured environment which is occupied by human beings through the provision of service and assistance to humans. Robotics discipline is also being used as a science and it is helping in the production of other disciplines which were not traditionally associated with robotics [24]. Some of this is computer graphics and animations aimed at having a realistic physical simulation of motions and interactions of the moving bodies as they interact and collide with each other. Applications are also seen in the development of motion-based behaviors of the biological and organic materials [27]. Dynamic models of articulated bodies which are being developed are important in realizing motions and for the design required for effective controllers with the need performance in motions as well as interactions [23]. Specifically, the models are important in simulation environments [6]. At the same time, the improvements being seen in biology together with other disciplines is creating a great impact on the development of robotics [16]. The result of the synergy between robotics and other application can be seen in the biometric robotic systems that have mechanical designs which are closer to biological beings as well as the learning capabilities.

Blue-Sky Thinking

Workers are likely to face an unprecedented challenge as they attempt to adapt to challenging situations [13]. In the past, automation technology is getting to be a specialized field which is disrupting one employment sector to the other [15]. The impact of information technology is being felt globally and it is likely to change the way things are done. Virtually, it is expected that every industry will become less labor intensive as the new technology are being assimilated within different areas., the transition is likely to happen rapidly [18]. The major challenge that will be experienced in designing robots will be how to design robots which are flexible enough to keep up with the rapid lifecycles [17]. The trend toward increasing the number of automation in industries is increasing in developing countries.

Recent Trends in Robotics

There are signs showing that the field of robotics is undergoing a major transformation. Companies that earlier on were not interested in buying robots are currently doing so [19]. The design and operational constraints are also being obliterated.

Commercial Investments

The commercial sector is making a significant investment in robotics with google buying several robotic companies [17]. Toyota which is one of the world's biggest car company has announced the introduction of AI and robotics.

Emergence of New International Players

The traditional advances in robots started in Japan, the US, and a few European countries. The field is currently expanding and there are new international players coming in. China is making a great impact on robots. The Chinese are also developing their own low costs robots with the largest commercial drone maker DJI coming from China. Other countries which are investing heavily on AI, robots, and drones are Netherlands, Switzerland and United Arab.

Reduction in Hardware Cost

The cost of buying the robots has also been declining significantly hence allowing for the deployment of robots in new applications with the agricultural sector being a major target [12].

Popularity of drones in civilian sector

Use of drones at the domestic and international level is expected to grow at a rapid rate even though they have a major vulnerability to cybersecurity [10]. The recent hackings of cars is an example of their vulnerability.

Cloud robots

Cloud robotics has the potential of freeing robots from the computing constraints hence allowing drones to have big enough brains.

Leveraging social media

Robots can now access data on social media by mining data using the AI techniques. Social media can also expand their ability in understanding the environment.

Conclusion

The paper has looked into the developments being made towards social robotics and what the future holds. A number of trends have been identified in the increasing application of information technology with the growing economy, care field, and the social importance of robots. Some of the challenges facing the field has been identified including ethics, relationship with humans, as well as the developmental concerns about the professional identity of the social profession. When it comes to the education sector, it is important that the colleges should offer degrees in robotic engineering so that there can be available professions in the field who will be able to help in designing the robots to suit the needs of the companies as well as individual robots. The partitions are required to develop an informed. With the current profession in social education, there are a lot of activities that can stimulate learning about social robotics.

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