Positive Experience Design Strategies for IoT Products to Improve User Sustainable Well-Being

Abstract

Although the advent of the Internet of Things (IoT) technology has benefited the progress of social life, the relentless pursuit of technological advancement cannot definitely lead to a sustainable increase in customer pleasure and happiness. During the design phase, happiness is often overlooked. Therefore, the objectives of this study are as follows: (1) to provide a comprehensive overview of the importance of sustainable happiness for the IoT product design and to propose 15 positive experience design strategies that can improve user happiness; and (2) to apply the 15 design strategies to the IoT product design practice and validate whether they can effectively guide the designers’ work. The research procedure consisted of four steps. First, qualitative data for developing the design strategies was collected through bibliometrics and expert interviews. Second, the propositions of the design strategies were reviewed, analyzed, and constructed using the qualitative research software program NVivo 20. Third, two researchers categorized the 15 strategy concepts into the four directions of positive experience design approaches for the IoT products. Fourth, we conducted a two-week design workshop to validate the feasibility of the design strategies. The results indicate that the 15 design strategies can effectively guide designers to create ideas that prioritize user well-being and allow for creative exploration in various directions. This paper enriches the IoT product design methodology, which can enhance the users’ sustainable pleasure, future goal achievement fulfillment, and social relationship well-being in the IoT era.

1. Introduction

Happiness can be understood as “the experience of pleasure, contentment and positive well-being, combined with a sense that one’s life is good, meaningful and worthwhile” [1]. Improving human well-being is becoming a key societal aspiration, more and more countries are beginning to pay attention to the indicator of national happiness [2]. On this basis, various domains are exploring the possibilities for supporting human happiness and a high-quality of life. For instance, psychology has developed the theory of positive psychology [3]; pedagogy has proposed methods of enhancing students’ happiness [4]; and economics has explored the factors that influence socioeconomic well-being [5].

In the design sector, researchers have also widely thought about how design can contribute to well-being. In other words, exploring how design can support humans in their pursuit of a pleasurable and satisfying life [6]. Desmet proposed the concept of positive design based on the research on subjective well-being, which is, that aimed to design to bring experiences that are both pleasurable and have a long-term positive impact on individual development during a person’s interaction with a product or service [7]. Moreover, researchers have developed several frameworks and approaches to facilitate positive experiences [8,9,10]. However, it is important to note that these research are too widely applied, which means that there should be different product categories based on different design intentions [11], such as the factors affecting positive user experience in a workspace being different from a leisure space; medical products being different from household products; and educational systems being different from e-commerce systems. Therefore, in contrast to other studies, our research is dedicated to the development of domain-specific methods.

Technological advancement does not equal happiness for people [12,13]. Although the IoT technology has advanced significantly and has actively enhanced life through its high level of automation and intelligence, it has also heightened tension and pressured consumers to adopt new technologies [14,15]. Moreover, as new technologies emerge, rapid product modifications occur, leaving individuals psychologically isolated and negatively impacting their physical and mental health [16]. These occurrences can be attributed to the designers and engineers who believe that technology alone can enhance societal well-being, neglecting the study of happiness—a complex psychological factor. Thus, in the Internet of Things (IoT) era, technology has both positive and negative effects on personal well-being while fueling economic development [17]. However, there are fewer explorations of methods that enhance user happiness within the IoT domain, and less research on how to prolong positive user experiences and achieve sustainable user behavior at present.

Therefore, the objective of this paper is to find how to improve users’ sustainable well-being in the IoT product design. In order to achieve this, the main purpose of our research is to propose positive design strategies for the IoT products. Secondly, this research is performed to verify whether these strategies can effectively guide designers in the design process and to understand which are the more feasible strategies in practice.

The subsequent sections of this paper are structured as follows. First, the Section 2 reviews relevant research carried out on the IoT products, sustainable well-being, and positive experience design approaches. Second, the study part constructs a positive experience design strategy for the IoT products through a qualitative study. The second part of the study validates the potential and feasibility of these design strategies through a design workshop. Next, we discuss the findings of this paper and the academic and practical implications of the study. Finally, the limitations and future directions of this study are discussed.

2. Literature Review

2.1. Internet of Things (IoT)

The Internet of Things (IoT) was first proposed by Kevin Ashton in 1999, and then became increasingly recognized [18]. It adds computer logic to a large number of items or objects for intelligent identification and management in order to interconnect people, machines, and things at any time and in any place [19]. To date, the IoT research have focused on three broad areas: on the IoT technology sectors; exploring possible applications and systems; developing middleware and an infrastructure; and suggesting ideation methods [20,21,22,23]. In the IoT security sector, there was a focus on exploring factors affecting the IoT security, on proposing frameworks for dealing with security challenges, and on proposing or utilizing a number of security techniques and approaches [24,25,26]. In the IoT applications areas, it helps monitor health parameters and drug intake to improve medical quality and save lives, it creates a safe and comfortable home environment; it also monitors air quality, identifies emergency routes, and promotes urban greening [27,28,29,30]. These studies provide insights into the IoT technology and applications, as shown in

Table 1. Literature on the internet of things.

Research Areas	Authors	Contributions	Source
Technology	Georgakopoulos	Presented global IoT device discovery and integration.	[20]
	Kubitza	Presented an IoT prototyping platform.	[21]
	Gianni	Introduced a software toolkit and promotes the IoT systems.	[22]
	Shahzad	Proposed a framework to fulfill user requirements.	[23]
Security	Gias Uddin	Offered the results of preliminary study of the IoT developer discussions in the IoT security.	[24]
	Tawalbeh, L.	Explored the background of the IoT systems and security measures.	[25]
	Neshenko	Focused on the ever-evolving IoT vulnerabilities and provided a unique taxonomy.	[26]
Applications	Kubitza	Introduced an infrastructure for home and offices.	[27]
	Plageras, A.P.	Designed a “smart healthcare-room”.	[28]
	Yingying Jiang	Generated sensing fabric in combination with a smart city.	[29]
	Mano, L.Y.	Exploited the IoT to enhance a health smart home.	[30]
Positive user experience	Minji Cho	Discovered that data on the IoT product interface might increase a user’s confidence.	[31]
	Hjelm	Proposed that a good monitoring system may make a user more autonomous and comfortable.	[32]
	Zhang, et al.	Conducted research on the correlation between IoT devices and user intent and developed a strategy for a positive experience.	[33]
	Navarro-Alamán, et al.	Proposed that predicting emotions through IoT data could enhance user satisfaction	[34]

.

Moreover, a number of recent studies address the importance of positive user experience. Minji performed a qualitative study, which lasted four weeks, on the process of consumers utilizing IoT devices and discovered that data on the product interface might increase a user’s confidence, and that safety information is beneficial for increasing overall satisfaction [31]. Hjelm analyzed the IoT technology used in elder care institutions from a user’s perspective. While a good monitoring system may make a user more autonomous and comfortable, it was revealed that a sensor notification system could consistently produce favorable emotions in the user [32]. Atsushi conducted research on the correlation between the IoT devices and user intent. To develop a strategy for a positive user experience, he collected log data from users who remotely managed home appliances using their cell phones [33]. Lacuesta proposed that predicting emotions through the IoT data could enhance user satisfaction. To achieve this, an IoT recommendation system was developed to monitor the user’s status [34]. These studies offer insights into what factors influence a positive user experience during their use of an IoT product. However, these factors are usually singular or dispersed, and it is difficult to guide the specific design of work. In addition, this research focuses more on positive user experiences in the moment and does not start from the perspective of sustainable well-being. Therefore, our study focuses not only on the user’s pleasure in the moment but also on the long-term positive experience, which is not only conducive to individual pleasure but also to collective harmony.

2.2. Sustainable Well-Being

One of the seventeen sustainable development goals proposed by the United Nations is good health and well-being [35]. Well-being is a key sustainable development goal and a fundamental requirement for good health [36]. Therefore, increasing sustainable well-being is an important topic of research. Lyubomirsky suggests that “sustainable happiness” is possible [37]. This implies an increase in and subsequent maintenance of an individual’s internal well-being. Waterman likewise believes that happiness is sustainable because the opportunities for enhanced eudaimonia, self-actualization, and potential development are limitless and thus easily maintained [38].

Traditionally, sustainable development was based on the three “Es” of economy, equity, and ecology, emphasizing present and future generations’ rights to enjoy the environment and natural resources [39]. Psychologically, sustainability is viewed not only in terms of the ecological and social environment but also in terms of promoting well-being [40]. At present, various fields are conducting research on how to improve sustainable well-being. The psychology of sustainability emphasizes sustainable well-being through the promotion of relationships and positive narratives in everyday life [41]. Schnell proposed that whether at work or in life, if people can gain meaningful experience in many challenges, transformations, and changes, their happiness will be more sustainable [42]. Nong L proposed that emotional and cognitive engagement in the field of education is more conducive to reducing the work pressure of teachers and promoting sustainable well-being; thus, bringing sustainable passion, pleasure, and well-being to their current and future lives [43]. However, in the field of the IoT product, there are few studies focusing on sustainable well-being. This paper will address the question of how to prolong the positive user experience and achieve sustainable well-being in the IoT product design, aiming to realize what contributes to a sustainable and smart life.

Table 2. Literature on sustainable well-being.

Authors	Contributions	Source
Lyubomirsky	Proposed that “sustainable happiness” is possible.	[37]
Waterman	Believed that happiness is sustainable.	[38]
WCED	Emphasized sustainable well-being through the promotion of relationships and positive narratives in everyday life.	[39]
Schnell	Gained meaningful experience in many challenges, transformations, and changes, through which their happiness will be more sustainable.	[42]
Nong L.	Proposed that emotional and cognitive engagement in the field of education is more conducive to reducing the work pressure of teachers and in promoting sustainable well-being.	[43]

presents some research details on sustainable well-being.

2.3. The Approaches of Positive Experience Design on IoT Products

In a previous study, we provided approaches for designing IoT products that promote positive experiences (see Figure 1), which can help enhance consumers’ sustainable well-being [44]. These approaches focus on two key elements: the design of the object and the sources of well-being. The design can take four directions: individual pleasure experience; personal goal realization; group need satisfaction; and group relational harmony. Each direction can contribute to a positive experience with IoT products and enhance consumers’ subjective well-being. This paper provides a comprehensive design strategy based on previous research. The strategy aims to help designers achieve four design goals that can lead to intentionally increasing happiness through IoT product design. The four directions of the approach are explained as follows:

• Individuals’ pleasure experience: to achieve the purpose of enjoying a happy experience through positive design, which is when individuals obtain subjective well-being through short-term happiness;
• Personal goal realization: to obtain subjective well-being through the realization of long-term goals with personal significance. Design is no longer concerned with short-term happiness; it focuses on achieving long-term goals and aspirations;
• Group need satisfaction: for the design to pay more attention to the collective’s meaning and power, as well as to balance the conflicting personal values of collective members, in order to meet the experience needs of each member of the collective family as the design goal;
• Group relational harmony: to create a nice collective atmosphere through positive experience design, that is, foster collective harmony by mobilizing active dialogue among group members through the design of an IoT device.

3. Study 1: Construction of Design Strategies

3.1. Method

According to Jaccard and Jacoby, theoretical assertions can be developed based on the literature studies, experimental testing, or other theory validation procedures [45]. This study gathered qualitative data through bibliometrics and expert interviews to support our argument. We then analyzed the data to draw our conclusions. To gather the relevant literature, we searched the Web of Science using keywords, such as “IoT Design Method”, “IoT Emotion”, and “IoT User Experience” from the past decade. We further analyzed the data using the qualitative research software NVivo, including word frequency and qualitative analysis. The results were presented in visual form using Sankey diagrams. Next, we interviewed eight experts from various fields, all related to IoT products, such as product design, interaction design, and industrial design. Through their insights, we comprehensively understood the topic from different perspectives. During the interview, the experts went through three stages to ensure they could provide accurate and practical methods within the given time limit. These stages included sensitization, interviews, and discussions; and completing records in questionnaires. After conducting literature research, the data was coded in NVivo to ensure its validity. In sum, it collects qualitative research data from theoretical and practical perspectives to create a more realistic design plan. Figure 2 depicts the methodological process.

3.2. Data Analysis

We first conducted a literature keyword search and found 202 relevant articles. After organizing the literature data, we screened 80 publications and performed qualitative analysis and word frequency extraction to develop the design strategies for the IoT devices. We transcribed and analyzed the expert interviews for general concepts, resulting in 98 data points that were usable. By merging similar data codes and comparing the contents of each data point in NVivo, we coded a total of 45 pieces of data. After analyzing information from various sources, 15 strategies for designing positive experiences with IoT products were created. Figure 3 and Figure 4 depict the analytical procedure.

Based on academic data analysis, we found that the current literature mainly focuses on the concepts of anticipating users’ intents and perceiving behavior change. In the concept of perceiving behavior change, we coded a total of 11 pieces of data in the literature. For example, Perumal proposed that users’ behaviors and needs may vary due to changes in time, space, environment, and personal preferences; and that IoT products are able to sense changes in users’ status in a timely manner by means of sensors, and then make corresponding feedbacks after data analysis [46]. A total of 12 data were encoded in the concept of anticipating users’ intents, and several studies have focused on suggesting that the IoT technology can not only sense emotional changes through sensors, but also memorize recurring user behaviors and complete predictions of daily life. For example, Huang ZH proposed an IoT system based on multimodal features which calculates user preferences for items and predicts and recommends items that match user preferences [47]. However, in the matter of strengthening interactive communication, only 2 pieces of literature evidence were coded, and we found that most of the literature is about the use of the IoT technology to pursue new services rather than the enhancement of existing services. In fact, the IoT technology brings ways of interaction that can enhance the communication between the product and the user, so that the user enjoys the experience more rather than replacing the experience. There were also only 2 pieces of data encoded in the concept of creating collective memory. The reason behind this could be that current research focuses more on individual memories rather than a collective perspective. Da Rocha suggests that by creating a collective experience for members, the process of recalling this shared experience later can increase the sense of belonging to the collective [48]. In addition to this, ample literature research has contributed other concepts.

Unlike in the literature study, the content provided in the expert interviews focused on the topics of multi-dimensional sensory experiences and data-driven management of life; two strategies that experts believe can be better applied in practice to enhance positive user experiences. For example, expert P5 argued that when users use a product, they tend to want to complete tasks in a more interesting and immersive way, and that the IoT technology can enable a more immersive experience by combining multiple senses, such as auditory, visual, and tactile senses. Expert P8 suggested that the use of IoT devices to access safety data about the body and environment; and through features such as automatic alerts, health monitoring and remote monitoring, could give users a sense of physiological and psychological safety, leading to a sustainable sense of well-being. These two strategies have also been extensively researched in the literature, for example, Safari Bazargani proposed a multi-sensory IoT media architecture that provided users with realistic media content to increase their positive experience [49], and Yoon S proposed the use of IoT technology to collect and categorize life data as a way of monitoring and managing the user’s life status [50]. In addition to this, other concepts were also well supported by the expert interviews, for example, expert P4 proposed to set up autonomous object-to-object connections according to the different needs of the members, and expert P1 also proposed to apply the DIY approach to the IoT products to inspire users to explore more possibilities of the products and prolong the enjoyment of experiencing the products, which were coded in the subject of autonomous functional-setting relationships. Overall, both the expert interviews and the literature study proposed effective strategies for achieving sustainable well-being from different perspectives, just with different emphases.

3.3. Results

We identified 15 main concepts after reviewing the records, the coding, the organization of the article material, and the expert interviews. Based on the above data results, we categorized 15 design strategies into 4 design directions for IoT products’ positive experience design approach. After several group discussions, we reached a decision. Figure 5 displays the finalized concept diagram.

3.3.1. Design Strategies for Individual Pleasure Experience

• Strengthening interactive communication

Using the IoT technology to improve the connection between users and products can lead to exciting new interaction methods; spark user interest in experiences; and enhance overall usage enjoyment. There are different ways to enhance communication between the user and the product, such as voice, action, and visual interactions.

• Multi-dimensional sensory experiences

One significant difference between IoT items and traditional products is their advanced intelligence and automation abilities. IoT technology can combine hearing, vision, and touch to cater to the diverse entertainment needs of users and deliver a peaceful user experience.

• Anticipating users’ intents

IoT technology can gather information about users’ intentions in advance and observe and remember their repeated actions to predict their daily routine accurately. This makes smart devices function like a “digital companion” similar to friends or family members.

• Perceiving behavior change

IoT products are designed to adapt to changing user behavior through a high degree of automation instead of requiring users to adapt to the product. The system can detect any changes in the user’s state in real time by using sensor technology. Based on data analysis, the system can provide feedback and adapt to the user’s changing behavior patterns.

• Data-driven management of life

Leading a data-driven managed life offers the user physical and psychological security. The IoT device transfers information about the environment, such as lighting, heating, ventilation, and air purification to the user. Based on this information, automatic commands or feedback can be executed.

3.3.2. Design Strategies for Personal Goal Realization

• Monitoring target process

The product’s progress will motivate the user to complete their tasks diligently. Through visual means, IoT technology can effectively gather information on progress towards a target, empowering users with a greater sense of control and assisting in attaining personal goals.

• Stimulating interest in the target activity

Employing IoT devices to stimulate users’ goals and values can be enhanced by integrating more appealing technologies. It allows users to actively achieve what they desire and increase their interest in set activities, resulting in an extended pursuit of goals.

• Managing target activities

IoT extensive data analysis can perform various tasks, including gathering, processing, analyzing, visualizing, and implementing data. Once personal objectives have been digitized, a reference plan can be created by storing, processing, and analyzing data. This plan can help users better plan and achieve their goals.

3.3.3. Design Strategies for Group Need Satisfaction

• Modular portfolio model

Modularizing products is based on user needs. This approach allows IoT products to serve multiple purposes, making them adaptable to various user requirements. It enhances functionality without creating complicated structures, and users can easily switch between functions as needed, responding flexibly to changes in their needs.

• Autonomous functional-setting relationships

Users can turn IoT items into DIY projects, giving them the freedom to create a connection method that suits their specific needs. This approach is flexible and can be easily adapted to changing needs, while also addressing community needs and encouraging individuals to take on complex challenges independently. Moreover, this approach can have a positive impact on others.

• Balancing value conflicts

A communal environment is a place where people have different emotions, behaviors, and beliefs. IoT technology is utilized to fulfill individual needs and also detect and analyze group conflicts to reduce their frequency and impact.

3.3.4. Design Strategies for Group Relational Harmony

• Acquisition of collective honor

The intelligent home system provides real-time feedback on energy usage, making consumers more conscious of their resource consumption. It helps members become better managers of their resources; increasing interest in public welfare activities; and creating a stronger sense of family. Working towards a shared goal using IoT devices in a group setting can promote unity and striving for a noble societal objective can create a feeling of pride.

• Creating collective memory

Memories usually elicit more pleasurable feelings than experiences. IoT devices may create and exchange collective memories to increase group connection; the user’s sense of belonging to the group; and preserve the shared memory.

• Improving information sharing

Having a common interest can create a positive social and family environment. With the help of IoT technology, sharing knowledge, information, and resources becomes more accessible, allowing members to connect and bridge the gap between each other.

• Caring for each other

When group members care for each other, the atmosphere can become positive. IoT products should prioritize not only intelligence and automation but also human-to-human communication. It can encourage users to care for and influence others, ultimately leading to better health for the entire family.

4. Study 2: Concept Generation Workshop

The aim of this study was to test the effectiveness of 15 design strategies in promoting concept generation, particularly in short-cycle design workshops. To achieve this goal, the study employed 22 product designers and organized a 2 week design practice to evaluate the usefulness of these strategies from the designers’ perspective.

4.1. Participants

Participants were recruited from the School of Design and were product design students. Since understanding and using design strategies to complete an IoT product design was the core task of the study. Participants were selected based on the following criteria: they had some familiarity with IoT products; they all had experience in several university-enterprise co-operation projects; and they were able to complete the conceptual design of the product independently. Eventually, we recruited 22 design students to participate in our workshop, including 8 undergraduates, 5 postgraduates, and 9 PhDs, as shown in

Table 3. The information about the participants.

Gender	Undergraduate	Master	Ph.D.	Total
Male	5	3	3	11
Female	3	2	6	11

.

4.2. Design Assignment

The concept of this design is an IoT house with a family comprising of three generations (including the elderly, adolescents, and children) as the focus. The positive experience design approaches and IoT product strategies were used as tools to guide this design assignment. All participants worked together to complete the design task within 2 weeks.

4.3. Procedure

Prior to the design phase, the author explained the strategies of positive experience design for IoT products and shared 15 design strategies with the designers. During the focus group, the author addressed each participant’s concerns and ensured they understood the research approach used in the study to effectively complete the design exercise. Designers were tasked with presenting their concept sketches after applying the strategies to develop their ideas. Additionally, we held idea exchange meetings every 2 days to facilitate discussion and exploration of better design solutions.

4.4. Strategy Evaluation

We used a combination of participant scores and subjective evaluations to determine the effectiveness of design strategies in aiding concept development. To assess satisfaction with the design strategies, we distributed a questionnaire at the end of the design work, asking participants to rank their satisfaction on a 7 point Likert scale ranging from “not at all satisfied” to “very satisfied.” After ranking their satisfaction, we asked participants to explain their reasoning. We further asked five open-ended questions to gauge the simplicity, originality, and innovativeness of the ideas, and participants could combine their responses to explain their ratings. Additionally, we asked whether the method helped with expressing design concepts and communicating with other designers, as well as whether it contributed to the overall design atmosphere.

4.5. Result

4.5.1. Design Concept

After 2 weeks, the designers created a total of 15 design concepts for IoT products that follow positive experience design strategies (Figure 6). The following are some examples of the results:

• A smart coffee machine is designed on the basis of strengthening interactive communication. Users can start the coffee machine with a smile, and interesting interactions enhance the user’s sustainable pleasure.
• The use of multi-dimensional sensory experiences in game scene design, where IoT technology overlays different sensory designs of lighting, earphones, and seats to provide users with a more immersive experience.
• The bathroom scene is designed with the strategy of anticipating users’ intentions. When the user arrives home late from work, the IoT technology can gather information in advance and prepare warm bath water for the user, providing care as though they were relatives.
• The living room scene incorporates the strategy of perceiving behavior change. When the elderly watch TV and fall asleep unintentionally, a sensor in the living room can detect the change in the user’s status based on the breathing rate and immediately turn off the TV.
• The strategy of data-driven management of life is used to manage the daily resource consumption of the home. Energy data can be automatically generated and sent to customers’ mobile phones via the IoT, providing users with a sense of security for environmental data.

4.5.2. Designers’ Feedback

Once the workshop was completed, the users’ scores and opinions on the strategies were gathered (Figure 7). The data was analyzed, along with the reasons behind the scores.

Most participants were keen on using the 15 positive experience design strategies for IoT product development as their average satisfaction rating was above 4. The design criteria that received the highest scores were multi-dimensional sensory experiences (6.267), the strengthening of interactive communication (5.978), and the perception of behavior change (5.867). Designers found that adopting these strategies made it easier to generate original ideas and led to unexpected inspiration during the design process. They also believed that the strategies of anticipating users’ intents (5.178) and data-driven management of life (5.244) would help develop more future-oriented and abstract conceptual solutions. Additionally, it was important to consider usability when implementing these design strategies.

Out of the three strategies for personal goal realization, monitoring the target process (5.733) received the highest rating. While the design strategies were clear enough to provide a solid guideline, some designers believed that making the approach to the goal more transparent could be beneficial. However, if this transparency had negative consequences, it should be used responsibly by different groups of users. Managing target activities (5.600) received a higher grade than 5 due to its practicality; relevance to user needs in real-life scenarios; and potential for comprehensive design solutions. In terms of stimulating interest in the target activity (4.933), some designers believed that it could be challenging to motivate users and generate design ideas quickly.

Designers preferred autonomous functional-setting relationships (5.800) as the most popular of the three design strategies that aim to satisfy group needs, with a significance of 55.6%. Building functional relationships between different products is like putting together building blocks which generate design ideas and improve the design atmosphere. Designers quietly experiment with different combinations, encouraging each other in the exploration process, leading to a positive design atmosphere. Designers who scored less than 4 in the evaluation of balancing value conflicts (5.044) believed that this concept was challenging to grasp and not as flexible as other strategies.

Designers believe that prioritizing care for each other is essential (5.556). They also found that the design strategy of influence was the most effective for group relational harmony. Other creative design methods that were helpful include the improvement of information sharing (5.422) and the creation of a collective memory (5.222). By addressing previously overlooked challenges and incorporating them into their designs, designers were able to come up with innovative concepts that were highly appealing to both designers and users. This created a sense of connection between them.

5. Discussion

This paper presents 15 positive experience design strategies for IoT products that designers can use to improve sustainable user well-being. It was found that some strategies were highly rated (e.g., strengthening interactive communication, multi-dimensional sensory experiences, perceiving behavior change) while others were not as highly satisfying (e.g., anticipating users’ intent, data-driven management of life), but obviously the reported research clearly shows that all 15 design strategies do help designers generate design inspiration that focuses on positive user emotions.

Why should we invest time and effort in the IoT product design process to focus on user well-being? According to Kowalski’s proposal that positive emotions contribute to sustainable product usage behaviors, both the product itself and the positive emotions evoked by the product help to extend the cycle of its use [51]. In this regard, design researchers have also hypothesized that encouraging user attachment to a product will decrease continuous consumption and protect the ecological environment [52,53]. Our insights can therefore help designers to focus on the positive emotions of well-being as a means of stimulating sustainable product usage behaviors, while also contributing to the research on the achievement of sustainable transformation of society and human well-being.

We can also see that this paper offers two contributions to the literature. Firstly, we provide a comprehensive overview of the importance of user happiness, or positive experience of IoT product design. Previous studies in the literature have focused more on the advancement of IoT technology, but as stated at the beginning of the article, technological advancement does not mean human happiness [12]. Although technology has made great advancements, people are not necessarily happier than they were 20 years ago [54]. Thus, we suggest that “happiness” should be taken into account in the design of IoT products, as advocated by positive computing, “using design and technology to enhance human happiness”. Secondly, our study proposes positive experience design strategies to support the design of IoT products. Prior literature has only emphasized the importance of individual factors for positive user experience, such as aesthetics, relevance, popularity, and security [55]. However, such singular factors do not specifically guide design efforts or achieve the goal of prolonging user happiness. Therefore, our work takes a step towards a systematic design strategy by proposing 15 design strategies that can effectively enhance user happiness through the 4 directions of positive design, namely, individual pleasure experience; personal goal realization; group need satisfaction; and group relationship harmony, which contribute to the research based on the design methodology of IoT products.

Our research makes an equally significant contribution to practical work. These strategies can be a complementary approach for IoT product designers or students. Design methods can broaden designers’ minds, enhance reflection, and support design behavior. In preparation for the design workshop, we learned that some design students realized the importance of evoking positive emotions for users, but there were no available tools to stimulate creativity; moreover, they struggled to find specific design strategies to guide their design work. The design strategies we developed provide a conscious method to the designers, helping them manage to promote user well-being, and by making problem solving from both individual and collective perspectives possible.

6. Conclusions, Limitations, and Future Research

While most research has focused on the advancement of IoT technology, this paper proposes 15 positive experience design strategies from the perspective of sustainable user well-being, as well as validating the applicability and innovation of these strategies in design practice. This research paper proposes IoT product design strategies through evidence from both empirical literature and practical experience and combines them with previous research work on positive experience design pathways to achieve a complementary approach towards design in the IoT domain. The findings provide design inspiration to guide the design process of IoT products and inspire designers to think about focusing on user well-being from multiple perspectives.

Our study aims to present IoT product design strategies that can be used by designers, but it is limited in that we only selected design students to use these strategies and to collect feedback. The design strategies may be evaluated differently by product designers in companies, as designers have many years of experience and may have a different level of understanding of the design strategies than the students, as well as their resourcefulness in projects may also be biased. In addition, there may be dimensional variability between these strategies, with design students perceiving one part of the strategy to be more abstract, which provides a wider scope for thinking and generating unexpected ideas. Whereas another part of the design strategies was more figurative, which was easier to understand and to use relative to the abstract strategies, enabling rapid generation of design concepts. Therefore, the variability of the evaluation results also encourages us to continue to improve these strategies in future studies to enhance the consistency of the methodology.

The 15 strategies proposed in this paper are considered to be the starting point for further research. The next step is to conduct more empirical validation of these strategies; apply them to design work in more enterprises; attract more designers to use them; and collect more suggestions in order to transform them into a mature IoT product design methodology. We envision the following plan: (1) conduct a controlled experiment in which student designers and enterprise designers use the strategy to complete the design of an IoT product and collect feedback from all groups to verify if the strategy is universally feasible; (2) collaborate with a company to develop an IoT product, where the corporate designers complete the design work using the 15 strategies, and after the product is produced and placed on the market, collect feedback from users; after all, the information whether users get the sustainable well-being is the most reliable; and (3) in the future, to commit to developing more design methods that extend positive user experiences and to conduct research for more product types. The strategies we propose will be very useful for corporate practice in future research work, and we are committed to developing methods that truly benefit the designers’ work.