Dual-user crib design based on the SAPAD model

Abstract

To meet the needs of mothers and babies for using baby cribs, this study established a product design process integrating SAPAD theory and the Analytic Hierarchy Process (AHP) from the perspective of maternal-infant lifestyles. Information on mother-baby lifestyles obtained from user studies was analyzed through the SAPAD framework to examine the deep meanings of parenting behaviors and key crib-usage behaviors across different contexts. Cluster analysis and AHP were combined to first generate symmetric clustering matrices identifying meaning clusters, then conduct weight analysis with consistency testing to extract users’ core design needs. A core meaning model was constructed to identify corresponding key behaviors and correlates, ultimately yielding five major design modules that translate user requirements into crib design concepts. Design analysis and practice implemented these guidelines, with fuzzy AHP verification confirming the method’s effectiveness in guiding crib design. This approach provides an efficient user-centered model for functional modularization in baby cribs and other multi-user products, effectively resolving demand transformation and functional division challenges in multi-user product design.

Full Article

Dual-User Crib Design Based on the SAPAD Model

Yanfeng Miao  ,^a,* Yi Zhao,^a Yan Zhao,^a and Wei Xu ^b

To meet the needs of mothers and babies for using baby cribs, this study established a product design process integrating SAPAD theory and the Analytic Hierarchy Process (AHP) from the perspective of maternal-infant lifestyles. Information on mother-baby lifestyles obtained from user studies was analyzed through the SAPAD framework to examine the deep meanings of parenting behaviors and key crib-usage behaviors across different contexts. Cluster analysis and AHP were combined to first generate symmetric clustering matrices identifying meaning clusters, then conduct weight analysis with consistency testing to extract users’ core design needs. A core meaning model was constructed to identify corresponding key behaviors and correlates, ultimately yielding five major design modules that translate user requirements into crib design concepts. Design analysis and practice implemented these guidelines, with fuzzy AHP verification confirming the method’s effectiveness in guiding crib design. This approach provides an efficient user-centered model for functional modularization in baby cribs and other multi-user products, effectively resolving demand transformation and functional division challenges in multi-user product design.

DOI: 10.15376/biores.21.2.3369-3393

Keywords: Baby crib; Dual-user demand; Lifestyle; User research; Design Methodology

Contact information: a: College of Furnishings and Industrial Design, Nanjing Forestry University, Nanjing, China; b: Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, China; Corresponding author: myf1203@163.com

INTRODUCTION

With evolving consumption concepts and transformations in infant care needs, contemporary mother-baby groups prioritize personal well-being and scientific childcare more than traditional childcare approaches. Demand for maternal-infant products and services is diversifying, with growing pursuit of premium experiences and substantial market potential for high-end infant care products. In the competitive baby crib market, comprehensive user research constitutes the critical foundation for design innovation and product success. Product design is significantly influenced by lifestyle evolution, making development from maternal-infant lifestyle perspectives essential for enhancing user experience (Jabbar et al. 2019). Lifestyle represents a comprehensive manifestation of daily interests, concepts, behavioral tendencies, and characteristics of individuals or groups. A reciprocal relationship exists between lifestyle and product design: lifestyle changes drive product iteration and updating, while product innovations correspondingly influence lifestyles (Zhang 2023). Consequently, profound understanding of lifestyle transitions is crucial for infant product design.

The concept of lifestyle was first introduced by American psychologist Alfred Eckler in 1927, who maintained that lifestyle represents a distinctive pattern of living that emerges only when humans occupy specific social and cultural contexts. In 1963, William Lazer (1963) incorporated lifestyle research into marketing studies, proposing the AIO model whose primary variables are consumers’ activities, interests, and expressed opinions. This framework clearly reveals the significance and value of lifestyle research by explaining user actions through psychological trait reflection. It has progressively become one of the most essential tools for identifying market segment demands. Liu’s “Lifestyle Form Model” in design science provides a reference framework for transitioning from life forms to product design. This model systematically connects people, needs, behaviors, events, new tools, new methods, and conceptual design while deeply analyzing their logical relationships (Fei 2022). Li and Sun (2018) completed a preliminary exploration of smart pram innovation by studying infant lifestyles and analyzing observational data from six infants’ daily living conditions using the semiotic approach of the product architecture design model.

In crib product design, current trends emphasize enhanced humanization, intelligence, and environmental sustainability. Humanized design prioritizes infant and family needs through features such as height-adjustable, disassemblable, and convertible cribs to enhance usability. Cao and Deng (2019) employed computer-aided innovation with TRIZ theory to identify improvement priorities and resolve technical conflicts in growth-adaptable pram design. Intelligent cribs enable app-based control of temperature, humidity, and sound to improve infant sleep quality (Kaittan et al. 2020; Hotur et al. 2021; Pratap et al. 2021). Kim and Cha (2021) surveyed limited professionals and targeted users on smart cradle development, evaluating form, functionality, stability, colors, and finishes for baby communication technology—though constrained by small sample size and insufficient price analysis. Ferrara and Russo (2018) proposed three customized IOT solutions for infants/parents in educational contexts, highlighting intelligent implementation while fostering emotional engagement within everyday aesthetics frameworks. Sustainability advances include natural materials and paint-free processes. Key research areas cover neonatal care, sleep safety (suffocation risks, positioning, fall prevention), sleep difficulties, and patterns—with newborn care linking to incubator design (Arnoldov 1892; Ball et al. 2021). Emerging studies explore smart cribs with cry recognition and remote monitoring/soothing via cameras.

Infant sleep is initially regulated primarily by intrinsic mechanisms, characterized by prolonged yet fragmented sleep patterns. As infants reach 12 to 16 weeks, circadian rhythms gradually develop. Parental behaviors in sleep care—including sleep habits, bed selection, bedtime routines, and responses to nighttime awakenings—profoundly impact infant sleep architecture and quality. Through household questionnaires, Yin and Xi (2023) found that 29.7% of families required infant care guidance, with particularly significant needs in responsive care and early learning support. Baddock et al. (2019) documented physiological and behavioral differences between co-sleeping and independent crib-sleeping infants: increased nighttime awakenings, elevated bed temperatures, extended breastfeeding duration, and variations in sleep architecture, cardiorespiratory control, and stress cortisol responses. Liu et al. (2022) investigated sleep patterns in 0 to 35 month-olds via regression analysis, identifying that napping practices, co-sleeping, and parental presence during naps correlated with age and breastfeeding status; frequent napping significantly increased nocturnal awakenings. Wang et al. (2021) used paired t-tests and Wilcoxon signed-rank tests to compare paraspinal, abdominal, and lumbar erector spinae electromyography in tilted versus flat mattresses, finding elevated trunk muscle activity and abdominal engagement in prone positions on inclined surfaces—potentially increasing fatigue and suffocation risk if infants cannot self-reposition themselves supine. Consequently, sleep safety demands heightened attention due to infants’ underdeveloped physiological systems. Since family sleep practices critically determine infant sleep outcomes, crib design should assist parents in cultivating healthy sleep habits to enhance sleep quality.

This study aimed to combine the product with the living environment, take the family structure as a unit, explore the lifestyle of the new generation of mother and baby users, analyse the forms of living activities and behavioural characteristics by combining qualitative and quantitative research, explore the hidden needs of mother and baby users, and achieve innovation in the construction of baby bedding products. The goal was to obtain a new and more reasonable product architecture and modules to guide the development and design of baby bedding. Through in-depth analysis of the basic characteristics of mothers and babies, as well as detailed research on existing baby crib products, combined with the study of user behaviours generated in the process of mothers’ childcare, the study applied the design process established based on the semiotics approach of product architecture design (SAPAD) model to design, and ultimately obtain a crib design. The result is intended to meet the needs of users, in order to provide detailed childcare conditions, to promote the intimacy of mothers and babies, and to soothe the sense of fatigue of the caregiver. In addition, the design of the crib may, to a certain extent, solve the pain points such as babies’ unwillingness to sleep in cribs, inconvenient use of cribs, and low usage rate of cribs.

EXPERIMENTAL

With shifting parenting attitudes and consumer behaviors among new-generation child-rearing groups, crib product demands undergo continuous transformation. The study targeted post-90s mothers and families raising infants aged 0 to 3 years, centering on mother-infant lifestyles. User behaviors obtained through preliminary non-participatory observation, user interviews, and expert interviews were summarized and deconstructed. These were analyzed via the SAPAD theoretical framework combined with Analytic Hierarchy Process (AHP) to quantify qualitative data, examine deeper meanings of mother-infant interaction behaviors across scenarios, and transform user need elements into crib design concepts. The experimental procedure is illustrated in Fig. 1.

Fig. 1. Experimental process

Behavioral Analysis of Users Based on SAPAD Model

The Semiotic Path for Product Architecture and Design is referred to as the SAPAD model, and human-computer interaction consists of the joint action of user behaviour and the product; therefore, it is also necessary to study the behavioural correlates and key correlates. User behaviours obtained through preliminary non-participatory observation, user interviews, and expert interviews were summarized and decomposed. These were constructed through the SAPAS theoretical framework combined with AHP to quantify and analyse qualitative issues, study the deeper meanings of mother-infant interaction behaviours in different scenarios, and transform the elements of user needs to the concept of baby crib design.

Behavioral Analysis of Users Based on SAPAD Model

The SAPAD model first decomposes user behaviours into tasks and subtasks. Then it maps the objects involved to corresponding behaviours to complete behaviour-product mapping (Wang 2022). Based on the SAPAD theoretical framework, analysis of interview and non-participatory observation data revealed that typical mother-infant daily activities are classifiable into five domains: (A) Sleep care, (B) Feeding, (C) Parent-child interaction, (D) Daily care, (E) Health monitoring. By systematizing relationships between infant/maternal behaviours, environments, tasks, subtasks, and behavioral correlates across these domains, the activities were subdivided into 53 specific sub-actions, as shown in Table 1.

According to SAPAD mapping theory, the environments involved in tasks were further correlated with corresponding objects to complete user behaviour-product mapping analysis, as shown in Table 2.

User Behaviour-Meaning Mapping Analysis

According to the SAPAD model, the mapping continuum of behavioral meanings comprised six levels: physical, discursive-constructive, semantic, experiential, discursive, and pragmatic. Through participatory observation and in-depth interviews, analysis of the 53 subtasks revealed that mother’s daily caring constitutes multi-product, multi-user collaborative behavior. Consequently, user behaviors were categorized into three meaning levels: experiential, semantic, and pragmatic. The experiential level emphasizes skills and sensory experiences during human-product interaction (Lu et al. 2023); the semantic level denotes meanings conveyed by mother-infant-product interactions, encompassing affective experiences; and the pragmatic level focuses on user-stakeholder interactions and information dissemination behaviors (Wang 2018).

After analyzing the detailed table derived from the interpretation of user behaviors, the volume of information was found to be relatively large and disorganized for the purpose of subsequent product construction. Therefore, the mothers’ daily infant care behaviors were screened and deduplicated, and those with higher relevance to crib-related behaviors were selected. These preliminarily screened behaviors were then interpreted using the expert evaluation method. Experienced product designers and graduate students majoring in industrial design were invited to interpret the user behaviors. The infant care behaviors were subsequently simplified and clustered to derive the core meanings, thereby completing the construction of the final meaning framework. After having achieved an in-depth understanding of the meaning of each level, the mapping relationship between the mother’s daily baby care behaviors and the meaning obtained by simplifying the content of each level corresponding to each behavior is shown in Table 3.

Table 1. Decomposition and Coding of Mother-Infant Behaviour

Table 2. User Behavior-Product Mapping Analysis

Table 3. Mother’s Daily Care of Infant Behavior and Meaning Mapping Relationship

User Requirement Element Extraction and Cluster Analysis

The meanings of maternal daily infant care behaviors have been clarified at experiential, semantic, and pragmatic levels. To further explore relationships between mothers-cribs, babies-cribs, and mothers-babies, correlations between meanings were analyzed using Boolean logic algorithms. These algorithms clustered meanings in a hierarchical manner (experiential → semantic → pragmatic), merging strongly correlated same-level meanings to identify behavioral correlations and tendencies. For clear visualization of meaning clusters, a four-color gradient scheme (light-to-dark) was implemented with numerical tiers: 3=strong correlation, 2= moderate correlation, 1=weak correlation, 0=no correlation. The output generated symmetric clustering matrices (Yang and He 2023).

The experiential level reflects users’ cognition of products or environments through prior experience, embodying human-artifact relationships. Cluster analysis identified five meaning clusters for maternal infant care behaviors at this level (Fig. 2): (1) Operational Convenience: Simplified storage steps, Non-flattening strollers, Crib bending posture, Dual-side rail installation, Toy-assisted training; (2) Standard Soothing Protocol: Embrace comforting, White noise emission, Stroller rocking, Sleep transition assistance; (3) Safety Assurance: Roll impact protection, Blanket adjustment, Prompt infant response; (4) Functional Manipulability: Headrest sleep-position adjustment, 15° incline anti-aspiration, Nightlight tactile activation, Sunlight exposure avoidance; and (5) Developmental Routine: Scheduled feeding, Diaper humidity checks, Temperature measurement, Weather-adaptive dressing, Biometric tracking, Growth data analysis.

Fig. 2. Empirical layer clustering analysis

The semantic level emphasizes meanings conveyed through mother-infant-product interactions, encompassing users’ emotional experiences. Its meaning clusters represent emotional demands toward interactive products. Cluster analysis yielded five semantic-level meaning clusters for maternal care behaviors (Fig. 3): (1) Safety Anxiety: Sleep temperature concerns, Injury prevention, Fall risk vigilance, Sleep safety prioritization, Aspiration prevention; (2) Developmental Wellness: Illness prevention, Hygiene maintenance, Healthy growth promotion, Nutritional balance; (3) Soothing Impatience: Protracted soothing duration, Repetitive motion fatigue, Personal time deprivation, Physical strain during repositioning, Arm fatigue from holding; (4) Caregiver Exhaustion: Nighttime accessibility issues, Frequent waking fatigue, Time-intensive documentation, Laborious sleep positioning, Cumbersome light-blocking procedures; and (5) Bonding Enjoyment: Positive interaction, Auditory engagement, Affectionate nurturing.

Fig. 3. Semantic layer clustering analysis

The pragmatic level emphasizes meanings conveyed through mother-infant-product interactions, encompassing users’ emotional experiences. Its meaning clusters represent personal emotional demands toward interactive products. Cluster analysis yielded five semantic-level meaning clusters for maternal care behaviors (Fig. 4): (1) Safety Concerns: Sleep temperature monitoring, Injury prevention, Fall risk vigilance, Sleep safety prioritization, Aspiration prevention; (2) Growth Wellness: Illness prevention, Hygiene maintenance, Healthy development, Nutritional balance; (3) Soothing Frustration: Protracted soothing duration, Repetitive motion fatigue, Personal time deprivation, Laborious repositioning, Arm strain from holding; (4) Caregiver Burden: Nighttime accessibility challenges, Frequent waking exhaustion, Time-intensive documentation, Laborious sleep positioning, Cumbersome light-blocking procedures; and (5) Bonding Positivity: Enjoyable interaction, Auditory engagement through music, Affectionate nurturing.

Fig. 4. Pragmatic layer clustering analysis

AHP-Based Cluster Analysis of the Core Meaning of Baby-Care Behaviour

Through Boolean logic correlation matrix analysis, meaning clusters of mothers’ baby-care behaviors were obtained across experiential, semantic, and pragmatic levels. To derive core meaning clusters, this study employed Analytic Hierarchy Process (AHP) for weight analysis of clustered meanings. Meaning clusters and their constituent meanings were designated as criterion and sub-criterion layers respectively. Weight analysis identified higher-weighted indicators as core meaning clusters within each semantic level.

Cluster Analysis of Core Meaning at the Empirical Level

Using experiential-level maternal care behavior meanings as the target layer, a hierarchical structure model was established with the five meaning clusters derived from cluster analysis serving as the criterion layer, as shown in Fig. 5.

For the established hierarchical structure model, 10 product designers, 15 crib users, and 5 infant growth experts were recruited through expert evaluation methods to form a 30-member assessment team. Using the 1-9 scale method, pairwise comparisons were performed for the five criterion layer indicators, assigning importance values to construct the judgment matrix (Table 4). The criterion layer judgment matrix underwent normalization via the sum-and-product method, yielding weight values for these indicators (Table 5).

Fig. 5. Hierarchical model of empirical layer

Table 4. The Criterion Layer Judgment Matrix

Table 5. The Criterion Layer Index Weight

The consistency test index CR was calculated as 0.089. With CR < 0.1, the judgment matrix meets validity criteria, confirming high result confidence (Table 6).

Table 6. Summary of the Consistency Test Results

Table 7. Summary of the Results of the Guideline Layer Consistency Test

Similarly, weight analysis was conducted for each sub-criterion layer factor. All judgment matrices demonstrated consistency test indices (CR) below 0.1, confirming indicator layer consistency validation as shown in Table 7. To enable unified comparison of specific indicators during subsequent crib design practices—clarifying primary-secondary relationships and facilitating targeted solution evaluation—composite weights were calculated across sub-criterion layers. The criterion layer weights were multiplied by corresponding sub-criterion weights to derive composite weight values. Experiential-level maternal care behavior weights are presented in Table 8.

Table 8. The Empirical Layer Behavioral Meaning Weight

Analysis of experiential-level maternal care behavior weights revealed that the Safety Criterion held the highest weight value, followed by Operational Convenience and Functional Manipulability. Consequently, three core meaning clusters emerged: Safety, Operational Convenience, and Functional Manipulability. Product design solutions must prioritize these requirements.

Cluster Analysis of Core Meaning at the Empirical Level

Applying the core meaning cluster analysis methodology from the experiential level to semantic and pragmatic levels yielded the semantic-level hierarchical structure model (Fig. 6) and behavior weights (Table 9). All criterion layer CR values passed consistency validation (CR < 0.1), confirming result validity (Table 10).

Table 9. The Semantic Layer Behavioral Meaning Weight

Weight analysis was conducted for pragmatic-level meanings, constructing hierarchical structure models and judgment matrices. The pragmatic-level hierarchical structure model is shown in Fig. 7, with corresponding maternal care behavior weights presented in Table 10. All criterion layer CR values passed consistency validation (CR < 0.1), confirming result validity.

Fig. 6. Hierarchical model of semantic layer

Fig. 7. Hierarchical model of pragmatic layer

Table 10. The Pragmatic Layer Behavioral Meaning Weight

RESULTS AND DISCUSSION

Module Construction and Design Element Translation for Baby Crib Products Based on Meaning Models

Previous research has completed mother-infant care behavior-to-artifact mappings, behavior-to-meaning mappings, and core meaning cluster extraction, yielding experiential-level core clusters (safety, operational convenience, functional manipulability), semantic-level core clusters (soothing Frustration, growth wellness, bonding positivity), and pragmatic-level core clusters (safety assurance, intelligent monitoring & alerts, health management systems). Identical meanings may manifest across different behaviors, while singular behaviors may embody multiple meanings, necessitating extraction of meaning commonalities and analysis of meaning correlations to construct core cluster relationships. By examining interconnections among pragmatic-, experiential-, and semantic-level core clusters, a meaning model for maternal daily care behaviors was established as shown in Fig. 8.

Through the “meaning-based product construction” framework within the SAPAD model, a re-mapping analysis of “core meaning clusters to products” was conducted to identify key artifacts corresponding to behaviors, ultimately yielding the mapped relationships among core meaning clusters, key behaviors, key artifacts, and design elements as presented in Table 11.

Fig. 8. Meaning model of mother’s daily care of baby behavior

Table 11. Mapping Analysis of the Core Significance Cluster-Object-Design Elements of the Crib

The pragmatic level maps users’ functional expectations for baby cribs, necessitating ensured usability; the experiential level maps operational requirements, demanding optimized ease-of-use and operational efficiency; the semantic level maps interactive experiences, requiring positive emotional feedback and enhanced user satisfaction during operation.

By contextualising the product design, the cluster reinterpreted the core meanings of a mother’s daily behaviour in caring for her baby using baby bedding products. Six core clusters were translated into product modules, yielding five redesigned modules centered on semantic-experiential-pragmatic integration: Intelligent Sleep Module, Safety & Monitoring Module, Health Management Module, Interactive Experience Module, and Growth Adaptation Module (Fig. 9). Corresponding crib design elements are shown in Fig. 10, with primary design directions including:

(1) Intelligent Sleep Module: Rocking mechanism, audio playback, and light control for sleep environment optimization; structural envelopment for infant security.

(2) Safety & Monitoring Module: Structural/material safety protocols, real-time surveillance, anomaly alerts, and posture-adjusting supports for aspiration prevention.

(3) Health Management Module: Vital sign monitoring (heart rate/temperature), growth tracking (height/weight), sleep quality analysis, data feedback systems, and routine development (feeding/diapering/sleep).

(4) Interactive Experience Module: Voice interaction, play activities, mobile-integrated remote operation, aesthetic formgiving, and nighttime accessibility.

(5) Growth Adaptation Module: Adjustable configurations, modular disassembly, and compact storage.

Fig. 9. Crib product module construction

Discussion

This experimental employed in-depth interviews and non-participatory observation to investigate maternal-infant lifestyles, delineating contemporary parenting patterns while summarizing characteristic caregiving activities and behaviors. Subsequent application of the SAPAD methodology facilitated behavioral meaning construction and mapping analysis, beginning with artifact-behavior mapping of caregiving objects. Meanings underlying experiential, semantic, and constructive-level behaviors were extracted, simplified, and clustered to derive meaning clusters. Quantitative weight analysis via Analytic Hierarchy Process (AHP) identified core meaning clusters, establishing behavior-core cluster mappings. This completed the behavior-meaning-artifact mapping chain, enabling product module construction and design element translation to propose concrete design directions, thereby establishing the foundation for SAPAD-based crib design strategies.

Crib design solution

Synthesizing the preceding research, the subsequent crib design focus can be definitively established. This enables analysis of design positioning and formulation of design strategies to derive the final solution, followed by feasibility verification to confirm result achievability. Guided by experimentally derived design positioning, subsequent design practices proceed with precision. The crib design framework now possesses defined parameters, serving as the basis for generating the design solution shown in Fig. 11.

Fig. 10. Crib product module construction and design element transformation

Fig. 11. Crib design solutions

This solution demonstrates the convenient feature of being able to join adult beds, thus facilitating the care of infants at night. The open design of both sides and the use of electrochromic glass at the top make the overall structure visually simpler and lighter, enhancing the interactivity of the crib. The overall shape of the crib adopts a womb-like fully-enclosed structure, giving the baby a full sense of security and wrapping, and at the same time creating a dim sleeping environment to improve sleep quality; the top is made of electrochromic glass, which can adjust the transparency according to the time change to create a suitable sleeping atmosphere for the baby. The crib is equipped with an intelligent monitoring system, including a high-definition camera and abnormal situation reminder function, which can monitor the baby’s dynamics in real time and send reminders to parents in time. The mattress is equipped with intelligent adjusting function, which can automatically adjust the angle according to the baby’s sleep state, preventing problems such as choking and head deviation. In addition, it is equipped with intelligent functions such as rocking and soothing, music playback, voice interaction, etc. These functions can help the baby fall asleep quickly. In terms of design details, the crib enclosure adopts a removable fence design, which is convenient for splicing with a queen-size bed and ensures the convenience of night care; the nappy storage space is integrated at the end of the bed for invisible storage to meet the usage habits of parents. The overall design not only focuses on the functionality of the product, but it also takes into account the aesthetics and humanisation, aiming to provide a safe, comfortable and intelligent sleeping environment for mothers and babies.

User experience evaluation of crib design solutions

The fuzzy comprehensive evaluation method utilizes fuzzy mathematics as its foundation, applying fuzzy relation synthesis principles to quantify ambiguously bounded factors and conduct multidimensional assessment of evaluated subjects. The operational procedure entails: establishing an evaluation index set; determining factor weights and corresponding membership vectors; constructing the fuzzy judgment matrix; and deriving comprehensive evaluation results through normalized fuzzy operations combining the matrix with factor weight vectors (Xu 2023).

Fig. 12. Plot representation of sample cases

According to the summarized characteristics of the new generation of mother and child lifestyles combined with the actual situation of the program, the following six indicators and indicator weights were set to evaluate the program: Set the evaluation indicator ensemble U = {intelligent, safe, convenient, functional, diversified, personalized}. Set the set of comments as E = {very satisfied, satisfied, average, dissatisfied, very dissatisfied}, and assign the value of each grade as E = {90, 75, 60, 50, 40}. First, the baby crib, which is currently the leading seller on the Tmall platform, was selected as a sample case and used as a reference for the final design. As shown in Fig. 12, the crib has outstanding performance in the market, and its practicality and value are widely recognized.

Through comparative evaluation and analysis, it can effectively test whether the designed solution can meet the actual needs of users. A total of 20 evaluators, including children’s product designers, actual users of the crib, and infant growth experts, were invited to professionally evaluate the design solutions of the crib and the selected sample cases.

The weight of each factor was determined by conducting questionnaire research on the evaluation team, referring to the 1 to 9 importance judgement scale table for evaluation, and obtaining the weight coefficients of each indicator, as shown in Table 12, and passing the consistency test, as shown in Table 13.

Constructing a fuzzy comprehensive evaluation matrix: A comprehensive evaluation and analysis of the final design scheme and sample case were conducted by the evaluation team, and the data were normalized such that the sum of each row of the matrix is 1 (Wang et al. 2021), and a fuzzy comprehensive evaluation matrix R is obtained:

Fuzzy composite judgments, matrix synthesis operations, and normalization were performed to obtain fuzzy composite evaluation vectors for each of the 2:

M1=A×D=（0.339，0.393，0.235，0.033，0.000）

M2=A×D=（0.499，0.368，0.129，0.004，0.000）

Combined with the weighted calculation of the comment set scores, the overall score of the selected crib sample case was 75.73, and the overall score of the final design solution was 80.45. This resulted in the user satisfaction level of both crib designs being “satisfied”, and the final crib design solution was significantly better than the sample case. Thus, the crib design as a whole met the needs and preferences of users, especially in terms of intelligent operation, safety, functionality, and personalization of shape. This means that the crib design as a whole met the users’ needs and preferences, especially in terms of intelligent operation, safety, functionality and personalised shape. However, there were still deficiencies in some details, mainly in the design of convenience, such as flexible movement and nappy storage, which need to be improved in the later design.

Table 12. Each Indicator and Indicator Rights Recapture Table

Table 13. Results of the Consistency Test

CONCLUSIONS

1. This study integrates the semiotics approach of product architecture design (SAPAD) model with the Analytic Hierarchy Process (AHP) to identify user needs and design pain points for infant cribs within mother-infant populations. As a multi-user product, this methodology resolves the challenges of disorganized research data and ambiguous priorities inherent in multi-user studies, providing a scientific framework that delivers clear design guidelines and facilitates the clarification of design rationale.
2. This study adopted maternal-infant lifestyles as its research lens, conducting field research supplemented by literature analysis to examine maternal care behaviors. Through the SAPAD methodological framework, it established behavior–meaning–artifact mapping relationships. This approach thus established a transformative pathway from user insights to design priorities.
3. Building upon this foundation, design implementation and evaluation were conducted to scientifically develop solutions that provide detailed caregiving conditions. These addressed infant sleep challenges and alleviated the pressures of parenting. This co-design framework integrated users, experts, and designers, resolving ambiguous complexities inherent in crib design due to distinct user demographics. This further established a theoretical foundation and practical framework for future infant furniture research.

ACKNOWLEDGMENTS

Participants

This study involved human participants (children) and was conducted in accordance with the ethical principles outlined in the Declaration of Helsinki and relevant national guidelines for research involving human subjects. The research protocol was designed to ensure the protection of participants’ rights, safety, and well-being. Written informed consent was obtained from the parents or legal guardians of all participants prior to their inclusion in the study.

Ethics Statement

The authors confirm that all methods were carried out in accordance with relevant guidelines and regulations. The study was performed in accordance with the 1964 declaration of HELSINKI and later amendments. The authors confirm that all experimental protocols were approved by the Ethics Committee of Nanjing Forestry University. The informed consent was obtained from all subjects and their legal guardians. The subjects are aware of the research background, process, results, and objectives, and sign a written informed consent form.

Data Accessibility Statement

All relevant data are within the paper.

Use of Generative AI

During the preparation of this work, the authors used ChatGPT in order to improve language. After using this tool, the authors reviewed and edited the content as needed and take full responsibility for the content of the publication.

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Article submitted: September 22, 2025; Peer review completed: February 7, 2026; Revised version received: February 11, 2026; Accepted: February 12, 2026; Published: February 20, 2026.

DOI: 10.15376/biores.21.2.3369-3393