Systematic Review of Mecanum and Omni Wheel Technologies for Motor Impairments

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This is the review paper dealing with so called mecanum and omni wheel technologies  for the  motor impairments. The manuscript is commendable for its structured approach, utilizing the PRISMA method to ensure a comprehensive examination of existing literature across reputable databases. Unfortunately, this text be accepted for publication in present form and must de duly revised.

1. The discussion of limitations such as performance issues on uneven terrain and high costs is a critical inclusion that adds balance to the review. The review could benefit from more detail regarding how these limitations were assessed in the studies reviewed. A clearer connection between identified challenges and proposed recommendations would enhance the overall coherence of the submitted review.
2. The suggestions for future research are promising, particularly the call for mechanical advancements and the integration of artificial intelligence. These recommendations indicate a forward-thinking approach that could improve the functionality and accessibility. However, it would be beneficial to specify what types of mechanical advancements or AI applications are being considered, as this could provide clearer direction for future studies.
3. The mathematical challenges must be included and classified in the review.
4. Joint references like [1-20] are not allowed. Please cite each and outline its value and contribution to the state of the art.

Author Response

We sincerely thank the Reviewer for their valuable feedback, which helped us improve the clarity and overall quality of our manuscript. In response to all five reviewers comments, we have made several key revisions summarized below: 

• The abstract and introduction have been rewritten to better emphasize the study’s scope and novelty, clearly focusing on assistive technologies for individuals with motor impairments rather than general Mecanum/Omni applications. 

• We clarified the methodology by refining the inclusion/exclusion criteria and updated the PRISMA diagram. The process for resolving disagreements between reviewers was also explicitly described to improve transparency. 

• The Results section was reorganized around six core challenges: stability, control systems, energy efficiency, automation, cost, and real-world validation. This thematic structure allows for a clearer and more targeted analysis of the literature. 

• We redesigned and expanded the summary tables. Each now corresponds to a thematic area and follows a standardized format (e.g., function, construction, control methods), allowing easier cross-study comparisons. 

• We also strengthened the comparative analysis, highlighting recurring challenges and evaluating the effectiveness of proposed solutions across studies. 

• Finally, each thematic section in discussion concludes with practical recommendations for future research and development, aimed at both academic and applied contexts. 

In direct response to the detailed feedback provided by Reviewer #1: 

Reviewer Comment 1: 
“The discussion of limitations such as performance issues on uneven terrain and high costs is a critical inclusion that adds balance to the review. The review could benefit from more detail regarding how these limitations were assessed in the studies reviewed.” 

Author Response: 
Thank you for this important observation. In the revised manuscript, we have expanded the Discussion 4 and Limitations 5 (pp. 12-15)  to clarify how these limitations were assessed. Specifically, we now refer to individual studies that reported measurable outcomes such as vibration amplitude, tilt angles, energy consumption under load, and obstacle negotiation success rates. Where possible, we described the evaluation methods (e.g., simulation, real-world field trials, or quantitative measurements) to provide clearer evidence supporting the limitations discussed. 

Reviewer Comment 2: 
“A clearer connection between identified challenges and proposed recommendations would enhance the overall coherence of the submitted review.” 

Author Response: 
We appreciate this suggestion and have revised the structure of the Results and Discussion sections to ensure that each identified challenge is directly followed by specific responses and future directions. For instance, the issue of poor terrain adaptability is now immediately followed by proposed solutions, such as active suspension systems and hybrid wheel configurations. Similarly, energy inefficiency is discussed alongside control strategies like field-oriented control. This alignment enhances the logical flow between findings and recommendations. 

Reviewer Comment 3: 
“The suggestions for future research are promising, particularly the call for mechanical advancements and the integration of artificial intelligence. However, it would be beneficial to specify what types of mechanical advancements or AI applications are being considered, as this could provide clearer direction for future studies.” 

Author Response: 
Thank you for this helpful comment. We have now specified the types of mechanical and AI advancements in discussion (pp. 12-15). Mechanically, we highlight solutions such as modular drive units, adaptive suspensions, and hybrid wheel layouts for curb climbing and off-road mobility. In terms of AI, we discuss applications including SLAM-based autonomous navigation , automatic docking to care beds, AI-assisted trajectory planning, and user-intent prediction via EEG signals and Human-Centered Explainable AI. 

Reviewer Comment 4: 
“The mathematical challenges must be included and classified in the review.” 

Author Response: 
We fully agree, and this point has been addressed by adding a dedicated discussion of key mathematical and computational challenges in the Discussion section (lines 389-403). These include: 
– Kinematic modeling for omnidirectional movement and trajectory control ; 
– Nonlinear control methods such as sliding-mode control for handling wheel slip and surface variability ; 
– Field-oriented control (FOC) for improving motor efficiency and torque regulation (Clarke and Park transformations) ; 
– Biosignal processing and classification algorithms (e.g., SVM, P300) used in gesture and BCI-based systems 
By highlighting these areas, we provide a clearer picture of the modeling and algorithmic requirements needed for future system development. 

Reviewer Comment 5: 
“Joint references like [1–20] are not allowed. Please cite each and outline its value and contribution to the state of the art.” 

Response: 
This issue has been fully corrected throughout the manuscript. Each reference is now cited individually, and in all summary tables as well as in the main body of text, the specific contributions of each study are outlined.  

 

We believe these changes enhance the manuscript’s clarity, relevance, and usefulness for the field. 

Reviewer 2 Report

Comments and Suggestions for Authors

The current systematic review paper aimed to investigate the mecanum and Omni wheel-based mobility devices through the lens of the development, design, functionality, and user impact to provide more evidence about their functionality as assistive technologies for people with motor impairments.
Indeed, the topic is relevant, and it has potential for practical implications. 
The title is relevant to the objectives and clarifies the type of study.
The abstract briefly but accurately describes the main objectives, the main methods, and the key findings, as well as challenges and issues for future research.
The introduction section accurately describes Mecanum and Omni wheels and their innovative mechanisms. In lines 50-51, it is mentioned that “Beyond providing enhanced maneuverability, these devices have demonstrated potential in addressing various challenges.” It would be useful to clarify these challenges and why this study hypothesizes that they can provide solutions to specific problems related to the topic of the study.
In addition, it would be useful to more clearly state why this systematic review is needed. Explain how it will address the identified limitations or knowledge gaps. Highlight the potential value and significance of the review's findings for patients, clinicians, policymakers, or future research.
In the material and methods section, it is important to improve structure according to the PRISMA guidelines. Use different subsections to answer all the topics mentioned to the PRISMA guidelines. Specify the inclusion and exclusion criteria for the review and how studies were grouped for the syntheses. Present the full search strategies for all databases, registers, and websites, including any filters and limits used. Specify the methods used to collect data from reports, including how many reviewers collected data from each report, whether they worked independently, any processes for obtaining or confirming data from study investigators, and if applicable, details of automation tools used in the process. Specify the methods used to assess the risk of bias in the included studies, including details of the tool(s) used, how many reviewers assessed each study whether they worked independently, and if applicable, details of automation tools used in the process. 
Provide the number and the detail of the protocol used. Provide the number or the access details. In addition, describe in the paper whether you followed the initial planning of the protocol. Please submit as supplementary material the PRISMA statement.
In the results section, the table is useful. However, you must better synthesize results to answer the research questions. In addition, you must make revisions to follow all the requirements of the PRISMA statement. Relevant tables and figures would improve readability.
The discussion section makes several critical comments and interpretations. Discuss also any limitations of the review processes used.

Author Response

We sincerely thank the Reviewer for their valuable feedback, which helped us improve the clarity and overall quality of our manuscript. In response to all five reviewers comments, we have made several key revisions summarized below: 

• The abstract and introduction have been rewritten to better emphasize the study’s scope and novelty, clearly focusing on assistive technologies for individuals with motor impairments rather than general Mecanum/Omni applications. 

• We clarified the methodology by refining the inclusion/exclusion criteria and updated the PRISMA diagram. The process for resolving disagreements between reviewers was also explicitly described to improve transparency. 

• The Results section was reorganized around six core challenges: stability, control systems, energy efficiency, automation, cost, and real-world validation. This thematic structure allows for a clearer and more targeted analysis of the literature. 

• We redesigned and expanded the summary tables. Each now corresponds to a thematic area and follows a standardized format (e.g., function, construction, control methods), allowing easier cross-study comparisons. 

• We also strengthened the comparative analysis, highlighting recurring challenges and evaluating the effectiveness of proposed solutions across studies. 

• Finally, each thematic section in discussion concludes with practical recommendations for future research and development, aimed at both academic and applied contexts. 

In direct response to the detailed feedback provided by Reviewer #2: 

Comment 1: 

In lines 50–51, it is mentioned that “Beyond providing enhanced maneuverability, these devices have demonstrated potential in addressing various challenges.” It would be useful to clarify these challenges and why this study hypothesizes that they can provide solutions to specific problems related to the topic of the study. 

Response: 
We have expanded this part of the Introduction (p. 3, lines 77–85) to specify the challenges posed by traditional assistive devices—such as difficulty navigating tight indoor spaces, poor traction on uneven terrain, and limited control options for users with severe impairments—and explained how Mecanum and Omni wheels may overcome these limitations. 

Comment 2: 

It would be useful to more clearly state why this systematic review is needed. Explain how it will address the identified limitations or knowledge gaps. Highlight the potential value and significance of the review's findings for patients, clinicians, policymakers, or future research. 

Response: 
This has been clarified in the Introduction (p. 3, lines 86-96). We emphasize the novelty of the review, its practical orientation, and its intended audience—including engineers, clinicians, and policymakers. We also explicitly identify the lack of existing reviews that focus specifically on assistive mobility systems using Mecanum and Omni wheels. 

Comment 3: 

In the material and methods section, it is important to improve structure according to the PRISMA guidelines. Use different subsections... 

Response: 
We have restructured the Materials and Methods section (pp. 3–4) using clearly labeled subsections: 

• 2.1 Eligibility Criteria 

• 2.2 Information Sources and Search Strategy 

• 2.3 Selection Process 

• 2.4 Data Collection and Items 

• 2.5 Risk of Bias Assessment 

• 2.6 Synthesis Methods 

• 2.7 Reporting 

Each subsection addresses the relevant PRISMA elements. We also explicitly state the number of reviewers, independence of review, inclusion/exclusion criteria, and absence of automation tools.  

Comment 4: 

Provide the number and the detail of the protocol used. Provide the number or the access details. In addition, describe in the paper whether you followed the initial planning of the protocol. 

Response: 
Thank you for this important remark. As the protocol was not prospectively registered, we have clarified this in Section 2 of the manuscript. It was not registered in PROSPERO because it does not meet the eligibility criteria for inclusion. PROSPERO includes two registries: the original registry, which covers systematic reviews of studies involving human participants and directly related to human health, and PROSPERO 4 Animals, which includes systematic reviews of animal studies related to human health. Since the present review focuses primarily on technological developments in assistive mobility devices rather than direct clinical outcomes or interventions involving human or animal participants, it falls outside the scope of both PROSPERO registries. 

Nonetheless, the review was conducted in full accordance with the PRISMA guidelines, and the methodology—including the search strategy, eligibility criteria, and data synthesis plan—was predefined before the literature search began. 

Comment 5: 

In the results section, the table is useful. However, you must better synthesize results to answer the research questions. In addition, you must make revisions to follow all the requirements of the PRISMA statement. Relevant tables and figures would improve readability. 

Response: 
We have revised the Results section (pp. 5–12) to include six thematic categories: 

3.1 Stability and Terrain Adaptation 

3.2 Control Systems and User Interfaces 

3.3 Energy Efficiency and Drive Systems 

3.4 Automation and System Intelligence 

3.5 Cost and Accessibility 

3.6 Validation and Real-World Testing 

Each subsection includes a summary table with unified columns, and we explicitly state how each study contributes to addressing specific challenges.  

Comment 6: 

The discussion section makes several critical comments and interpretations. Discuss also any limitations of the review processes used. 

Response: 
We have added a paragraph in Section 5 (Limitations, pp. 16) discussing methodological limitations, such as the exclusion of grey literature, lack of protocol registration, and the subjective nature of qualitative synthesis due to heterogeneity of studies. We also emphasize the need for standardized validation in future research. 

 

We hope that the revisions sufficiently address all the Reviewer’s concerns and improve the clarity, completeness, and scientific value of the paper. 

Reviewer 3 Report

Comments and Suggestions for Authors

 

Dear authors,

Thank you for submitting your research work to our journal. This manuscript provides a systematic review of Mecanum and Omni wheel technologies for motor impairments. The manuscript is interesting. However, its quality still needs to be improved before publication.

1. The abstract can be improved. The current abstract lacks publishing value and has poor logic. The publication of papers is born to address challenges, including articles and reviews. As a review, it should focus on the challenges and trends in relevant fields for reference by international peers. Authors can refer to relevant reviews, many of which are titled 'Challenges and Trends'. It is recommended that authors reorganize the abstract to list the challenges and trends identified as thoroughly as possible.
2. The introduction can be improved. The introduction also has similar issues to the abstract, and the six bullet questions at the end of the introduction are inconsistent with the abstract. Authors should extract three to four findings as contributions, including challenges and trends. Meanwhile, maintain consistency with the abstract content. Finally, use a paragraph to introduce the organizational structure of the entire text.
3. Chapter 2 can be improved. As a review, 47 references are insufficient. Authors can reorganize references around challenges and trends in related fields, focusing on new discoveries and directions, which can help enhance the publication value and attention of this manuscript.
4. Chapters 3 can be improved. Chapter 3 is an excessively long chapter with a lengthy table that lacks both logic and readability. It is recommended to reorganize the content around different challenge themes and establish several sub chapters, each with its own logical findings. Correspondingly, a large table can be divided into multiple tables based on different challenges and topics.
5. Chapters 4 can be improved. Chapter 4 is also an excessively long chapter that can be confusing to read. It is recommended to split it into several sub chapters and discuss different challenges separately.
6. Chapters 5 can be improved. The conclusion should summarize the contributions and findings of the entire manuscript, and indicate the shortcomings and next research directions of this manuscript.
7. The references can be improved. I hope to increase more relevant SOTA research work.

Author Response

We sincerely thank the Reviewer for their valuable feedback, which helped us improve the clarity and overall quality of our manuscript. In response to all five reviewers comments, we have made several key revisions summarized below: 

• The abstract and introduction have been rewritten to better emphasize the study’s scope and novelty, clearly focusing on assistive technologies for individuals with motor impairments rather than general Mecanum/Omni applications. 

• We clarified the methodology by refining the inclusion/exclusion criteria and updated the PRISMA diagram. The process for resolving disagreements between reviewers was also explicitly described to improve transparency. 

• The Results section was reorganized around six core challenges: stability, control systems, energy efficiency, automation, cost, and real-world validation. This thematic structure allows for a clearer and more targeted analysis of the literature. 

• We redesigned and expanded the summary tables. Each now corresponds to a thematic area and follows a standardized format (e.g., function, construction, control methods), allowing easier cross-study comparisons. 

• We also strengthened the comparative analysis, highlighting recurring challenges and evaluating the effectiveness of proposed solutions across studies. 

• Finally, each thematic section in discussion concludes with practical recommendations for future research and development, aimed at both academic and applied contexts. 

In direct response to the detailed feedback provided by Reviewer #3: 

 

Comment 1: 
“The abstract can be improved… reorganize the abstract to list the challenges and trends identified as thoroughly as possible.” 

Response: 
The abstract has been completely revised  to improve its logical flow and highlight key challenges (e.g., terrain instability, complex control, energy demand, high cost) and emerging trends (e.g., AI-assisted autonomy, multimodal interfaces, modular construction). It now better aligns with standard formats seen in reviews titled "Challenges and Trends". 

Comment 2: 
“The introduction can be improved… Authors should extract three to four findings as contributions, including challenges and trends. Maintain consistency with the abstract content.” 

Response: 
The Introduction has been restructured. The key contributions of this review are as follows: 

(1) It identifies and categorizes the main mechanical, control-related, and usability challenges associated with Mecanum and Omni wheel-based assistive mobility systems; 

(2) It highlights recent trends in design and interaction technologies, including AI-driven navigation, multimodal user input, and adaptive mechanical configurations; 

(3) It provides strategic recommendations for future research aimed at improving terrain adaptability, user accessibility, and system affordability. 

 

Comment 3: 
“Chapter 2 can be improved… 47 references are insufficient… focus on new discoveries and directions.” 

Response: 
We expanded the literature coverage to 57 references, including more recent and domain-specific studies published in 2022–2024 (e.g., [48], [50], [56], [57]). In discussion references were thematically linked to emerging research challenges and reformulated to emphasize trends and gaps. 

Comment 4: 
“Chapter 3 is excessively long… reorganize around different challenge themes… divide the large table into multiple ones.” 

Response: 
Chapter 3 (Results) was reorganized into six thematic subchapters: 

3.1 Stability and Terrain Adaptation 

3.2 Control Systems and User Interfaces 

3.3 Energy Efficiency and Drive Systems 

3.4 Automation and System Intelligence 

3.5 Cost and Accessibility 

3.6 Validation and Real-World Testing 

Each subsection contains its own dedicated table to improve readability and logical coherence (Tables 1–6). 

Comment 5: 
“Chapter 4 is also excessively long… split into several sub chapters and discuss different challenges separately.” 

Response: 
Chapter 4 (Discussion) was revised into structured subsections addressing each of the six main challenges (pp. 23–29). This new format enhances focus, allows clearer linkage with Section 3, and avoids redundancy. Each subsection presents trends, limitations, and examples, followed by strategic recommendations. 

Comment 6: 
“Chapter 5 can be improved. The conclusion should summarize contributions and indicate shortcomings and next directions.” 

Response: 
Chapter 5 Limitations of the Review Process was added (Conclusion, p. 30). Chapter 6. Conclusions now summarize contributions and indicate shortcomings and next directions. 

Comment 7: 
“The references can be improved… increase more relevant SOTA research work.” 

Response: 
We enriched the reference list with state-of-the-art (SOTA) publications, particularly from 2020–2024, in areas such as smart healthcare, IoT integration, and machine learning in assistive mobility (e.g., refs [50], [56], [57]). The reference section now includes 57 entries, covering engineering, clinical relevance, and real-world deployment. 

 

We believe the manuscript has been significantly improved in response to your insightful suggestions and hope it now meets the standard for publication. We are grateful for your time and consideration. 

Reviewer 4 Report

Comments and Suggestions for Authors

This manuscript presents a systematic review of Mecanum and Omni wheel technologies in assistive mobility devices for individuals with motor impairments. The authors have compiled a substantial body of literature, identifying 26 relevant papers from an initial pool of 968 references. The review examines mechanical design, control systems, usability considerations, and future research directions. The comprehensive table summarizing the included studies provides a valuable resource for researchers in this field. However, several substantive issues need to be addressed before this manuscript is suitable for publication.

1. While the PRISMA methodology is mentioned, the search strategy lacks sufficient detail. The authors should clarify their inclusion/exclusion criteria beyond what's presented in Figure 2, and explain how quality assessment of included studies was performed.
2. The review primarily summarizes existing work rather than critically analyzing its limitations. For instance, most studies appear to be laboratory-based with small sample sizes, yet the implications of this for real-world application aren't adequately addressed.
3. There’s minimal discussion of user acceptance studies, quality of life impacts, or participatory design approaches. Given that these technologies aim to serve people with disabilities, this omission significantly weakens the review.
4. There’s considerable overlap between the Results and Discussion sections, with similar content on terrain adaptability, control systems, and energy efficiency appearing in both sections.
5. The review presents multiple implementations but lacks systematic comparison between different approaches. Authors should propose a structured framework comparing performance metrics (maneuverability, stability, energy efficiency, cost) across different designs.
6. Some technologies (particularly MEBot) receive disproportionate attention while others are only briefly described. This imbalance raises questions about selection bias in the presentation of findings.
7. Cost remains a significant barrier to adoption of advanced wheelchair technologies, yet economic analyses are largely absent from the review.
8. Table 1’s current format creates readability challenges. The excessive text in each cell makes it difficult to quickly extract key information. Consider restructuring this table using a more standardized approach with consistent subcategories and quantifiable metrics where possible.
9. The PRISMA diagram (Figure 2) requires substantial improvement.  The reasons for exclusion listed in the right-side box lack specificity and methodological rigor. Terms like “Omni platform without application for people with motor impairments”are ambiguous and don't clearly communicate the exclusion criteria.

 

Author Response

We sincerely thank the Reviewer for their valuable feedback, which helped us improve the clarity and overall quality of our manuscript. In response to all five reviewers comments, we have made several key revisions summarized below: 

• The abstract and introduction have been rewritten to better emphasize the study’s scope and novelty, clearly focusing on assistive technologies for individuals with motor impairments rather than general Mecanum/Omni applications. 

• We clarified the methodology by refining the inclusion/exclusion criteria and updated the PRISMA diagram. The process for resolving disagreements between reviewers was also explicitly described to improve transparency. 

• The Results section was reorganized around six core challenges: stability, control systems, energy efficiency, automation, cost, and real-world validation. This thematic structure allows for a clearer and more targeted analysis of the literature. 

• We redesigned and expanded the summary tables. Each now corresponds to a thematic area and follows a standardized format (e.g., function, construction, control methods), allowing easier cross-study comparisons. 

• We also strengthened the comparative analysis, highlighting recurring challenges and evaluating the effectiveness of proposed solutions across studies. 

• Finally, each thematic section in discussion concludes with practical recommendations for future research and development, aimed at both academic and applied contexts. 

In direct response to the detailed feedback provided by Reviewer #4: 

Comment: 
1.The authors should clarify their inclusion/exclusion criteria beyond what's presented in Figure 2, and explain how quality assessment of included studies was performed. 

Response: 
We have significantly expanded Section 2.1 (Eligibility Criteria, p. 3) and Section 2.3 (Selection Process, pp. 4–5) to provide detailed and specific inclusion and exclusion criteria. The right-hand box of the PRISMA diagram (Figure 2, p. 5) has been updated to reflect clear, specific exclusion reasons. Additionally, Section 2.5 (Risk of Bias Assessment, p.4) now describes our quality assessment strategy based on implementation status, reporting transparency, and stated limitations. 

Comment: 
2.The review primarily summarizes existing work rather than critically analyzing its limitations. For instance, most studies appear to be laboratory-based with small sample sizes, yet the implications of this for real-world application aren't adequately addressed.  

Response: 
We have addressed this by strengthening the Discussion (Section 4, pp. 12-15), especially the first paragraph of each thematic subsection (e.g., Stability, Control Systems). We highlight small sample sizes, controlled-lab biases, and lack of long-term testing. Real-world validation challenges are also emphasized. 

Comment: 

3. There’s minimal discussion of user acceptance studies, quality of life impacts, or participatory design approaches. Given that these technologies aim to serve people with disabilities, this omission significantly weakens the review.

Response: 

We added new content in discussion (lines 451-469) explicitly discussing the absence of user-centered evaluations and participatory design.  

Comment: 

4.There’s considerable overlap between the Results and Discussion sections, with similar content on terrain adaptability, control systems, and energy efficiency appearing in both sections. 

Response: 

The Results now strictly focus on study summaries and factual extraction. Interpretations, limitations, and future implications have been moved to the Discussion. Repetitive phrasing has been eliminated. 

Comment: 

5.The review presents multiple implementations but lacks systematic comparison between different approaches. Authors should propose a structured framework comparing performance metrics (maneuverability, stability, energy efficiency, cost) across different designs. 

Response: 
We revised Results and balanced the presentation by summarizing all systems more evenly.  

Comment: 

6.Some technologies (particularly MEBot) receive disproportionate attention while others are only briefly described. This imbalance raises questions about selection bias in the presentation of findings. 

Response: 

Content on MEBot has been shortened, and less-covered systems like [34], [35], and [43] are now expanded. We continued this approach in each section. 

Comment: 

7.Cost remains a significant barrier to adoption of advanced wheelchair technologies, yet economic analyses are largely absent from the review. 

Response: 

Section 3.5 and Discussion (lines 470-479) subsection now include a deeper discussion of affordability strategies, including open-source solutions, modular designs, and cost-performance tradeoffs. We also added references [51], [43], and [48] for context. 

Comment: 

8.Table 1’s current format creates readability challenges. The excessive text in each cell makes it difficult to quickly extract key information. Consider restructuring this table using a more standardized approach with consistent subcategories and quantifiable metrics where possible. 

Response: 

As mentioned earlier we redesigned and expanded the summary tables. Each now corresponds to a thematic area and follows a standardized format (e.g., function, construction, control methods), allowing easier cross-study comparisons. 

Comment: 

9.The PRISMA diagram (Figure 2) requires substantial improvement.  The reasons for exclusion listed in the right-side box lack specificity and methodological rigor. Terms like “Omni platform without application for people with motor impairments”are ambiguous and don't clearly communicate the exclusion criteria. 

Response: 

We revised Figure 2  with clearer exclusion reasons (e.g., “no application for motor impairments”, “non-functional prototypes”) and provided additional methodological clarification in Section 2.3. Selection Process. 

 

We hope the revised manuscript meets expectations and is now suitable for publication. 

Reviewer 5 Report

Comments and Suggestions for Authors

The presented manuscript is structured as a systematic review. It is focused on an interesting – practical insights to assist designers of mobility platforms for individuals with motor impairments in addressing key trend and challenges.

The manuscript is well designed. It includes an introduction to the problem, which offers a strong background of the solved problem. The section Materials and methods is shorter, at which, the authors present the main published research focused on the same or rather similar stud. The results of the research are formatted in the text together with a table. Further, a Discussion follows. There, the authors present and the main findings of the research and a comparison with the previous studies. Finally, there is written Conclusions.

In my opinion, the manuscript is well designed and it can be published in the present form.

Author Response

We sincerely thank the Reviewer for their positive and encouraging feedback. We appreciate your recognition of the manuscript’s structure, clarity, and practical relevance for the development of mobility platforms for individuals with motor impairments. 

Although no major changes were requested in your review, we have made several improvements to the manuscript in response to the suggestions from other reviewers. These include:  

• Refining the abstract and introduction to better highlight the novelty and scope of the study; 

• Clarifying the methodology, including updated inclusion criteria and PRISMA documentation; 

• Reorganizing the Results section around six thematic challenges to improve focus and readability; 

• Expanding and standardizing comparison tables for easier interpretation; 

• Strengthening the comparative analysis and adding targeted recommendations for future research. 

We are grateful for your support and pleased that the revised version meets the expectations for publication. 

 

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript was revised. The concluding remarks are still shallow and must be duly improved. I also believe authors should add more systematic analysis of the mathematical challenges 

Author Response

Dear Reviewer,

The revised version of the manuscript introduces substantial improvements based on reviewers' feedback. The main differences compared to the earlier version include:

• Sections 3 and 4 were thoroughly reorganized to avoid repeated descriptions. The Results section now strictly presents factual content from the reviewed studies, while the Discussion focuses on interpretation, cross-comparison, and implications for future work.
• The Discussion section has been significantly expanded to address the limited ecological validity of many studies. Specific paragraphs now explore how the absence of diverse user testing and real-world environments impacts generalizability and future design needs.
• The revised version explicitly states that no formal bias or scoring framework was applied due to the engineering nature of included studies. Sources of bias are now acknowledged directly in Section 2.5.
• The PRISMA flowchart and Section 2.1 were updated to provide clear and specific exclusion reasons, replacing ambiguous phrasing like "not intended for individuals with disabilities" with "No working prototype with Mecanum/Omni wheels" or "Study does not include people with motor impairments."
• Supplementary comparison table:
  A new Supplementary Table was added to support cross-study comparison using standardized performance parameters, including:
  Wheel type, Vibration reduction (%), Obstacle climbing height (mm), Battery type, Motor type / power, Cost strategy.
  This table allows readers to better understand key technical trade-offs between Mecanum and Omni systems. A reference to the supplementary table was added to the Data Availability Statement.
• Expanded reference base:
  Several new studies were added to ensure up-to-date coverage and meet the recommendation of including at least 60 references.

In direct response to the detailed feedback provided by Reviewer #1:

Reviewer comment:

The manuscript was revised. The concluding remarks are still shallow and must be duly improved. I also believe authors should add more systematic analysis of the mathematical challenges.

Author response:

We thank the reviewer for this valuable feedback.

To address this, we made the following substantial improvements in the revised manuscript:

1. The conclusion section (pp.17-18) has been thoroughly revised to offer more than a summary. It now emphasizes not only the practical implications of the reviewed technologies but also outlines precise and actionable research directions. This includes calls for interdisciplinary collaboration, improved ergonomic integration, user-centered design principles, and transparency in algorithmic development.
2. We have introduced a new subsection (4.1) titled "Mathematical and Computational Challenges in Assistive Mobility Systems" (p.16). This section presents a more systematic discussion of the analytical and algorithmic issues involved in modeling, control, and signal processing. We cover:
• Field-Oriented Control (FOC) and its real-time transformation requirements;
• Sliding Mode Control (SMC) and the stability challenges due to discontinuities;
• Kinematic optimization and velocity mapping for Mecanum platforms;
• Signal processing and classification pipelines required in biosignal-based systems (e.g., EMG, BCI);
• Recent examples from the literature that demonstrate modeling and computational trade-offs. [59-60]

These updates aim to highlight that beyond hardware innovation, mathematical modeling and algorithm design are critical areas that deserve more attention in assistive robotics research. This systematic addition complements the design- and usability-focused parts of the review.

 

 

Reviewer 2 Report

Comments and Suggestions for Authors

Dear authors,

I would like to thank you for your response. 

I have read the revised manuscript. I believe that you have addressed my concerns.

Kind regards

Author Response

Dear Reviewer,

Thank you very much for your kind follow-up and for taking the time to carefully review the revised manuscript.

We are pleased to hear that the changes addressed your concerns. As a brief summary, the following improvements were made in latest version of manuscript:

• The Discussion section was expanded to more deeply analyze the limitations of the reviewed studies, particularly the lack of real-world testing and the restricted diversity of test users.
• We added a dedicated subsection addressing the gap between lab-based validation and ecological applicability, with specific examples and implications for future work.
• The Conclusion was revised to be more comprehensive, highlighting practical recommendations and future research priorities.
• A new subsection (4.1) was included to more systematically discuss the mathematical and computational challenges, including control strategies, modeling, and signal processing issues.
• The overall structure of Sections 3 and 4 was revised to avoid redundancy and clarify the distinction between reporting and interpretation.

We sincerely appreciate your constructive input, which significantly helped improve the quality and clarity of the paper.

Reviewer 3 Report

Comments and Suggestions for Authors

Dear authors,

Thank you for carefully revising the manuscript and responding to the review comments one by one. The quality of the manuscript has significantly improved compared to the original version. However, there are still the following modification suggestions.

1. The items in Tables 5 and 6 are relatively few, with only 1-2 rows. It is recommended to increase them to at least 3 rows, allowing for references that have appeared in the previous tables.
2. It is recommended to add at least 3 more references, for a total of 60 or more.

Author Response

Dear Reviewer,

The revised version of the manuscript introduces substantial improvements based on reviewers' feedback. The main differences compared to the earlier version include:

• Sections 3 and 4 were thoroughly reorganized to avoid repeated descriptions. The Results section now strictly presents factual content from the reviewed studies, while the Discussion focuses on interpretation, cross-comparison, and implications for future work.
• The Discussion section has been significantly expanded to address the limited ecological validity of many studies. Specific paragraphs now explore how the absence of diverse user testing and real-world environments impacts generalizability and future design needs.
• The revised version explicitly states that no formal bias or scoring framework was applied due to the engineering nature of included studies. Sources of bias (e.g., small samples, limited environments) are now acknowledged directly in Section 2.5.
• The PRISMA flowchart and Section 2.1 were updated to provide clear and specific exclusion reasons, replacing ambiguous phrasing like "not intended for individuals with disabilities" with "No working prototype with Mecanum/Omni wheels" or "Study does not include people with motor impairments."
• Supplementary comparison table:
  A new Supplementary Table was added to support cross-study comparison using standardized performance parameters, including:
  Wheel type, Vibration reduction (%), Obstacle climbing height (mm), Battery type, Motor type / power, Cost strategy.
  This table allows readers to better understand key technical trade-offs between Mecanum and Omni systems. A reference to the supplementary table was added to the Data Availability Statement.
• Expanded reference base:
  Several new studies were added to ensure up-to-date coverage and meet the recommendation of including at least 60 references.

In direct response to the detailed feedback provided by Reviewer #3:

Reviewer comment:
The items in Tables 5 and 6 are relatively few, with only 1–2 rows. It is recommended to increase them to at least 3 rows, allowing for references that have appeared in the previous tables.

Response:
We appreciate the reviewer’s suggestion. In the revised manuscript, Tables 5 and 6 have been expanded to include additional studies previously mentioned in Sections 3.1–3.5. Specifically, Table 5 now includes a broader set of affordability-focused designs, while Table 6 incorporates additional projects involving real-world testing (e.g., by Matsuo [52] and Kang [53]). These updates improve representativeness and support clearer thematic synthesis.

Reviewer comment:
It is recommended to add at least 3 more references, for a total of 60 or more.

Response:
Thank you for this valuable recommendation. We have revised the reference list accordingly. The revised manuscript now includes a total of 60 references. Newly added citations include recent research on intelligent navigation, IoT integration, and field-oriented motor control (e.g., Ghanayem et al. [58]), which support the expanded discussion on automation, telehealth applications, and computational challenges [59-60].

We trust these changes address the reviewer’s concerns and improve the clarity and completeness of the manuscript.

 

Reviewer 4 Report

Comments and Suggestions for Authors

The revised manuscript on Mecanum and Omni wheel technologies for assistive mobility devices gives a broad summary of current research. It responds to some points raised in the first review. The authors added more content on real-world testing and more references about user-centered design. But the paper still has many problems. It does not give strong critical analysis. It does not fully cover user acceptance or cost issues. The structure and method also have problems. These issues lower the paper’s depth, clarity, and use in real situations. Below are the key problems and suggestions to help improve the paper.

 

1. The paper says it includes a qualitative review of study quality in Section 2.5. This is based on things like whether a prototype was built, how clearly the method was explained, and if the study listed its limits. But the paper does not give a clear set of rules or a framework for how this review was done. It also does not show how it checked for bias, such as small test groups or no blinding in user tests. This weakens the trust in the results. A better way is to use a standard tool made for engineering studies or to clearly list the rules used to judge each study.
2. The review does not often point out problems with how these studies were done. Many of them only used lab tests or did not include a wide range of users, such as people of different ages or types of disability. Section 3.6 does say that real-world testing is missing. But it does not explain how this affects how well the results can be used in daily life or over time. A better way would be to add a new part in the Discussion. This part should look closely at the limits of the studies. It should talk about the gap between lab tests and real-world use. It should also explain what this means for future work.
3. Sections 3 and 4 still have a lot of repeated content. Both talk about terrain handling, control systems, and energy use. For example, ideas like suspension systems and field-oriented control are explained in detail in both places. But the reason for showing them in each section is not clear. This repetition makes the paper harder to follow. A better way is to change the structure. The Results section should only show what the studies found. The Discussion should explain what the results mean, how they compare, and what future work is needed.
4. Table 1 (and others) remains difficult to navigate due to dense text and inconsistent subcategories.For example, the “Mobility Impact” and “Recommendations” columns mix written comments with a few numbers. This makes it hard to find the main points. A better way is to organize the tables using clear and short subcategories. These can include things like “Vibration Reduction,” “Max Obstacle Height,” or “Cost Estimate.” The tables should also show numbers when possible to make the data easier to compare.
5. The PRISMA diagram in Figure 2 still gives unclear reasons for removing some studies. For example, it says “Omni platform not intended for individuals with disabilities”[19-24], but does not explain what “intended” means or how this was checked. This weakens the method. A better way is to update the PRISMA diagram to use clear and specific reasons. For example, use “No working wheelchair prototype” or “Study does not include people with motor impairments.” These reasons should also match what is written in Section 2.1.
6. The review shows many designs but does not give a clear way to compare how they perform. Tables 1-6 have useful data, but the numbers and types of measures are not the same. This makes it hard to compare the results across studies. A better way is to create a new table that uses the same key metrics for each system. These could include things like percent of vibration reduction, battery life, or cost. The table should compare Mecanum and Omni wheel systems using these numbers.

Author Response

Dear Reviewer,

The revised version of the manuscript introduces substantial improvements based on reviewers' feedback. 

1.Reviewer comment:

The paper says it includes a qualitative review of study quality in Section 2.5. This is based on things like whether a prototype was built, how clearly the method was explained, and if the study listed its limits. But the paper does not give a clear set of rules or a framework for how this review was done. It also does not show how it checked for bias, such as small test groups or no blinding in user tests. This weakens the trust in the results. A better way is to use a standard tool made for engineering studies or to clearly list the rules used to judge each study.

Response:

We thank the reviewer for this valuable and insightful comment. In the revised manuscript, Section 2.5 (lines 146-162) has been substantially updated to clarify our approach to study quality and bias considerations.

We now explicitly state that no formal quality appraisal tool was applied, and no structured scoring or ranking of methodological rigor was conducted. Instead, we adopted a descriptive, qualitative approach aligned with the nature of the included studies, most of which followed engineering design or prototyping methodologies rather than clinical protocols.

Relevant indicators—such as the existence of a functional prototype, the presence of performance data, user involvement, and stated limitations—were systematically extracted and presented in Tables 1–6 to support comparative interpretation.

Furthermore, a new paragraph was added to acknowledge potential sources of bias (e.g., small or undefined participant samples, lack of blinding in control interface tests, and limited or artificial testing environments). While these factors were not formally quantified, they were carefully considered during thematic synthesis.

We also clarified that the decision not to use a structured quality assessment tool was due to the high heterogeneity in study design, scope, and reporting practices, which rendered uniform appraisal impractical.

Despite the absence of a formal risk of bias assessment, we emphasize that the methodological structure of this review—including predefined eligibility criteria, a comprehensive multi-database search, dual-reviewer screening, and structured thematic synthesis—aligns with PRISMA guidelines and supports its classification as a systematic review.

 

2.Reviewer comment:

The review does not often point out problems with how these studies were done. Many of them only used lab tests or did not include a wide range of users, such as people of different ages or types of disability. Section 3.6 does say that real-world testing is missing. But it does not explain how this affects how well the results can be used in daily life or over time. A better way would be to add a new part in the Discussion. This part should look closely at the limits of the studies. It should talk about the gap between lab tests and real-world use. It should also explain what this means for future work.

Response: We appreciate this insightful comment and agree that further elaboration on the limitations of existing studies was necessary. In response, we have significantly expanded the Discussion section to address this gap.

We now explicitly discuss how reliance on laboratory testing—with controlled environments and simplified obstacles—limits the generalizability of results and may overlook critical real-world factors such as environmental unpredictability, user fatigue, or support from caregivers. We also note that many studies used narrow participant profiles (e.g., young, able-bodied users), which restricts the relevance of findings for broader user populations, especially elderly individuals or those with cognitive impairments.

To address the reviewer’s recommendation, we added a new subsection within the Discussion that critically examines the gap between laboratory validation and daily life performance. This includes analysis of how real-world unpredictability affects reliability, safety, and user acceptance, and emphasizes the need for standardized field-testing protocols and inclusive evaluation strategies involving end-users at various stages.

Moreover, we highlight the implications for future research—namely, that technical optimization must be accompanied by ecological validation in diverse environments and with varied user groups. We believe these additions provide the depth and context needed to address the reviewer’s concern and enhance the practical relevance of the review’s findings. Bellow changed part of discussion:

 

Validation and real-world testing remain underdeveloped in this field. While some studies included pilot testing in homes or public spaces [50,52,53] , the majority relied on controlled environments with simplified obstacles. This limits generalizability and risks overlooking key factors such as user fatigue, caregiver support, environmental variability, or unstructured indoor layouts. Although Section 3.6 identifies this gap, its broader implications merit further attention. Devices that function well in standardized lab settings may underperform in real-world scenarios—on uneven terrain, in crowded spaces, or under changing weather conditions—where unpredictability directly affects usability, safety, and adoption.

Another limitation is the narrow user base involved in many studies, typically young and able-bodied individuals. This reduces the relevance of findings for elderly users or those with cognitive or motor impairments. Inclusive testing is essential to capture diverse needs and challenges, such as limited dexterity or increased cognitive load.

To overcome these shortcomings, future research should implement standardized field-testing protocols and participatory evaluation strategies involving real users from early development through post-deployment. Studies like those by Sivakanthan et al. [28] and Liu et al. [50] show that combining technical assessment with lived experience yields more actionable insights.

Furthermore, aligning specific engineering challenges with their testing methods—for example, verifying traction solutions on real slopes or validating energy efficiency across different user profiles—can improve transparency and guide future design decisions.

Finally, the lack of unified evaluation frameworks limits cross-study comparisons and benchmarking [55]. Establishing shared criteria and fostering collaboration among engineers, clinicians, and users will be key to refining omnidirectional assistive technologies for real-life use. Only through comprehensive validation—technical and experiential—can these innovations deliver consistent, inclusive, and safe mobility support.

 

3.Reviewer comment:

Sections 3 and 4 still have a lot of repeated content. Both talk about terrain handling, control systems, and energy use. For example, ideas like suspension systems and field-oriented control are explained in detail in both places. But the reason for showing them in each section is not clear. This repetition makes the paper harder to follow. A better way is to change the structure. The Results section should only show what the studies found. The Discussion should explain what the results mean, how they compare, and what future work is needed.

Response:

Thank you for this helpful suggestion. In response, we revised Sections 3 and 4 to ensure a clear separation between descriptive reporting and interpretive discussion. Section 3 now exclusively presents the factual content extracted from the reviewed studies—such as system architecture, control methods, testing conditions, and performance outcomes—without evaluative commentary.

 

4. Reviewer comment:

Table 1 (and others) remains difficult to navigate due to dense text and inconsistent subcategories.For example, the “Mobility Impact” and “Recommendations” columns mix written comments with a few numbers. This makes it hard to find the main points. A better way is to organize the tables using clear and short subcategories. These can include things like “Vibration Reduction,” “Max Obstacle Height,” or “Cost Estimate.” The tables should also show numbers when possible to make the data easier to compare.

Response:

In response, each table (Tables 1–6) was carefully reviewed and revised to eliminate redundancy, clarify terminology, and streamline the presented information.

As noted by other reviewers as well, the current table format—while not based on strict subcolumns—was considered acceptable due to the high heterogeneity of the included studies. The articles vary significantly in terms of scope, level of technical detail, and performance metrics reported. As such, creating uniform subcategories like “Vibration Reduction” or “Obstacle Height” across all entries would have led to incomplete or empty fields for many studies.

However, wherever numerical performance data were explicitly reported in the original articles, they have been retained in the tables (e.g., vibration reduction percentages, obstacle height, control accuracy). These values appear primarily in the “Mobility Impact” and “Performance” columns. For instance, the vibration reduction of 75% reported by Flores and Arias [31] is included in Table 1.

While the tables do still include narrative comments for context, we believe the revised layout strikes a reasonable balance between comparability and preserving the descriptive richness necessary to interpret design approaches.

5. Reviewer comment:

The PRISMA diagram in Figure 2 still gives unclear reasons for removing some studies. For example, it says “Omni platform not intended for individuals with disabilities”[19-24], but does not explain what “intended” means or how this was checked. This weakens the method. A better way is to update the PRISMA diagram to use clear and specific reasons. For example, use “No working wheelchair prototype” or “Study does not include people with motor impairments.” These reasons should also match what is written in Section 2.1.

Response:

 

Thank you for this helpful observation. In response, we have updated both the PRISMA diagram (Figure 2) and the eligibility criteria in Section 2.1 to provide clearer and more specific reasons for excluding studies.

The ambiguous phrase “Omni platform not intended for individuals with disabilities” was replaced with two explicit exclusion criteria:
(1) No working wheelchair prototype with Mecanum/Omni wheels
(2) Study does not include people with motor impairments

These criteria were consistently applied during full-text screening and are now reflected both in the PRISMA flowchart and in Section 2.1. This revision improves methodological transparency and ensures that study selection decisions are clearly documented and reproducible.

6. Reviewer comment:

The review shows many designs but does not give a clear way to compare how they perform. Tables 1-6 have useful data, but the numbers and types of measures are not the same. This makes it hard to compare the results across studies. A better way is to create a new table that uses the same key metrics for each system. These could include things like percent of vibration reduction, battery life, or cost. The table should compare Mecanum and Omni wheel systems using these numbers.

Response:

We fully agree with the reviewer that a standardized comparison table facilitates better interpretation across studies. However, due to the high heterogeneity in experimental design and reporting formats, it was not feasible to consolidate all performance metrics into the main text tables without oversimplifying or introducing bias.

To address this, we have compiled a new Supplementary Table that compares all included systems based on a set of consistent technical descriptors. These include:

Wheel type,

Vibration reduction (%),

Obstacle climbing height (mm),

Battery type,

Motor type / power,

Cost strategy.

This table reports only information explicitly stated in the original publications and avoids inferred or estimated values. It offers a structured, side-by-side view of each system’s core specifications and trade-offs. We hope this addition improves clarity and fulfils the reviewer’s recommendation for a comparative synthesis across Mecanum and Omni-based platforms.

Furthermore, a reference to this table has been added in the Data Availability Statement to ensure transparency and accessibility for readers.

We trust these changes address the reviewer’s concerns and improve the clarity and completeness of the manuscript.

 

 

 

Round 3

Reviewer 4 Report

Comments and Suggestions for Authors

no comments