The Design of a New Manual Wheelchair for Sport
Round 1
Reviewer 1 Report
The manuscript entitled the Design of a new manual wheelchair for sport documents early design of a new manual wheelchair. The authors describe a new system for propulsion based on a rowing movement. There are some English language changes required however I feel this paper needs major revisions in terms of methodology and scientific evidence so I will highlight these.
The main reason for this is the new wheelchair propulsion system inferred through the paper would be to improve biomechanical efficiency and mitigate against injury, to this end I am not confident that the proposed system achieves this. The rowing gesture alone is mentioned, but there are no rowing biomechanics papers cited. My issue is that classically rowing is divided into 4 phases (catch, drive, release, recovery). The shoulder and arms provide a connection for power for rowing, but the drive phase uses lower leg power to propel the boat. This is an issue with suggesting a rowing like motion is kinematically optimal for wheelchair users as they do not have this propulsive mechanism. I am not sure if this movement is more efficient then regular wheelchairs or will reduce injury and the scientific evidence of this needs to be communicated.
The large problem I have with the study is that no methods are presented which aim to show that injuries will be reduced. I think any mechanism which compares the efficiency of this system should compare the new proposed system, to that of a conventional wheelchair and to recumbent handcycling. This can be done numerically / using CAE simulations etc. to show how the new system is superior, or of course through prototyping and physical testing. Currently the paper, seems like a proof of concept with a few concept sketches, however there is limited scientific argument to substantiate the authors proposed design. This ultimately results in a very limited scientific worth and as optimization methods of how the authors have got to the final result, the scientific biases for the result is small. I look forward to the authors addressing this problem in more depth as ultimately improved mobility for people with a disability is a tremendously important goal and has wider societal implications.
Author Response
Reply to Reviewers’ Comments
We would like to thank the reviewers for their comments and valuable suggestions.
Reviewers’ comments are printed in black.
Our comments are printed in blue.
Modifications to the manuscript are printed in red.
Reviewer #1:
The main reason for this is the new wheelchair propulsion system inferred through the paper would be to improve biomechanical efficiency and mitigate against injury, to this end I am not confident that the proposed system achieves this.
We modified the beginning of section 2:
The innovative system of propulsion is inspired by the rowing gesture. The main characteristic of the rowing gesture, during the drive phase, is that the movement of the arm is a pulling movement instead of pushing movement. The pulling movement, applied to wheelchairs, could be a good alternative compared to the pushing movement.
The rowing gesture alone is mentioned, but there are no rowing biomechanics papers cited. My issue is that classically rowing is divided into 4 phases (catch, drive, release, recovery). The shoulder and arms provide a connection for power for rowing, but the drive phase uses lower leg power to propel the boat. This is an issue with suggesting a rowing like motion is kinematically optimal for wheelchair users as they do not have this propulsive mechanism
We added the references [16, 17, 18, 23] and we added a description about the rowing stroke in the Introduction:
The rowing stroke [16] is divided in four phases and different articles evaluate the efficiency of the gesture in different ways [17]. The rowing stroke is a complex movement, the muscles of the legs, trunk, back, shoulders and arms are involved. The rowing stroke can be performed by disabled athletes with different levels of spinal injuries [18]. Disabled people can perform the rowing stroke depending on the height of the spinal injuries.
I am not sure if this movement is more efficient then regular wheelchairs or will reduce injury and the scientific evidence of this needs to be communicated.
As you rightly said above, the prototype is in the development phase and we are not sure about the superior of the “innovative system”, but we are proposing an option that has to be evaluated.
The reference [13, 14, 15] described accurately some critical issues of the handrim and lever system. In particular, [13] highlights the peaks of force on shoulder using the handrim system and handbike, [14] studies the efficiency of the handrim system and [15] compares the lever and handrim system.
The large problem I have with the study is that no methods are presented which aim to show that injuries will be reduced. I think any mechanism which compares the efficiency of this system should compare the new proposed system, to that of a conventional wheelchair and to recumbent handcycling. This can be done numerically / using CAE simulations etc. to show how the new system is superior, or of course through prototyping and physical testing. Currently the paper, seems like a proof of concept with a few concept sketches, however there is limited scientific argument to substantiate the authors proposed design. This ultimately results in a very limited scientific worth and as optimization methods of how the authors have got to the final result, the scientific biases for the result is small. I look forward to the authors addressing this problem in more depth as ultimately improved mobility for people with a disability is a tremendously important goal and has wider societal implications.
We added the paragraph 5. We presented a dynamic model of Handwheelchair.q and the results obtained by using the software Matlab/Simulink.
Author Response File: 
Author Response.doc
Reviewer 2 Report
The paper presents a new design for manual wheelchair, in which a pulley, cable, ratchets, power recovery spring are used in order to reduce injuries caused by driving with the contact of the user's hand with the hand rim. Its principle, applications and practical constructions are presented.
In the paper, the authors called the proposed design as "innovative system". The reviewer can personally agree with this, however, some supportive results are needed to show its innovative feature. In the last part, the authors showed free body diagram and equations of motions. By using these formulations, the reviewer suggests the authors to show a demonstrative example (numerical example), or comprehensive explanation of the feature of the proposed design using the formulation is also supportive.
Author Response
Reply to Reviewers’ Comments
We would like to thank the reviewers for their comments and valuable suggestions.
Reviewers’ comments are printed in black.
Our comments are printed in blue.
Modifications to the manuscript are printed in red.
Reviewer #2:
In the last part, the authors showed free body diagram and equations of motions. By using these formulations, the reviewer suggests the authors to show a demonstrative example (numerical example), or comprehensive explanation of the feature of the proposed design using the formulation is also supportive.
We added the paragraph 5. Dynamic model of Handwheelchair.q.
In this paragraph we studied a dynamic model of handwheelchair.q with the software Matlab/Simulink. The preliminary results of the dynamic model of Handwheelchair.q are shown.
Author Response File: Author Response.doc
Round 2
Reviewer 2 Report
The paper has been well revised. With the revisions according to the other reviewers, the quality and contents of the paper has been improved.
Let me note that there are some typos to be polished.
Author Response
Dear reviewer,
Thank you for your right comments.
We corrected many typos and we standardized the format of the formulas, of the tables and of the text.
