Design and Tests of a Large-Opening Flexible Seedling Pick-Up Gripper with Multiple Grasping Pins

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The paper is generally well-structured and technically sound but can be improved from a writing and communication standpoint.  I feel the paper contributes to science and presents a practical solution for seedling transplanting.

Overall, grammar and clearly communicating points require improvement throughout the paper.  At times, sentences are too wordy making it difficult to understand the main point being made in the sentence.   For example, rather than use “...the pick-up gripper has some challenges to the success of seedling grasping...”, I suggest rewording and simplifying to “...poses challenges to successful seedling grasping...”.  Another suggestion would be to revise “...the pick-up gripper was moved by the automatic transplanting manipulator to approach the seedling’ root lump...”  and use “...the gripper was moved by the manipulator to approach the seedling’s root lump...”.  These types of revisions would help readers understand content and the point you are communicating. 

Additionally, "the", "a", "an" are sometimes misused or omitted.  Certain phrases and ideas are repeated unnecessarily, which could be removed or condensed for conciseness.  Another recommendation is that some sentences are overly long and could be condensed or broken into 2 sentences for improved readability. 

A couple of terms are used inconsistently or without clear definition such as “grasping effectiveness” and “transplanting success rate”.  You need to be consistent and use scientific terms.  Finally, I recommend stating objectives of the study at the end of the Introduction and revising the Conclusion section, so it aligns to what was learned.  The first sentence of the last paragraph in the Introduction notes “the aim” but more clearly stating objectives would improve the paper.

Detailed feedback are as follows:

Abstract

1. Suggest revising the first sentence as “The pick-up gripper, as a core component of automatic transplanting systems, presents challenges in reliably grasping seedlings.”
2. You not only develop but also evaluate the system. My suggestion would be to include “evaluated to optimize and understand performance” in the second sentence.  I prefer a stated objective for a journal article in the abstract but the second sentence is sufficient to indicate the intent of the paper.
3. Suggest the following revision for the third sentence (Lines 15-16) - “Structural design and force analysis were conducted to develop a functional prototype.”

 

Introduction

1. Introduction is well written.
2. Lines 35-37 - suggest revising to “In response to rising demand for agricultural products and diminishing resources, the adoption of automated agricultural systems offers a promising solution to enhance productivity and reduce labor costs.”
3. I would recommend having a stated objective or two in the last paragraph.

Materials and Methods

1. Lines 108-110 – suggest revising to “The gripper incorporates multiple fine pins to flexibly grasp the root lumps of seedlings.”
2. Lines 129 – 149 – present as a list versus different paragraphs.
3. Lines 155-156 – suggest “The grasping mechanism was developed through iterative theoretical calculations.”
4. Line 171 – Suggest “Therefore, the width between the two pin tips was set to 10–11 mm.”
5. Line 271 – explain what you mean by “unevenness of seedling growth”? Does this mean seedling height, biomass or plant material, etc.? 
6. Lines 280-281 – suggest revising to “The average grasping time was approximately 0.8 seconds, with an estimated service life of one million cycles.”
7. Figure 4b is hard to see the image itself. Can you enlarge the image?  If needed, maybe split Figure 4 into 2 separate figures.
8. Lines 296-298 – suggest revising to “A control system with an integrated power source was developed to enable point-to-point motion of the gripper between the source tray and the destination pots.”
9. An engineering question, while stainless steel pins were used, could other materials be used (e.g., composites or coated metals) to reduce further damage? You should consider as stating as future work or address this question in the discussion.
10. Pneumatic control is mentioned but could you provide a few more details on the control algorithms or feedback mechanisms?
11. I recommend describing how statistical analysis was performed.

 

Results and Discussion

1. Lines 346 -349 - suggest revising these sentences to “The optimal grasping parameters are presented in Table 2. Based on the range analysis (R values), the most influential factors on grasping integrity rates were the pin diameter and extraction speed, followed by penetration depth and grasping force.”
   1. The methods do not describe statistical analysis.
   2. R = correlation coefficient?
2. Lines 349-350 – suggest “The optimal combination of parameters was identified as A₂B₄C₃D₂.
3. Line 355, Table 2 – Report Y column to 1 decimal place. There needs to be a better explanation of the values presented across the 5 rows.  Are there R values presented in this table?
4. Lines 360-361 – suggest revising sentence to “The ANOVA results were consistent with the findings from the range analysis, reinforcing the significance of pin diameter and extraction speed.”
5. Lines 373-374 – suggest “Given the variation in material properties, future work could explore alternative pin materials to better suit different seedling types.”
6. Lines 410-411 – suggest “The transplanting success rate reflects the gripper’s overall efficiency in extracting, transferring, discharging, and planting seedlings.”
7. Line 418, Table 4 – present Success Rate of Transplanting as 1 decimal place.
8. Line 442 – suggest “Minor damage to cotyledons had minimal impact on subsequent seedling growth.”
9. Lines 448-449 – suggest using “These results further confirm that short, upright seedlings are better suited for mechanized transplanting.”
10. Question – could the study benefit from a broader range of seedling types and growth stages to assess robustness?
11. Any thoughts on how the prototype will be perform under field conditions? Any challenges it might face?

Conclusions

1. It would be suggested to revise this section and state what was learned around the development and performance of the pick-up gripper. There is no need to repeat any of the methods in this section, just state conclusions.
   1. Lines 480-481 – is this sentence needed? I recommend deleting since states “methods” used in the study. 
   2. Lines 486-488 – consider deleting this sentence.
2. Consider integrating metrics such as the ANOVA results into sentences to better support concluding statements.
3. Lines 481-484 suggest revising to “The results indicated that the end diameter of the pick-up pin and the vertical extraction speed significantly influenced the gripper’s performance.”
4. Lines 485-486 suggest “Excessive extraction force at higher speeds increased the risk of damaging the shaped substrate body.”
5. Lines 495-496 – I do not understand “specialized agronomy of vegetable seedling”? Please revise this sentence so it clearly states your point.

Comments on the Quality of English Language

Grammar and readability can be improved.  Comments provided in the notes to the author.

Author Response

<Reviewer: 1>

Comments for the Author:

The paper is generally well-structured and technically sound but can be improved from a writing and communication standpoint. I feel the paper contributes to science and presents a practical solution for seedling transplanting.

Overall, grammar and clearly communicating points require improvement throughout the paper. At times, sentences are too wordy making it difficult to understand the main point being made in the sentence. For example, rather than use “...the pick-up gripper has some challenges to the success of seedling grasping...” I suggest rewording and simplifying to “...poses challenges to successful seedling grasping...” Another suggestion would be to revise “...the pick-up gripper was moved by the automatic transplanting manipulator to approach the seedling’ root lump...” and use “...the gripper was moved by the manipulator to approach the seedling’s root lump...” These types of revisions would help readers understand content and the point you are communicating.

Additionally, "the", "a", "an" are sometimes misused or omitted. Certain phrases and ideas are repeated unnecessarily, which could be removed or condensed for conciseness. Another recommendation is that some sentences are overly long and could be condensed or broken into 2 sentences for improved readability.

A couple of terms are used inconsistently or without clear definition such as “grasping effectiveness” and “transplanting success rate”. You need to be consistent and use scientific terms. Finally, I recommend stating objectives of the study at the end of the Introduction and revising the Conclusion section, so it aligns to what was learned. The first sentence of the last paragraph in the Introduction notes “the aim” but more clearly stating objectives would improve the paper.

Response: Thanks for the reviewer's recognition. Improvement of agricultural mechanization will provide the strong technical support for agricultural production. The pick-up gripper, as a core component of automatic transplanting systems, presents challenges in reliably grasping seedlings. Based on this consideration, this paper is a research article about development of a large-opening flexible seedling pick-up gripper with multiple grasping pins. This research could provide innovative ideas for the development of precise seedling transplanting devices.

As the reviewers commented, the grammar and clearly communicating points require improvement throughout the paper. Additionally, the words of "the", "a", and "an" are sometimes misused or omitted. A couple of terms are used inconsistently or without clear definition. For English Language Editing, The paper has undergone English language editing by MDPI. The text has been checked for correct use of grammar and common technical terms, and edited to a level suitable for reporting research in a scholarly journal.

Abstract

1. Suggest revising the first sentence as “The pick-up gripper, as a core component of automatic transplanting systems, presents challenges in reliably grasping seedlings.”

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, the first sentence in the abstract has been revised in the manuscript.

2. You not only develop but also evaluate the system. My suggestion would be to include “evaluated to optimize and understand performance” in the second sentence.  I prefer a stated objective for a journal article in the abstract but the second sentence is sufficient to indicate the intent of the paper.

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, the second sentence in the abstract has been revised in the manuscript.

3. Suggest the following revision for the third sentence (Lines 15-16) - “Structural design and force analysis were conducted to develop a functional prototype.”

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, the third sentence in the abstract has been revised in the manuscript.

 

Introduction

1. Introduction is well written.

Response: Thanks for the reviewer's recognition. The authors have done their best to write a good introduction to clarify the research goal of the manuscript.

2. Lines 35-37 - suggest revising to “In response to rising demand for agricultural products and diminishing resources, the adoption of automated agricultural systems offers a promising solution to enhance productivity and reduce labor costs.”

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, the lines 35-37 sentence in the abstract has been revised in the manuscript.

3. I would recommend having a stated objective or two in the last paragraph.

Response: Thanks to the reviewer for your professional advice. The relevant content has been improved in the revised manuscript, which makes the introduction more reasonable and meaningful.

 

Materials and Methods

1. Lines 108-110 – suggest revising to “The gripper incorporates multiple fine pins to flexibly grasp the root lumps of seedlings.”

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, the lines 108-110 sentence has been revised in the manuscript. Such modification makes the description of the gripper more explicit.

2. Lines 129 – 149 – present as a list versus different paragraphs.

Response: Thanks to the reviewer for his meticulous review. At present, it is described in different paragraphs based on the working principle of the large-opening flexible seedling pick-up gripper. If the paper can be accepted by the journal, specific modifications will be considered according to the requirements of the journal.

3. Lines 155-156 – suggest “The grasping mechanism was developed through iterative theoretical calculations.”

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, the lines 155-156 sentence has been revised in the manuscript. Such modification makes the description of the grasping mechanism more explicit.

4. Line 171 – Suggest “Therefore, the width between the two pin tips was set to 10–11 mm.”

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, the lines 171 sentence has been revised in the manuscript. Such modification makes the description of the width more explicit.

5. Line 271 – explain what you mean by “unevenness of seedling growth”? Does this mean seedling height, biomass or plant material, etc.?

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, the lines 271 sentence has been revised in the manuscript. In the actual production scenarios, the unevenness of seedling growth, such as seedling heights, biomass and plant materials, might lead to differences in the seedling quality. Such modification makes the description of the seedling growth more explicit.

6. Lines 280-281 – suggest revising to “The average grasping time was approximately 0.8 seconds, with an estimated service life of one million cycles.”

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, the lines 280-281 sentence has been revised in the manuscript. Such modification makes the description of the industrial pneumatic fixture more explicit.

7. Figure 4b is hard to see the image itself. Can you enlarge the image? If needed, maybe split Figure 4 into 2 separate figures.

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, Figure 4b has been modified in the manuscript. Such modification makes the description of Figure 4b more explicit.

8. Lines 296-298 – suggest revising to “A control system with an integrated power source was developed to enable point-to-point motion of the gripper between the source tray and the destination pots.”

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, the lines 296-298 sentence has been revised in the manuscript. Such modification makes the description of the control system more explicit.

9. An engineering question, while stainless steel pins were used, could other materials be used (e.g., composites or coated metals) to reduce further damage? You should consider as stating as future work or address this question in the discussion.

Response: Thanks to the reviewer for your professional advice. To reduce further damage, other materials (e.g., composites or coated metals) can be considered for use in future work. It has been addressed this question in the discussion.

10. Pneumatic control is mentioned but could you provide a few more details on the control algorithms or feedback mechanisms?

Response: Thanks to the reviewer for your professional advice. For the pneumatic control, the instant response pneumatic circuits were designed as to sense these cylinders were sensed at each station. Specifically, when the electromagnetic coil was powered, the inlet and outlet of the solenoid control valves were quickly switched control the cylinder to perform the corresponding actions. Such an operation belongs to feedback mechanisms. It is very maturely applied in industrial technology.

11. I recommend describing how statistical analysis was performed.

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, the statistical analysis has been added in the manuscript. Such modification makes the description of the gripper more explicit.

 

Results and Discussion

1. Lines 346 -349 - suggest revising these sentences to “The optimal grasping parameters are presented in Table 2. Based on the range analysis (R values), the most influential factors on grasping integrity rates were the pin diameter and extraction speed, followed by penetration depth and grasping force.”
2. The methods do not describe statistical analysis.
3. R = correlation coefficient?

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, the lines 346 -349 sentence has been revised in the manuscript. Such modification makes the description of the results more explicit. Besides, the statistical analysis has been added in the manuscript. Here, the R value is the result based on the range analysis, and not the correlation coefficient.

2. Lines 349-350 – suggest “The optimal combination of parameters was identified as A₂B₄C₃D₂.

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, the lines 349-350 sentence has been revised in the manuscript. Such modification makes the description of the optimal combination more explicit.

3. Line 355, Table 2 – Report Y column to 1 decimal place. There needs to be a better explanation of the values presented across the 5 rows.  Are there R values presented in this table?

Response: Thanks to the reviewer for his meticulous review. Report Y column with two decimal places is more persuasive. The values presented across the 5 rows are widely adopted formats in the orthogonal experimental design. If needed, Table 2 may be split into 2 separate tables. Here, the R value is the result based on the range analysis above these K values. Therefore, there R values are presented in this table.

4. Lines 360-361 – suggest revising sentence to “The ANOVA results were consistent with the findings from the range analysis, reinforcing the significance of pin diameter and extraction speed.”

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, the lines 360-361 sentence has been revised in the manuscript. Such modification makes the description of the ANOVA results more explicit.

5. Lines 373-374 – suggest “Given the variation in material properties, future work could explore alternative pin materials to better suit different seedling types.”

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, the lines 373-374 sentence has been revised in the manuscript. Such modification makes the description of the pin materials more explicit.

6. Lines 410-411 – suggest “The transplanting success rate reflects the gripper’s overall efficiency in extracting, transferring, discharging, and planting seedlings.”

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, the lines 410-411 sentence has been revised in the manuscript. Such modification makes the description of the transplanting success rate more explicit.

7. Line 418, Table 4 – present Success Rate of Transplanting as 1 decimal place.

Response: Thanks to the reviewer for his meticulous review. Report Y column with two decimal places is more persuasive. If the journal requires 1 decimal place for data, it is very easy to modify them.

8. Line 442 – suggest “Minor damage to cotyledons had minimal impact on subsequent seedling growth.”

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, the lines 442 sentence has been revised in the manuscript. Such modification makes the description of the minor damage more explicit.

9. Lines 448-449 – suggest using “These results further confirm that short, upright seedlings are better suited for mechanized transplanting.”

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, the lines 448-449 sentence has been revised in the manuscript. Such modification makes the description of the results suited for mechanized transplanting more explicit.

10. Question – could the study benefit from a broader range of seedling types and growth stages to assess robustness?

Response: Thanks to the reviewer for his meticulous review. Three typical vegetable seedlings have been studied in the manuscript. In future, the specialized agronomy of vegetable seedling qualities should be combined with automatic transplanting operations.

11. Any thoughts on how the prototype will be perform under field conditions? Any challenges it might face?

Response: Thanks to the reviewer for his meticulous review. Although the prototype seems to be studied in the laboratory, it is intended at the beginning of this study to concentrate our efforts on making the function of the new gripper more accurate. Taking three typical vegetable seedlings as the transplanting objects, some performance tests have been conducted to verify the optimal operation parameters. The tests can also be used to evaluate the practicality and adaptability of the new gripper. In future, the prototype will be performed under various field conditions.

 

Conclusions

1. It would be suggested to revise this section and state what was learned around the development and performance of the pick-up gripper. There is no need to repeat any of the methods in this section, just state conclusions.
   1. Lines 480-481 – is this sentence needed? I recommend deleting since states “methods” used in the study. 
   2. Lines 486-488 – consider deleting this sentence.

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, the corresponding sentence has been revised in the manuscript. This manuscript is about the research on the innovative optimization of the new gripper. Besides the expression of the key structure, it is still necessary to provide relevant research conclusions as much as possible.

2. Consider integrating metrics such as the ANOVA results into sentences to better support concluding statements.

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, the ANOVA results have been added in the manuscript. Such modification makes the description of the concluding statements more explicit.

3. Lines 481-484 suggest revising to “The results indicated that the end diameter of the pick-up pin and the vertical extraction speed significantly influenced the gripper’s performance.”

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, the lines 481-484 sentence has been revised in the manuscript. Such modification makes the description of the results more explicit.

4. Lines 485-486 suggest “Excessive extraction force at higher speeds increased the risk of damaging the shaped substrate body.”

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, the lines 485-486 sentence has been revised in the manuscript. Such modification makes the description of the r extraction force more explicit.

5. Lines 495-496 – I do not understand “specialized agronomy of vegetable seedling”? Please revise this sentence so it clearly states your point.

Response: Thanks to the reviewer for your professional advice. Following the reviewer's advice, the lines 495-496 sentence has been revised in the manuscript. In fact, there is consequently a need for a vegetable-specific study on seedling qualities for compatibility with automatic transplanting operations.

 

Finally, the authors thank the reviewer for your help for improving the quality of this manuscript.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Work important for agricultural practice, but also in tree and shrub nurseries. It is also worth looking for solutions that are already in use and are good there. In Europe, such work is carried out, for example, by https://pit.lukasiewicz.gov.pl/
Today, solutions are also sought in bionics for such activities. Bionics allows the use of solutions developed by nature during evolution in production engineering. Living organisms (rats, rabbits and here perhaps moles) have adapted their structure and body covering to safely and rationally perform basic life activities. Many of these patents of nature can be an inspiration for solving engineering problems. Bionics is also used in agricultural technology. Tools for separating/cutting/harvesting materials and probably also transplanting plant seedlings use bioinspiration.
In turn, in order to ensure greater than 95% effectiveness of the prototype's work, techniques allowed by YOLO computer systems can be used - for precise identification of objects.
The results lack measurement uncertainty, and providing percentage values ​​to 2 decimal places only obscures the meaning of these results (e.g. line 413) – as in line 493. What are the durability and reliability results of the proposed technical solution? Difficult environmental conditions require good construction materials and quality of workmanship.

Author Response

Review 2

Work important for agricultural practice, but also in tree and shrub nurseries. It is also worth looking for solutions that are already in use and are good there. In Europe, such work is carried out, for example, by https://pit.lukasiewicz.gov.pl/
Today, solutions are also sought in bionics for such activities. Bionics allows the use of solutions developed by nature during evolution in production engineering. Living organisms (rats, rabbits and here perhaps moles) have adapted their structure and body covering to safely and rationally perform basic life activities. Many of these patents of nature can be an inspiration for solving engineering problems. Bionics is also used in agricultural technology. Tools for separating/cutting/harvesting materials and probably also transplanting plant seedlings use bioinspiration.
In turn, in order to ensure greater than 95% effectiveness of the prototype's work, techniques allowed by YOLO computer systems can be used - for precise identification of objects.
The results lack measurement uncertainty, and providing percentage values ​​to 2 decimal places only obscures the meaning of these results (e.g. line 413) – as in line 493. What are the durability and reliability results of the proposed technical solution? Difficult environmental conditions require good construction materials and quality of workmanship.

Response: Thanks for the reviewer's recognition. This study is an important work for agricultural practice. It can be also used in tree and shrub nurseries.

Today, solutions are also sought in bionics for such activities. In the future, some bionic grasping mechanisms can be explored to reliably pick up seedlings.

This new pick-up gripper did not compensate for blank cells and unhealthy seedlings in the trays. However, if the blank cells and unhealthy seedlings in the trays could be filled by another intelligent robotic system, the automatic transplanting performance would be better. As the reviewer stated, in order to ensure greater than 95% effectiveness of the prototype's work, techniques allowed by YOLO computer systems can be used for precise identification of objects.

Although the prototype seems to be studied in the laboratory, it is intended at the beginning of this study to concentrate our efforts on making the function of the new gripper more accurate. Taking three typical vegetable seedlings as the transplanting objects, some performance tests have been conducted to verify the optimal operation parameters. The tests can also be used to evaluate the practicality and adaptability of the new gripper. In future, the prototype will be performed under various field conditions.