Design and Analysis of a Robotic Gripper Mechanism for Fruit Picking

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

In this paper, the author describes “Design and analysis of a robotic gripper mechanism for fruit picking”. It can become an interesting paper for Actuators after major revision. Followings are my comments.

(1)   Abstract should be improved and extended. The novelty of the proposed model is missing. Please be specific what are the main quantitative results to attract general audiences.

(2)   The novelty of the proposed method is unclear. Reviewer considers the novelty of this study to be a good design of a robotic gripper mechanism for low-damage gripper. Therefore, this study has to provide the results of force analysis for gripping the various fruits. For example, how to grip the apple, zucchini, and so on? What are the force effects of gripping for the various fruits? Finally, authors discuss the results.

(3)   Reviewer does not realize how to use rotation gears to control the rotation positions of fingers in Figure 2. Authors have to use diagrams to explain how to control the rotation position of fingers by using the rotation gears of Figure 1.

(4)   Why does this study use ABS and Rubber materials for robotic grippers?

(5)   Reviewer does not find the simulation results of static stress analysis of the robotic gripper by using rubber material. Authors have to provide them.

(6)   Reviewer does not realize the meanings of “the total grasping motion time is 2-3 times longer under the driving speed of 5 mm/s” and “At the higher drive speeds 10 mm/s and 15 mm/s, the knuckle response speed is doubled, but so is the reduction in angular velocity in the second half of the motion”.

(7)   Reviewer also does not realize the results of Figures 8 and 9. Why are the results of 10 mm/s and 15 mm/s in a short time in Figure 8? And, why do the results of 10 mm/s and 15 mm/s first decay to 0 and then increase for angular acceleration in Figure 9?

(8)   As the journal is printed in black and white, please make the different markers for the different results in Figs. 8, 9, and 10.

 

(9)   According to SI units, authors have to give a space between numbers and units in this paper (including figures).

Comments on the Quality of English Language

Minor editing of English language required.

Author Response

Sincerely thank you for your review. Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The paper titled “Design and analysis of a robotic gripper mechanism for fruit picking” discusses the design, analysis, implementation, and testing of a three-finger gripper capable of grasping various spherical or cylindrical fruits. The design scheme and working principles are well-explained. Gripper force calculations and stress analysis are conducted thoroughly. However, testing and performance reporting of the gripper needs improvements. My comments are as follows:

• Figure 12: All fruits appear to be gripped under ideal conditions. It seems like the fruits are manually fed to the gripper. Have you attempted to harvest fruits directly from plants or trees?

• Table 3 and Table 4: Are the values presented the averages of a certain number of fruits or are they based on a single fruit? Please specify this in the paper.

• There are numerous fruit and vegetable grippers available in the market. How does your gripper differ from these existing options? Commercial grippers often utilize soft materials and suction mechanisms to handle delicate fruits, whereas your gripper features rigid fingers. How does this design choice offer advantages over other grippers? Please address this in your conclusion.

• Were the tests conducted to measure forces static? In real-world applications, grippers will be in motion during harvesting. Acceleration and deceleration during motion can alter force requirements. Did you account for these factors in your testing? If not, please mention your test conditions in the paper.

Thank you!

Comments on the Quality of English Language

Nothing major. 

Author Response

Sincerely thank you for your review. Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Reviewer recommends to accept without comments.

Reviewer 2 Report

Comments and Suggestions for Authors

Dear Authors: 

Thank you for updating the manuscript. Some of the comments, such as grasping directly from a plant/tree, are not yet addressed but I can see that those are added for the future work as listed in Conclusion. 

Good luck!