Research

Jump to: Review

17 pages, 6264 KiB

Open AccessArticle

ROMI: Design and Experimental Evaluation of a Linear Delta Robotic System for High-Precision Applications

by Xiaoyu Huang, Elizabeth Rendon-Morales and Rodrigo Aviles-Espinosa

Machines 2023, 11(12), 1072; https://doi.org/10.3390/machines11121072 - 06 Dec 2023

Viewed by 1020

In this paper, the design and experimental evaluation of a parallel robotic system based on a linear delta geometry is presented. The design considers the requirements for high-precision applications including workspace, motion resolution, and payload. The entire design process includes robot kinematics, control, [...] Read more.

In this paper, the design and experimental evaluation of a parallel robotic system based on a linear delta geometry is presented. The design considers the requirements for high-precision applications including workspace, motion resolution, and payload. The entire design process includes robot kinematics, control, and optimization, resulting in the demonstration of a working device. The robot structure offers a versatile and simplified design when compared with state-of-the-art devices being able to be adapted to perform different tasks while keeping the advantages of high precision with reduced complexity. The presented robot prototype was constructed and evaluated experimentally through three proof-of-concept experiments mimicking tasks requiring high motion precision such as microsurgery, semiconductor testing, and optical device alignment. The obtained results in the three experimental scenarios validate that the here-proposed design can achieve an average motion precision of ~3.3 ± 0.3 μm with varying load conditions, thus confirming its potential to be used for high-precision tasks in industrial and medical settings. Full article

(This article belongs to the Special Issue New Trends in Robotics, Automation and Mechatronics)

► Show Figures

Figure 1

26 pages, 5610 KiB

Open AccessArticle

5G on the Farm: Evaluating Wireless Network Capabilities and Needs for Agricultural Robotics

by Tsvetan Zhivkov, Elizabeth I. Sklar, Duncan Botting and Simon Pearson

Machines 2023, 11(12), 1064; https://doi.org/10.3390/machines11121064 - 30 Nov 2023

Viewed by 1112

Abstract

Global food security is a critical issue today, strained by a wide range of factors including global warming, carbon emissions, sociopolitical and economic challenges, traditional workforce decline and population growth. Technical innovations that address food security, like agricultural robotics, are gaining traction in [...] Read more.

Global food security is a critical issue today, strained by a wide range of factors including global warming, carbon emissions, sociopolitical and economic challenges, traditional workforce decline and population growth. Technical innovations that address food security, like agricultural robotics, are gaining traction in industry settings, moving from controlled labs and experimental test facilities to real-world environments. Such technologies require sufficient network infrastructure to support in-field operations; thus, there is increased urgency to establish reliable, high-speed wireless communication networking solutions that enable deployment of autonomous agri-robots. The work presented here includes two contributions at the intersection of network infrastructure and in-field agricultural robotics. First, the physical performance of a private 5G-SA system in an agri-robotics application is evaluated and in-field experimental results are presented. These results are compared (using the same experimental setup) against public 4G and private WiFi6 (a newly emerging wireless communication standard). Second, a simulated experiment was performed to assess the “real-time” operational delay in critical tasks that may require quick turnaround between in-field robot and off-board processing. The results demonstrate that public 4G cannot be used in the agricultural domain for applications that require high throughput and reliable communication; that private 5G-SA greatly outperforms public 4G in all performance metrics (as expected); and that private WiFi6, though limited in range, is a fast and very reliable alternative in specific settings. While a single wireless solution does not currently exist for the agricultural domain, multiple technologies can be combined in a hybrid solution that meets the communications requirements. Full article

(This article belongs to the Special Issue New Trends in Robotics, Automation and Mechatronics)

► Show Figures

Figure 1

22 pages, 2908 KiB

Open AccessArticle

G-DMD: A Gated Recurrent Unit-Based Digital Elevation Model for Crop Height Measurement from Multispectral Drone Images

by Jinjin Wang, Nobuyuki Oishi, Phil Birch and Bao Kha Nguyen

Machines 2023, 11(12), 1049; https://doi.org/10.3390/machines11121049 - 25 Nov 2023

Viewed by 786

Abstract

Crop height is a vital indicator of growth conditions. Traditional drone image-based crop height measurement methods primarily rely on calculating the difference between the Digital Elevation Model (DEM) and the Digital Terrain Model (DTM). The calculation often needs more ground information, which remains [...] Read more.

Crop height is a vital indicator of growth conditions. Traditional drone image-based crop height measurement methods primarily rely on calculating the difference between the Digital Elevation Model (DEM) and the Digital Terrain Model (DTM). The calculation often needs more ground information, which remains labour-intensive and time-consuming. Moreover, the variations of terrains can further compromise the reliability of these ground models. In response to these challenges, we introduce G-DMD, a novel method based on Gated Recurrent Units (GRUs) using DEM and multispectral drone images to calculate the crop height. Our method enables the model to recognize the relation between crop height, elevation, and growth stages, eliminating reliance on DTM and thereby mitigating the effects of varied terrains. We also introduce a data preparation process to handle the unique DEM and multispectral image. Upon evaluation using a cotton dataset, our G-DMD method demonstrates a notable increase in accuracy for both maximum and average cotton height measurements, achieving a 34% and 72% reduction in Root Mean Square Error (RMSE) when compared with the traditional method. Compared to other combinations of model inputs, using DEM and multispectral drone images together as inputs results in the lowest error for estimating maximum cotton height. This approach demonstrates the potential of integrating deep learning techniques with drone-based remote sensing to achieve a more accurate, labour-efficient, and streamlined crop height assessment across varied terrains. Full article

(This article belongs to the Special Issue New Trends in Robotics, Automation and Mechatronics)

► Show Figures

Figure 1

21 pages, 11569 KiB

Open AccessArticle

A Novel Fully Automatic Concept to Produce First Subset of Bowden Cables, Improving Productivity, Flexibility, and Safety

by Eduardo Eiras, Francisco J. G. Silva, Raul D. S. G. Campilho, Rita C. M. Sales-Contini, André F. V. Pedroso and Naiara P. V. Sebbe

Machines 2023, 11(11), 992; https://doi.org/10.3390/machines11110992 - 26 Oct 2023

Viewed by 905

Abstract

With a view to maintaining the competitiveness required by the market, the automotive industry strongly encourages its suppliers to develop new production methods and technologies capable of reducing the costs of produced products, ensuring the necessary quality, and increasing flexibility, with a view [...] Read more.

With a view to maintaining the competitiveness required by the market, the automotive industry strongly encourages its suppliers to develop new production methods and technologies capable of reducing the costs of produced products, ensuring the necessary quality, and increasing flexibility, with a view to responding more easily to the customization of the products that the market increasingly demands. The main goal of this work was to increase the flexibility and productivity of equipment capable of producing the first subset that constitutes the product commonly known as the Bowden cable. To this end, the design science research methodology was used, which was understood as the most effective in describing scientific work related to the improvement of existing systems. Bowden cables are cables that activate various devices in the car, such as opening doors, moving window glasses, and adjusting some car seats, among others. The work consisted of integrating several operations usually carried out for the manufacture of the referred subset, reducing logistics operations and manual work, increasing operator safety, and increasing the production rate and flexibility of the equipment, by reducing the setup time. For this purpose, new mechanical concepts were developed, and automation was applied, which resulted in a completely new concept, able to fulfill all the objectives initially set. It should be noted here that the new equipment allowed a production rate of 1140 p/h, when the initial objective was 1100 p/h; it requires an investment of only around EUR 55,000 (easy return on investment), occupies only 11.6 m², and has reinforced safety systems to avoid workers’ injuries, an aspect that is very important in this type of equipment, where operators deal with cutting systems and high temperatures. The dissemination of this concept could help other researchers to easily find solutions to certain problems that they face in the development of modern equipment. The main contributions of this paper are the novel concepts created to overcome some process difficulties, which can be used for a wide range of other processing situations with similar difficulties. The solutions proposed allow a decrease in the cycle time, present high flexibility, save workshop space, and are affordable in terms of global cost. Full article

(This article belongs to the Special Issue New Trends in Robotics, Automation and Mechatronics)

► Show Figures

Figure 1

16 pages, 5763 KiB

Open AccessArticle

Grasping Pose Estimation for Robots Based on Convolutional Neural Networks

by Tianjiao Zheng, Chengzhi Wang, Yanduo Wan, Sikai Zhao, Jie Zhao, Debin Shan and Yanhe Zhu

Machines 2023, 11(10), 974; https://doi.org/10.3390/machines11100974 - 20 Oct 2023

Viewed by 1331

Abstract

Robots gradually have the ability to plan grasping actions in unknown scenes by learning the manipulation of typical scenes. The grasping pose estimation method, as a kind of end-to-end method, has rapidly developed in recent years because of its good generalization. In this [...] Read more.

Robots gradually have the ability to plan grasping actions in unknown scenes by learning the manipulation of typical scenes. The grasping pose estimation method, as a kind of end-to-end method, has rapidly developed in recent years because of its good generalization. In this paper, we present a grasping pose estimation method for robots based on convolutional neural networks. In this method, a convolutional neural network model was employed, which can output the grasping success rate, approach angle, and gripper opening width for the input voxel. The grasping dataset was produced, and the model was trained in the physical simulator. A position optimization of the robotic grasping was proposed according to the distribution of the object centroid to improve the grasping success rate. An experimental platform for robot grasping was established, and 11 common everyday objects were selected for the experiments. Grasping experiments involving the eleven objects individually, multiple objects, as well as a dark environment without illumination, were performed. The results show that the method has the adaptability to grasp different geometric objects, including irregular shapes, and it is not influenced by lighting conditions. The total grasping success rate was 88.2% for the individual objects and 81.1% for the cluttered scene. Full article

(This article belongs to the Special Issue New Trends in Robotics, Automation and Mechatronics)

► Show Figures

Figure 1

14 pages, 3300 KiB

Open AccessArticle

Multivariable Linear Position Control Based on Active Disturbance Rejection for Two Linear Slides Coupled to a Mass

by Fabio Abel Gómez Becerra, Jonathan Villanueva Tavira, Héctor Miguel Buenabad Arias, Andrés Blanco Ortega, Estela Sarmiento Bustos, Manuela Calixto Rodríguez and Jorge Salvador Valdez Martinez

Machines 2023, 11(9), 889; https://doi.org/10.3390/machines11090889 - 05 Sep 2023

Cited by 1 | Viewed by 693

Abstract

Active Disturbance Rejection Control (ADRC) is a promising approach that has emerged to deal with uncertainties, which has received many practical applications in motion controls. This paper presents a multivariable controller for active disturbance rejection (ADR) based on an extended state linear observer [...] Read more.

Active Disturbance Rejection Control (ADRC) is a promising approach that has emerged to deal with uncertainties, which has received many practical applications in motion controls. This paper presents a multivariable controller for active disturbance rejection (ADR) based on an extended state linear observer for tracking the linear position trajectory of a mass moved by two linear slides, each one driven by a DC motor. The linear extended state observer is used to estimate the endogenous and exogenous disturbances of the system, which are assumed to be unknown, but bounded. Therefore, the feedback system prevents each actuator from operating at different forward speeds, and thus a synchronization between the two actuators is achieved by moving the common mass smoothly. The simulation and the experimental results show the effectiveness and robustness of the controller proposal when moving the mass with both actuators. Full article

(This article belongs to the Special Issue New Trends in Robotics, Automation and Mechatronics)

► Show Figures

Figure 1

23 pages, 3129 KiB

Open AccessArticle

Fast Grasping Technique for Differentiated Mobile Phone Frame Based on Visual Guidance

by Rongli Zhao, Zeren Bao, Wanyu Xiao, Shangwen Zou, Guangxin Zou, Yuan Xie and Jiewu Leng

Machines 2023, 11(7), 689; https://doi.org/10.3390/machines11070689 - 30 Jun 2023

Viewed by 1151

Abstract

With the increasing automation of mobile phone assembly, industrial robots are gradually being used in production lines for loading and unloading operations. At present, industrial robots are mainly used in online teaching mode, in which the robot’s movement and path are set by [...] Read more.

With the increasing automation of mobile phone assembly, industrial robots are gradually being used in production lines for loading and unloading operations. At present, industrial robots are mainly used in online teaching mode, in which the robot’s movement and path are set by teaching in advance and then repeat the point-to-point operation. This mode of operation is less flexible and requires high professionalism in teaching and offline programming. When positioning and grasping different materials, the adjustment time is long, which affects the efficiency of production changeover. To solve the problem of poor adaptability of loading robots to differentiated products in mobile phone automatic assembly lines, it is necessary to quickly adjust the positioning and grasping of different models of mobile phone middle frames. Therefore, this paper proposes a highly adaptive grasping and positioning method for vision-guided right-angle robots. Full article

(This article belongs to the Special Issue New Trends in Robotics, Automation and Mechatronics)

► Show Figures

Figure 1

Review

Jump to: Research

20 pages, 409 KiB

Open AccessReview

Heuristics and Rescheduling in Prioritised Multi-Robot Path Planning: A Literature Review

by James R. Heselden and Gautham P. Das

Machines 2023, 11(11), 1033; https://doi.org/10.3390/machines11111033 - 20 Nov 2023

Cited by 1 | Viewed by 1134

Abstract

The benefits of multi-robot systems are substantial, bringing gains in efficiency, quality, and cost, and they are useful in a wide range of environments from warehouse automation, to agriculture and even extend in part to entertainment. In multi-robot system research, the main focus [...] Read more.

The benefits of multi-robot systems are substantial, bringing gains in efficiency, quality, and cost, and they are useful in a wide range of environments from warehouse automation, to agriculture and even extend in part to entertainment. In multi-robot system research, the main focus is on ensuring efficient coordination in the operation of the robots, both in task allocation and navigation. However, much of this research seldom strays from the theoretical bounds; there are many reasons for this, with the most-prominent and -impactful being resource limitations. This is especially true for research in areas such as multi-robot path planning (MRPP) and navigation coordination. This is a large issue in practice as many approaches are not designed with meaningful real-world implications in mind and are not scalable to large multi-robot systems. This survey aimed to look into the coordination and path-planning issues and challenges faced when working with multi-robot systems, especially those using a prioritised planning approach, and identify key areas that are not well-explored and the scope of applying existing MRPP approaches to real-world settings. Full article

(This article belongs to the Special Issue New Trends in Robotics, Automation and Mechatronics)

► Show Figures

Figure 1

27 pages, 1001 KiB

Open AccessReview

Deformable Object Manipulation in Caregiving Scenarios: A Review

by Liman Wang and Jihong Zhu

Machines 2023, 11(11), 1013; https://doi.org/10.3390/machines11111013 - 07 Nov 2023

Viewed by 1622

Abstract

This paper reviews the robotic manipulation of deformable objects in caregiving scenarios. Deformable objects like clothing, food, and medical supplies are ubiquitous in care tasks, yet pose modeling, control, and sensing challenges. This paper categorises caregiving deformable objects and analyses their distinct properties [...] Read more.

This paper reviews the robotic manipulation of deformable objects in caregiving scenarios. Deformable objects like clothing, food, and medical supplies are ubiquitous in care tasks, yet pose modeling, control, and sensing challenges. This paper categorises caregiving deformable objects and analyses their distinct properties influencing manipulation. Key sections examine progress in simulation, perception, planning, control, and system designs for deformable object manipulation, along with end-to-end deep learning’s potential. Hybrid analytical data-driven modeling shows promise. While laboratory successes have been achieved, real-world caregiving applications lag behind. Enhancing safety, speed, generalisation, and human compatibility is crucial for adoption. The review synthesises critical technologies, capabilities, and limitations, while also pointing to open challenges in deformable object manipulation for robotic caregiving. It provides a comprehensive reference for researchers tackling this socially valuable domain. In conclusion, multi-disciplinary innovations combining analytical and data-driven methods are needed to advance real-world robot performance and safety in deformable object manipulation for patient care. Full article

(This article belongs to the Special Issue New Trends in Robotics, Automation and Mechatronics)

► Show Figures

Figure 1

Journal Menu

Journal Browser

New Trends in Robotics, Automation and Mechatronics

Share This Special Issue

Special Issue Editor

Special Issue Information

Keywords

Published Papers (9 papers)

Research

Review

Further Information

Guidelines

MDPI Initiatives

Follow MDPI