Using a Cable-Driven Parallel Robot with Applications in 3D Concrete Printing

In construction, a large-scale 3D printing method for construction is used to build houses quickly, based on Computerized Aid Design. Currently, the construction industry is beginning to apply quite a lot of 3D printing technologies to create buildings that require a quick construction time and complex structures that classical methods cannot implement. In this paper, a Cable-Driven Parallel Robot (CDPR) is described for the 3D printing of concrete for building a house. The CDPR structures are designed to be suitable for 3D printing in a large workspace. A linear programming algorithm was used to quickly calculate the inverse kinematic problem with the force equilibrium condition for the moving platform; this method is suitable for the flexible configuration of a CDPR corresponding to the various spaces. Cable sagging was also analyzed by the Trust-Region-Dogleg algorithm to increase the accuracy of the inverse kinematic problem for controlling the robot to perform basic trajectory interpolation movements. The paper also covers the design and analysis of a concrete extruder for the 3D printing method. The analytical results are experimented with based on a prototype of the CDPR to evaluate the work ability and suitability of this design. The results show that this design is suitable for 3D printing in construction, with high precision and a stable trajectory printing. The robot configuration can be easily adjusted and calculated to suit the construction space, while maintaining rigidity as well as an adequate operating space. The actuators are compact, easy to disassemble and move, and capable of accommodating a wide variety of dimensions.

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An analytical and a Deep Learning model for solving the inverse kinematic problem of an industrial parallel robot

Computers & Industrial Engineering ◽

10.1016/j.cie.2020.106682 ◽

2020 ◽

pp. 106682

Author(s):

Juan S. Toquica ◽

Patrícia S. Oliveira ◽

Witenberg S.R. Souza ◽

José Maurício S.T. Motta ◽

Díbio L. Borges

Keyword(s):

Deep Learning ◽

Parallel Robot ◽

Learning Model ◽

Inverse Kinematic ◽

Inverse Kinematic Problem ◽

Deep Learning Model

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Workspace and Stiffness Analysis of 3D Printing Cable-Driven Parallel Robot with a Retractable Beam-Type End-Effector

Robotics ◽

10.3390/robotics9030065 ◽

2020 ◽

Vol 9 (3) ◽

pp. 65

Author(s):

Jinwoo Jung

Keyword(s):

3D Printing ◽

Natural Frequencies ◽

Parallel Robot ◽

Good Alternative ◽

Construction Time ◽

Single Plane ◽

End Effector ◽

Stiffness Analysis ◽

Position Errors ◽

Beam Type

3D printing is a widely used technology that has been recently applied in construction to reduce construction time significantly. A large 3D printer often uses a traditional Cartesian robot with inherent problems, such as position errors and printing nozzle vibrations, due to the long, heavy horizontal beam carrying it and a large amount of power required to actuate the heavy beam. A cable-driven parallel robot (CDPR) can be a good alternative system to reduce the vibrations and necessary power because the robot’s lightweight cables can manipulate the printing nozzle. However, a large 3D printing CDPR should be carefully designed to maximize the workspace and avoid cable interference. It also needs to be stiff enough to reject disturbances from the environment properly. A CDPR with a retractable beam-type end-effector with cables through the guide pulleys in a single plane is suggested for avoiding cable interference while maximizing the workspace. The effects of using the retractable end-effector on the workspace were analyzed relative to the cable connection points’ location changes. Static stiffness analysis was conducted to examine the natural frequencies, and the geometric parameters of the end-effector were adjusted to improve the lowest natural frequencies. Simulation results show that a retractable beam-type end-effector can effectively expand the wrench-feasible workspace.

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Empirical Quasi-Static and Inverse Kinematics of Cable-Driven Parallel Manipulators Including Presence of Sagging

Applied Sciences ◽

10.3390/app10155318 ◽

2020 ◽

Vol 10 (15) ◽

pp. 5318

Author(s):

Phan Gia Luan ◽

Nguyen Truong Thinh

Keyword(s):

Kinematic Model ◽

Static Problem ◽

Parallel Manipulators ◽

Parallel Robot ◽

Inverse Kinematic ◽

Inverse Kinematic Problem ◽

Redundant Actuators ◽

Small Change ◽

Feasible Solutions ◽

Flexible Cables

Cable-driven parallel manipulators (CDPMs) have been of great interest to researchers in recent years because they have many advantages compared to the traditional parallel robot. However, in many studies they lack the cable’s elasticity that leads to flexible cables just being considered as extendable rigid links. Furthermore, an external force acts on the extremities of cable and the self-weight is relevant to the length of it. Experimentally, a small change in length produces a huge change in tension act on the entire cable. By this property, the adjusting length of cable is often added to the traditional inverse kinematic solution in order to reduce the tension force exerted on the cable. This means that the load on the actuator is also reduced. Because of the relationship between tension that acts on the cable and its length, the kinematic problem itself does not make sense without concerning the static or dynamic problems. There is often interest in planning forces for actuators and the length of cables based on a given quasi-static trajectory of the moving platform. The mentioned problem is combined with the quasi-static problem with the inverse kinematic problem of CDPM. In this study, we introduce a novel procedure to produce the quasi-static model and inverse kinematic model for CDPM with the presence of sagging by using both an analytic approach and empirical approach. The produced model is time-efficient and is generalized for spatial CDPM. To illustrate the performance of the proposed model, the numerical and experimental approaches are employed to determine particular solutions in the feasible solutions set produced by our model in order to control the two redundant actuators’ CDPM tracking on a certain desired trajectory. Its results are clearly described in the experimental section.

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Collision-Free and Energy-Saving Trajectory Planning for Large-Scale Redundant Manipulator Using Improved PSO

Mathematical Problems in Engineering ◽

10.1155/2013/208628 ◽

2013 ◽

Vol 2013 ◽

pp. 1-8 ◽

Cited By ~ 4

Author(s):

Min Jin ◽

Dan Wu

Keyword(s):

Energy Saving ◽

Trajectory Planning ◽

Large Scale ◽

Pso Algorithm ◽

Inverse Kinematic ◽

Outdoor Environment ◽

Inverse Kinematic Problem ◽

Concrete Pump Truck ◽

Concrete Pump ◽

Improved Pso

The large-scale boom system, such as the five-arm concrete pump truck with the arm length of 36–65 meters, usually operates in an unknown dynamic outdoor environment. The motion safety and the energy consumption are thus the two vital measurements to the effectiveness of the trajectory planning for the large-scale boom system. Due to the redundancy of the large-scale boom system and some drawbacks of the original particle swarm optimization (PSO) algorithm, an improved PSO algorithm is presented to solve the inverse kinematic problem of the redundant large-scale boom system. By the improved PSO algorithm, the energy-saving trajectory planning of the large-scale boom system that operates in a workspace without obstacles and with obstacles is optimized, which considers different important degrees of the subgoals, respectively. The optimal results from the simulation study and the practical application verify the effectiveness of the proposed planning strategy. At the same time, the performance of the improved strategy is compared with that of the traditional, and the superiority is further demonstrated.

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A Review of 3D Printing in Construction and its Impact on the Labor Market

Sustainability ◽

10.3390/su12208492 ◽

2020 ◽

Vol 12 (20) ◽

pp. 8492

Author(s):

Md. Aslam Hossain ◽

Altynay Zhumabekova ◽

Suvash Chandra Paul ◽

Jong Ryeol Kim

Keyword(s):

Labor Market ◽

3D Printing ◽

Construction Industry ◽

Construction Projects ◽

Large Scale ◽

New Technology ◽

Immigrant Workers ◽

Technological Innovations ◽

Construction Time ◽

Laborious Work

Construction industry is very labor-intensive and one of the major sources of employment in the world. The industry is experiencing low productivity with minimum technological innovations for decades. In recent times, various automation technologies including 3D printing have received increasing interests in construction. 3D printing in construction is found to be very promising to automate the construction processes and have the potential of saving laborious work, material waste, construction time, risky operation for humans, etc. There has been a comprehensive body of research conducted to understand the recent advances, future prospects and challenges of large-scale adoption of 3D printing in construction projects. Being one the labor-intensive industries, this study also investigates the possible impact on the labor market with increasing adoption of 3D printing in construction. It is found that 3D printing can reduce significant number of labors which can solve the labor shortage problem, especially for the countries where construction is heavily dependent on immigrant workers. In contrast, 3D printing might not be favorable for the countries where construction is one of the main workforces and labor is less expensive. Moreover, 3D construction printing will also require people with special skills related to this new technology.

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Exploiting Redundancies for Workspace Enlargement and Joint Trajectory Optimisation of a Kinematically Redundant Hybrid Parallel Robot

Journal of Mechanisms and Robotics ◽

10.1115/1.4050681 ◽

2021 ◽

pp. 1-12

Author(s):

Kefei Wen ◽

Clement Gosselin

Keyword(s):

Performance Index ◽

Degrees Of Freedom ◽

Parallel Robot ◽

Inverse Kinematic ◽

Parallel Robots ◽

New Method ◽

Inverse Kinematic Problem ◽

Redundant Robots ◽

Joint Coordinates ◽

Trajectory Optimisation

Abstract In this paper, possibilities for workspace enlargement and joint trajectory optimisation of a (6+3)-degree-of-freedom kinematically redundant hybrid parallel robot are investigated. The inverse kinematic problem of the robot can be solved analytically, which is a desirable property of redundant robots, and is implemented in the investigations. A new method for detecting mechanical interferences between two links which are not directly connected is proposed for evaluating the workspace. Redundant degrees of freedom are optimised in order to further expand the workspace. An approach for determining the desired redundant joint coordinates is developed so that a performance index can be minimised approximately when the robot is following a prescribed Cartesian trajectory. The presented approaches are readily applicable to other kinematically redundant hybrid parallel robots proposed by the authors.

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