# Using a Cable-Driven Parallel Robot with Applications in 3D Concrete Printing
## 1 Introduction
The mobile robot is equipped with wheel encoders, an inertial measurement unit (IMU), and 2D laser scanner sensors for localization and odometry. The robots are controlled, positioned, and the motion trajectory set to work for each specific print object. [PERSON] et al. [4] showed the combination of the Cogiro cable-driven parallel robot (CDPR) (Cogiro is a suspended CDPR owned by Tecnalia and CNRS-LIRMM--Tecnalia France, 950 rue Saint-Priest, 34070 Montpellier, France) with the material extruder of the Pylos project (IAAC 2013) [5]; this system opens the opportunity to make a large 3D printing machine with a workspace of 13.69 \(\times\) 9.49 \(\times\) 3.3 m. Pylos is the product of a study at IAAC on 3D printing nozzles and materials for large-scale construction; the system is designed for extruding the construction materials. The material studied in this topic is from naturally sourced building materials and biodegradable, intended for printing in buildings. This material is the combination of a soil-based blend with a natural additive specially formulated to suit the extrusion of materials for construction, with improved tensile strength and viscosity. The material extruder is designed to consist of a material canister with a volume of 15 L; the extruded force is generated by a pneumatic cylinder. The print layer size is adjustable, with a layer thickness of 1-7 mm, width of 6-30 mm, and corresponding printing speed of 0.05-1 m/s. Its original point of design resides in the way the cables are connected to the frame, which makes it a very stable design, as studied by [PERSON] et al. [6]; this system is controlled by a G-Code post-processor module. In the study, the authors' cable-suspended parallel robot geometries relied on their quasi-static behavior, based on a particular wrench-feasibility analysis; the authors used a performance index, which is the maximum acceptable distance between the geometry center of the mobile platform and the center mass of the set consisting of the platform and payload. This performance index is used in determining the geometry of cable robots for heavy load handling applications, so that the ratio between the workspace and the size of the robot is large. Research into cable-driven parallel robots is an area of great interest in the field of robotics. Cable-driven parallel robots typically have greater load capacity, larger operating space, and, in particular, simpler portability and construction compared to traditional parallel robots like Hexapods, Delta robots, and serial robots [4; 7]. A CDPR (Figure 1) includes a moving platform (end-effector), cables, winches, and a base frame, with the cables being actuators used to connect the moving platform and base frame to which the winches are attached. The end-effector is moved by changing the length of the cables; this structure has a lot of advantages, especially when the moving platform is required to move at high acceleration because the weight of actuator is small. We also can put any load attaching moving platform CDPR to perform the different tasks during service and industrial activities. Furthermore, CDPRs have a flexible structure that can be easily reconfigured according to the workspace. CDPR frames can be factory frames, surrounding structures, or removable steel frames; this feature is particularly suitable for the construction of buildings due to construction sites and spaces being different. The weights of the winches are usually small compared to the large cable lengths, as well as convenient to move and install. However, certain problems, such as the complex dynamics and operating space, sagging of the cable over a large working distance, and the equilibrium status of the moving platform under external impact forces and positive cable tension conditions, are challenges to overcome when modeling and designing the cable robot controller, to ensure that the MP(moving platform) moves precisely according to the desired trajectory and with the required firmness.