**1. Introduction**

The thermoplastic materials do offer a great advantage over thermoset prepreg and dry fiber materials [1, 2]. For this advantage to be realized, thermoplastics must better compete with thermoset prepreg production for large structural parts in aviation. Today, most thermoplastic research has centered around full *in situ* consolidation to eliminate post-processing for curing. The main restriction of full *in situ* consolidation is on the speed (and productivity) of the LATP/LAFP process, which is limited by the physics or chemistry of thermoplastic materials. This method places all the demands of final part quality (low porosity, proper crystallinity, and autohesion) on the AFP process.

Robotic automated fiber/tape laying processes are used to produce highperformance composite components from unidirectional precast materials. In this

#### *Fiber-Reinforced Plastics*

procedure, a robot is most often used to lay the lanes along pre-defined paths, which provides a high degree of freedom in designing the final product. The process of automated laying of strips consists of automated laying, that is, stacking of layers on top of each other on a flat or complex-shaped tool, which is called a mandrel. Pre-layering is associated with the application of heat and pressure. It is important during this procedure to allow the strips to consolidate directly during installation, which will prevent additional time and energy from being spent on post-consolidation [3–7].

Most of the research for automated production is oriented toward the application of thermoplastic prepress materials, although today many responsible and loadbearing composite parts obtained with thermoset materials are in use [5]. The reason for such research is that when processing a thermoplastic prepreg, the material can be bonded on-site directly during layup (placement). However, when processing a thermoplastic prepreg, just like when processing a thermosetting prepreg, many challenging problems occur, such as gaps and overlaps between the tapes, which affects the final characteristics of the material, which requires in-depth research. The research done for the application of robotic processes for automatic laying of fibers/tapes is expected to provide better obtaining of high-quality structures from composite materials with a new process called on-site consolidation (*in situ*) [6–9].

The advantages and benefits of the application of these procedures for automated laying of fibers/tape for obtaining parts of composite materials are the following [4]:


The concept of *in situ* consolidation is simple. The inlet thermoplastic pretape in contact with the substrate or mandrel under sufficient pressure and temperature above the melting point is consolidated and crystallized upon cooling at the controlled or uncontrolled speed [10–25].
