## 1 Introduction  
The use of robots for handling and positioning, welding, subtractive and additive production has been expanding in recent years in line with the Industry 4.0 concept [1]. A robotic arm can be a separate mechanism or part of a more complex robot. It is a type of mechanical hand that is usually programmable and has similar functions to a human hand [2]. At present, we encounter the use of various production technologies in the production of robotic arm components. CNC machining technologies are the most widespread [3]. [PERSON] and [PERSON] [4] designed and validated a robotic arm made with two CNC machines. [PERSON] and [PERSON] are among the first researchers to compare the positioning accuracy of robotic arms made of conventional metallic materials and advanced composites [5]. Until recently, it was not possible to find a published use of an additive manufacturing component in an industrial robotic arm. However, the great expansion of 3D printing technology is creating increasingly suitable conditions for this [6]. A conventional 3D printer uses layering in a horizontal plane to produce a 3D printed part. [PERSON] and [PERSON] [7] proposed the integration of existing additive manufacturing process technologies with the arm of an industrial robot to create a multilayer layered 3D printer. Their approach allows printing to be layered in multiple planes, while existing conventional 3D printersare limited to one plane of the toolpath. The integration of the robotic arm and the extruder allows the movement of several planes of the tool path to be used in the production of structural parts. [PERSON] et al. [8] introduced a fast liquid printing device that can freely print in any direction, rather than layer by layer, depositing liquid material in a granular gel to create 3D structures. Recently, however, several scientific papers have appeared on the additive manufacturing of robotic arm components. [PERSON] et al. [9] proposed a prototype of a robotic arm made using 3D printing, which is also economically more advantageous compared to the price of an industrial robot thanks to conventional drives. [PERSON] et al. [10] implemented and validated a 3D printed open source robotic arm with 6 degrees of freedom made of ABS (Acrylonitrile Butadiene Styrene) material, due to higher mechanical strength. [PERSON] et al. [11] designed and developed a robotic arm for lifting light parts with 4 degrees of freedom. They used a 3D printing method to make the robotic arm components, which provided more accurate dimensions and time and cost savings. [PERSON] et al. [12] proposed a special holder for the InnoMotion robotic arm, where the main components of the holder were made by 3D printing using plastic material and are fully compatible with the MR and CT system and the robotic arm. The positioning accuracy of the robotic arm can vary widely in the workspace, which is influenced by various factors. Therefore, researchers propose various methods and methodologies to improve reliability and repeatability of positioning accuracy [13]. One of the parameters influencing the accuracy of the robotic arm is vibration. [PERSON] et al. [14] proposed a methodology to improve the estimation of kinematic parameters on industrial robots by correctly suppressing the vibrational components present on the signals obtained from the two primary sensors: the accelerometer and the gyroscope. Their results prove that the sensor fusion technique, accompanied by correct vibration suppression, provides a better estimate of the kinematic parameters than other proposed techniques. The accuracy of the robotic arm is also affected by sensing the position of each joint with a high-resolution optical coding device that cannot detect certain mechanical deformations, thus reducing the accuracy of the robot's positioning and orientation. Research in this area has been addressed by [PERSON] et al. [15], who developed an intelligent processor using Kalman filters to filter and fuse information from a network of sensors.