## 1 Introduction
They used two primary sensors: an optical encoder and a 3-axis accelerometer. Calibration of a robot arm is an important factor in the accuracy of robot positioning. A simple, low-cost calibration procedure that improves the surface positioning accuracy of a SCARA (Selective Compliance Assembly Robot Arm) double-arm robot was published by [PERSON] et al. [16]. One of the key problems in examining the positioning accuracy of robotic arms is the working temperature. [PERSON] et al. Analyzed the analysis of the influence of temperature on the positioning accuracy of the robot arm [17]. The results obtained were subjected to statistical analysis using the Shapiro-Wilk test, which confirmed that the three-sigma rule can be used to calculate the value of the total positioning error of the robot arm. The use of cooperating robotic solutions is also supported by current trend of automation and data exchange in production technologies, the so-called Industry 4.0 [18]. The goal of Industry 4.0 is ultimately to achieve efficiency, reduce costs and increase productivity through integrated automation. In Industry 4.0, production systems are characterized by individualized products in conditions of highly flexible mass production. A literature review of current standards for human-robot collaboration shows they can be used in a wide range of different regimes [19]. The field of application of human robot collaborative systems includes handling, welding, assembly and automotive [20]. Nowadays human robot collaboration systems are widely used in manufacturing companies that operate according to the concept of Industry 4.0. Due to the necessity of meeting the needs of individual customers, interest in the application for knowledge transfer support is growing. [PERSON] et al. [21] provided knowledge related to the interconnection of industrial robotics and productivity of work in small and medium enterprises (SMEs). [PERSON] and [PERSON] [22] developed the knowledge transfer approach is to select the best character istics of a knowledge worker in order to achieve an improvement of effective use of the application for knowledge transfer support among employees. This approach is based on survey and data obtained from Polish production plants. The research so far has mostly focused on positioning accuracy control, research of control systems, control methods and positioning, but we have not been able to find publications aimed at examining the relationship between positioning accuracy of the robotic arm and manufacturing technologies with which it was manufactured. It is from this knowledge that the main research intention of the presented paper is based, the aim of which is to expand the field of knowledge concerning the accuracy of robotic arm positioning in relation to used production technologies. The subject of the paper is the research of production technologies impact on positioning accuracy of a robotic arm. The aim was to find out whether different production technologies (additive and conventional) and the related design differences of the robotic arm affect its operational functionality. In the research, positioning accuracy of a robotic arm formed by three partial arms was specifically investigated, while the first partial arm Arm I was manufactured by two different technologies. On the robotic arm, the research was carried out in such a way that the first partial arm, Arm I, was being continuously changed and was available for research purposes in two variants. Each of the Arm I variants was manufactured using a different technology (additive and conventional) while, at the same time, the individual variants also differed in construction. The design differences of both variants were related to the production technology used. The measurement of positioning accuracy was performed with the use of two methods. Specifically, a contact and a non-contact method were used. The contact method was implemented on a 3D-measuring machine, RAPID, and the second contactless method was performed using an inductive sensor.