## 1 Introduction
Moreover, a reduction in complex steps leads to an increase in calibration accuracy. Like most machines and devices, collaborative robotics has limitations, e.g., to achieve the required safety when working by humans, and there are limitations on the load capacity and accessibility of the arms, so they are not suitable for heavy-duty operations. In [7], an overview of the potential uses of collaborative robots in various applications is described. It discusses the sensor devices useful for human detection and activity recognition in industrial environments. The analysis of cobot motion with respect to human proximity has also been addressed by other authors [8; 9]. Collaborative robots are relevant in mixed manufacturing, where small series of highly individualized products are produced. They are ideal for companies that need to automate sub-processes parallel with human work and require agility and flexibility in automating different processes [10; 11]. When designing new devices (prototypes), it is essential to verify the theoretical assumptions. A mathematical model of a real physical system is only as good as its ability to predict what experiments show. In order to have a good model, both its structure, i.e., taking into account all relevant dynamics, and its parameters must be correct. Some model parameters, such as the masses and lengths of the robot segments, can be measured. In contrast, others, such as the temperature-dependent dry and viscous friction, the moments of inertia, or the position of the centre of mass of the segments, are almost always unknown. [PERSON] et al. [12] described a multi-objective design mechanism to minimize the initial and operational costs of industrial robotic links. They investigated the influence of material type and physical dimensions of the robotic link to withstand high loads at critical locations across different frequencies. Based on vibration analysis using FEM, they proposed a design to avoid robot failure at or close to the resonance frequency. [PERSON] et al. [13] investigated the dynamical parameters of a universal robot in two ways, namely, usingMoore-Penrose pseudo-inversion and optimization. Numerical modelling methods, such as the finite element method (FEM), are most commonly used for validation. However, the real operating conditions are sometimes different as they depend not only on the ideal shape of the part but also on other influences such as assembly inaccuracy and manufacturing inaccuracy. These influences can be analysed primarily by using experimental methods. However, there are also many questions here as well, such as what method is appropriate for obtaining a given parameter [14; 15; 16]. Furthermore, applying an experimental method often depends on the feasibility of the experiment itself, the operating range of the measuring instrument and the type of measurement (static/dynamic) [6; 17]. [PERSON] et al. [18] describe a new generation of torque-controlled lightweight robots. In order to operate in unstructured environments and interact with humans, these robots have design features and control/software functions that differentiate them from conventional robots, such as a 1:1 load-to-weight ratio, torque sensing at the joints, active vibration damping and sensitive collision detection, as well as compliant control at the joint and Cartesian plane level. Planning and control robustness with respect to environmental changes is crucial due to the environment's partially unknown properties. The paper presents a methodology for how joint torque sensing (as a crucial property of the robot) is subsequently exploited to achieve the above-mentioned performance, safety, and robustness properties. [PERSON] et al. [19] discussed the possibilities of torque control in space robotics. It involved the development of torque-controlled lightweight robots using all simulation and computational technologies available to approach the technical limits. With 13 active joints integrated into the hand, it was possible to verify strong force grips like soft fingertip grips.