---

Considering frictional, inertial and machining forces, the authors have presented an enhanced analysis of a hexapod table as used in milling machines. The Newton-Euler analysis of hexapod’s components has been implemented by a simulation program developed by the authors in MATLAB environment and the results have been verified by those of others. The impact of various loads involved in machining operation carried out on a milling machine equipped with hexapod table has been presented in the paper. This provides a potential machine tool designer with guidelines on the importance of these loads and helps him give appropriate weights to them.

---

This paper is seeking to add a CNC G-code to hexapod CNC system. The mentioned G-code is five axis tool radius compensation. Once the tool radius is changed, especially in the case of tool size changing with tool wear in machining, a new NC program has to be recreated. Five axis tool radius compensation correct cutter path automatically. This G-code contains all the main parts of a standard code such as: interpreter, interpolator and inverse kinematics unit. The interpreter unit extracts the position and orientation from the received code and sends it to the interpolation and kinematics units to correct the errors and achieve the desired six pods lengths. In the tool radius compensation algorithm, the unique vector of the movement direction of the tool tip and the normal vector of the machining surface have been used to calculate the direction of the tool radius compensation. The offset path is calculated by offsetting the tool path along the direction of the offset vector. Accuracy of the proposed method tested with a number of experiments. The experimental results confirmed the accuracy of the proposed methods.

---

The present article deals with analytical modeling of boring bar dynamics as well as identification of unknown parameters for the dynamic model. Experimental modal analysis is utilized to measure the Frequency Response Functions (FRFs) of cutting tool. Using the analytical methods of modal analysis theory, dynamic parameters of boring bar (i.e. natural frequencies, damping ratios and modeshapes) are extracted from curve fitting of experimental FRFs. A new physical configuration is proposed, in order to accurately estimate the dynamic response of boring bar in time/frequency domains. In the proposed dynamic model, boring bar is modeled as an Euler-Bernoulli beam with flexible support and tip mass. The mechanical properties (i.e. modulus of elasticity and density) are considered to be constant along beam length. The flexibility of boring bar's clamping interface is modeled by linear translational/torsional spring elements. Particle Swarm Optimization (PSO) is utilized to identify the unknown parameters of dynamic model. The parameters include translational/rotational clamping stiffness and dimensionless correction factors for boring bar's diameter/tip mass. These parameters directly control the mass/stiffness distribution of proposed dynamic model. The FRFs obtained from updated model of boring bar are compared with experimental FRFs. It is shown that, by optimal selection of unknown parameters, boring bar FRFs can be accurately calculated at any point along its length. Hence, by incorporating the dynamic model of passive/active actuator into the proposed dynamic model, the stability lobes of dampened boring bars can be predicted.

---

The course of change and transformation of the generations of shipyards shows that the occurrence of an accident or the invention of new technology and advanced machine tools has caused the shipyard to change to the next generation every period. This generation change includes 5 levels so far. The difference between generations of shipyards includes three general parameters of production philosophy, production technology and factory layout. The realization and development of the first generation in the late 1940s, the second generation in the late 1960s, the third generation in the late 1980s, the realization and development of the fourth generation in the early 2000s, and the development of the fifth generation started in 2020. The most important factor in the change of generations of shipbuilding is to achieve the open index (better, cheaoer and sooner). In the research, an overview of important parameters in determining the generation of shipbuilding with advanced machine tools, such as material flow, pre-outfit workshop, block making, factory expansion, mechanization, buffer area, process line, outfitting, and vessel dimensions, have been discussed. 

---

In this research, errors and accuracy of a 5-axis machine tools are investigated using a balbar device. The focus is on the measurement of positional errors and rotational errors related to rotational axes. Therefore, first, using homogeneous transformation matrices and based on the kinematic chain of machine axes, a mathematical error modeling is done for each axis in order to get an overview of the impact of errors on machine operation. In the following, a method to measure these errors is proposed, and to validate this proposed method, its results are compared with a valid method. Homogeneous transformation matrices (HTMs) are used to create a machine tool model and generate bearing error diagrams due to machine tool geometric errors based on the given experimental design. Simulated payload trajectory patterns can be used to evaluate unique fault effects for detected faults and to diagnose machine tool conditions.

---

The third national conference on advanced machine tools and machine tools was held in Arak University on October 26, 1402, in order to specialize Iran's manufacturing and production engineering meetings. This conference was held with the slogan "Machine tools, the driving force of production" in the year named "Production Growth and Inflation Control". In this conference, researchers working in the field of machining and machine tools exchanged their scientific and practical achievements. This conference was hosted by Arak University as the mother university of the central province with the cooperation of professors from other universities of the country and industrialists of the country's related industries, including the aviation and marine industries of the Ministry of Defense and the Educational and Research Institute of the Ministry of Defense, in person and virtually.