Simulation of trajectory for additive printing of tree-like fractal structure with a six-axis robot

Currently, the widespread use of additive technologies fully raises the issues of creating and implementing optimal bio-inspired designs, because a number of technological restrictions on the geometry and shaping of surfaces are removed. This article presents the results of developing control system algorithms that take into account the operation of an articulated robot as part of technological equipment for multi-axis printing of parts by the fusion deposition method. For non-solid filling of the internal volume of parts, a bio-inspired tree-like structure was chosen, which was formally described using a fractal in the trajectory planning problem. The geometry of the printed object is presented in a cylindrical coordinate system, based on which it is possible to create a layer-by-layer trajectory with a set of concentric circles using a simplified procedure for recalculating coordinates. The results of the work performed are part of a hardware and software complex in a robotic cell for manufacturing parts from PLA and ABS thermoplastics. The trajectory planning is carried out in a simulator, the program code of which is written in the C language and refers to the functions of the Raylib library to perform mathematical operations with vectors, matrices and quaternions. The robot's movement along the planned trajectory is controlled by the STM32H743VIT6 microcontroller with the Free RTOS real-time operating system.

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