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This study aims to propose a calibration method to enhance the positioning accuracy in dual-robot collaborative operations, aiming to address the challenge of drilling hole spacing errors in spacecraft core cabin brackets that require an accuracy of less than 0.5 mm.

Initially, the cooperative error of dual robots is defined. Subsequently, an integrated model is constructed that encompasses the kinematic model errors of the dual robots, as well as the establishment errors of the base and tool frames. A calibration method for optimizing the cooperative accuracy of dual robots is proposed.

The application of the proposed method satisfies the collaborative drilling requirements for the spacecraft core cabin. The average cooperative positioning error of the dual robots was reduced from 0.507 to 0.156 mm, with the maximum value and standard deviation decreasing from 1.020 and 0.202 mm to 0.603 and 0.097 mm, respectively. Drilling experiments conducted on a core cabin simulator demonstrated that after calibration, the maximum hole spacing error was reduced from 1.219 to 0.403 mm, with all spacing errors falling below the 0.5 mm threshold, thus meeting the requirements.

This paper addresses the drilling accuracy requirements for spacecraft core cabins by using a calibration method to reduce the cooperative error of dual robots. The algorithm has been validated through experiments using ER 220 robots, confirming its effectiveness in fulfilling the drilling task requirements.

Aerospace assembly demands high drilling position accuracy for fastener holes. Hole position error correction is a key issue to meet the required hole position accuracy. This paper aims to propose a combined hole position error correction method to achieve high positioning accuracy.

The bilinear interpolation surface function based on the shape of the aerospace structure is capable of dealing with position error of non-gravity deformation. A gravity deformation model is developed based on mechanics theory to efficiently correct deformation error caused by gravity. Moreover, three solution strategies of the average, least-squares and genetic optimization algorithms are used to solve the coefficients in the gravity deformation model to further improve position accuracy and efficiency.

Experimental validation shows that the combined position error correction method proposed in this paper significantly reduces the position errors of fastener holes from 1.106 to 0.123 mm. The total position error is reduced by 43.49% compared with the traditional mechanics theory method.

The position error correlation method could reach an accuracy of millimeter or submillimeter scale, which may not satisfy higher precision.

The proposed position error correction method has been integrated into the automatic drilling machine to ensure the drilling position accuracy.

The proposed position error method could promote the wide application of automatic drilling and riveting machining system in aerospace industry.

A combined position error correction method and the complete roadmap for error compensation are proposed. The position accuracy of fastener holes is reduced stably below 0.2 mm, which can fulfill the requirements of aero-structural assembly.

The purpose of this paper is to obtain high-performance ceramics and enrich additive manufacturing of ceramic parts. Also, a new manufacturing technique based on slurry by selective laser melting (SLM) was studied, which has some significant advantages compared to indirect selective laser sintering of ceramic powders.

To study the effect of laser parameters on the surface morphology and melting state of pure Al₂O₃ ceramics, laser power varied between 100 and 200 W and scan speed varied between 60 and 90 mm/s.

Experimental results show that Al₂O₃ slurry melts completely when the laser power is about 200 W and the scanning speed is 90 mm/s. Surface quality cannot be improved effectively by changing the scanning speed. However, surface quality improves when the laser power is 200∼205 W and energy density is 889∼911 J/mm³. Thermocapillary convection was observed during SLM. By changing the temperature gradient, streak convection and flowing Bénard cells were obtained during SLM of Al₂O₃ slurry.

It is feasible to produce slurry ceramic parts without binders through SLM. Increasing the laser power is the most effective way to fully melt the ceramics. Complex thermocapillary convection was observed during this new process; it may be used to produce crystals.