Design of attitude monitoring system for directional drilling continuous coring tools

Directional drilling continuous coring, as an emerging geological exploration technique, holds vast potential in the field of mineral resource exploration. To facilitate the development of directional continuous coring tools with proprietary intellectual property rights, an attitude monitoring system based on attitude sensing and wireless communication technology was designed in this paper. Concerning the hardware system design, the MPU9250 attitude sensor and STM32F103C8T6 main control chip were adopted to monitor the attitude change of drilling tools, where the communication through geological layers was achieved using a LoRa wireless module. Additionally, to accommodate the structural of the drilling tool and the requirements of measurement while drilling, a downsized system circuit was autonomously designed, which is sized 70 mm × 25 mm × 7 mm (L × W × H). In terms of software design, data collected by MPU9250 was processed by complementary filtering and Kalman filtering. Besides, an error compensation model for solution of drilling tool attitude was established, and an upper computer was designed to exhibit the real-time attitude of a drilling tool. Ultimately, the reliability and accuracy of both hardware and software were verified through simulation tests under the environment with strong electromagnetic interference. The outcomes reveal that the designed system effectively mitigates the drift, cumulative errors, and noise in the inertial sensing components, capable of achieving the continuous and stable real-time attitude monitoring of drilling tool, thereby offering a novel approach towards achieving the attitude monitoring in directional drilling continuous coring tools.