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In view of the many problems in firefighting robots, such as complicated flame positioning, poor environmental adaptability, and difficult installation and debugging, a new firefighting robot design is presented with video full closed-loop feedback to extinguish ground fire in this paper. The firefighting robot consists of a 2-DOF robot, a monocular camera, and a controller. The monocular camera installed on the second link of the robot is utilized to detect and locate ground flames. The robot can dynamically adjust the water landing point to track a flame in real-time through motion control, as the camera is specifically designed with an additional infrared narrowband pass filter and a filter-switching mechanism. An algorithm of detecting and positioning for flame and water landing point is proposed based on image processing and robotic kinematics. Experimental results show that the firefighting robot with video full closed-loop feedback can realize real-time flame detection, location, and sprinkler, and can dynamically track fire location within the monitoring scope. The distance error between fire and the landing point of the water jet can be controlled within a narrow range. Moreover, this firefighting robot is easy to install, debug and have good environment adaptability, and provides efficient and safe solutions for complicated firefighting environment. At the same time, due to its small size and convenient calibration features, this firefighting robot is especially suitable for large space environments.

The stick-slip vibration in deep hard formation is a technical bottleneck restricting the efficient use of PDC bit. In order to combat the stick-slip phenomenon during drilling in deep hard formations, we introduced the high frequency self-excited torkbuster. Based on the analysis of the working principle of the torkbuster, a nonlinear dynamic three-dimensionalmodel of PDC bit is established by using the finite element software (ANSYS/LS-DYNA). The wear conditions and themotioncharacteristicsof the PDC bit as well as the failure of the rock are simulated with and without the action of the high frequency torsional impact, and several field experiments are conducted. The results show that the high frequency torsional impact force generated by the torkbuster can effectively improve the uniformity of the force on the PDC bit and rock, and restrain the stick-slip vibration and the damage of the cutters. The experimental results show that the torkbuster can improve the rock breaking efficiency and shorten the drilling cycle, and provide an important technical reference for the torsional impact technology applying in deep hard formations.

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