Abstract: A method for evaluating rock drillability by a nano-indentation test on a rock cutting includes: conducting a nano-indentation test on a rock cutting sample, acquiring a displacement-load curve of an indenter, and calculating a micro-hardness under the nano-indentation test; calculating mineral composition of the rock cutting sample based on a statistical distribution characteristic of the micro-hardness, and transforming the micro-hardness under the nano-indentation test on the rock cutting sample into a macro-hardness; and calculating a rock drillability grade characterized by the micro-hardness under the nano-indentation test on the rock cutting sample based on a correlation between the macro-hardness of the rock cutting sample and the rock drillability grade. In the context of few downhole rock samples and high cost, the method overcomes the limitation of sample size and shape on conventional testing and solves the difficult problem of mechanical parameter testing of deep rocks.

Abstract: A monocular camera system for a vehicle includes a front mono camera, a side mono camera, and one or more controllers in electronic communication with the front mono camera and the side mono camera. The one or more controllers execute instructions to determine an ideal lagged distance the vehicle travels between a current time step and a previous time step as two asynchronous camera frames are captured by the front mono camera and the side mono camera, determine a number of delayed frames captured by either the front mono camera or the side mono camera between the current time step and the previous time step based on the ideal lagged distance. The controllers determine a direction of travel of the vehicle that indicates which mono camera is selected to provide a previous camera frame captured at the previous time step.

Abstract: A monocular camera system for a vehicle includes a front mono camera, a side mono camera, and one or more controllers in electronic communication with the front mono camera and the side mono camera. The one or more controllers execute instructions to determine an ideal lagged distance the vehicle travels between a current time step and a previous time step as two asynchronous camera frames are captured by the front mono camera and the side mono camera, determine a number of delayed frames captured by either the front mono camera or the side mono camera between the current time step and the previous time step based on the ideal lagged distance. The controllers determine a direction of travel of the vehicle that indicates which mono camera is selected to provide a previous camera frame captured at the previous time step.