Leonardo da Vinci is usually credited with conducting the first systematic study of friction in the late 15th century, a subfield now known as tribology that deals with the dynamics of interacting surfaces in relative motion. Da Vinci's notebooks depict how he pulled rows of blocks using weights and pulleys, an approach that is still used in frictional studies today, as well as examining the friction produced in screw threads, wheels, and axles. The authors of this latest paper used an experimental setup similar to da Vinci's.
真要拿这套方案去赌消费者是否认可，还是要看最后的路测报告，否则很难服众。
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Isaacman said SpaceX and Blue Origin are "both looking to do uncrewed landing demonstrations as part of the existing agreement."