6Sirjacobs D. On-line soil mechanical resistance mapping and correlation with soil physical properties for precision agriculture[ J]. Soil & Tillage Research, 2002, 64:231-242.
7Suleyman Yaldiz. A dynamometer design for measurement the cutting forces on turning[ J]. Measurement, 2006, 39: 80-89.
8Seker U, Kurt A, Cifici I. Design and construction of a dynamometer for measurement of cutting forces during machining with linear motion[ J]. Mater Des, 2002, 23: 355- 360.
