An Investigation on Speed Control of a Spindle Cluster Driven by Hydraulic Motor: Application to Metal Cutting Machines

Table 6

Experimental results as a function of the oil temperature.

Oil temperature (°C)	Setting speed (rpm)	Results
		Actual speed (rpm)	Overshoot (%)	Delay time (s)	Setting time (s)	Upper bound error (%)	Lower bound error (%)
40(±2)	500	500±10	0	0.02	3.5	2.6	2.8
	900	900±10	0	0.02	3.2	2.2	1.6
50(±2)	500	500±10	0	0.02	3.04	2.6	2.4
	900	900±10	0	0.02	3.25	1.8	1.4
60(±2)	500	500±10	0	0.01	2.57	2.7	2.3
	900	900±10	0	0.01	2.75	1.7	2.4
70(±2)	500	500±10	0	0.01	2.53	2.5	2.4
	900	900±10	0	0.01	2.61	1.8	2.4
80(±2)	500	500±10	0	0.01	2.69	3.6	2.6
	900	900±10	0	0.01	2.07	1.9	2.5