THB2 8/15/03 12:48 PM Page 51 Displacement y, in Velocity y, ips ¨ Acceleration y, in/sec 2 ¨ 1 FIGURE 2.15. Comparison of basic curves—DRD cam. (Follower has 1/ 2 -in. rise in 150 degrees of cam rotation at 30rpm.) 51