Model 1:4 body system Number of bodies:N=4 2 Crank:B1 C-e 方 B2 Link:B2 C2-e2 2 Slider:B3 -e3 C 2 Ground:B4 -e4 Inertial frame: 0-e C3 X3 H1:B4~B1 S1=2 The generalized coordinates H2:B1~B2 S2=2 H3:B2~B3 S3=2 B,:q,=(p,=(x,y9,)Fi=1,…4 H4:B3~B4 S4=2 n=3W=12 Hs:B4~Ground S5 =1 Number of the constraints =,=11 H6:B4~Ground 56=1 Degrees of freedom δ=n-s=1 H7:B4~Ground s7=1[解] Crank：B1 Number of bodies: N=4 Inertial frame： B1 B2 B3 B3 B4 C1 1 x  1 y  C2 2 x  2 y  C3 3 y  3 x  O x  y  C4 4 x  4 y  1 1 e  C  Link：B2 Slider：B3 Ground：B4 2 2 e  C  3 3 e  C  4 4 e  C  e  O  H1：B4  B1 H2：B1  B2 H3：B2  B3 H4：B3  B4 H5：B4  Ground H6：B4  Ground H7：B4  Ground     T T T B : i i i i i i i q  r   x y  i 1,,4 The generalized coordinates n  3N 12 s1  2 s2  2 s4  2 s3  2 s5 1 s6 1 s7 1 Number of the constraints 11 7 1    i i s s Degrees of freedom   n  s 1 Model 1: 4 body system