Denavit–Hartenberg parameters

hi,
someone who know DH convention?
it's a 4R manipulator; I have set the frames following DH rules, they should be right
[IMG]http://www.engineersedge.com/engineering-forum/attachment.php?attachmentid=1184&stc=1[/IMG]
is this DH table of parameters rigth?
[TABLE="width: 500"]
[TR]
[TD]Link_i[/TD]
[TD]theta_i[/TD]
[TD]d_i[/TD]
[TD]a_i[/TD]
[TD]alpha_i[/TD]
[/TR]
[TR]
[TD]1[/TD]
[TD]q1[/TD]
[TD]0[/TD]
[TD]L1[/TD]
[TD]0[/TD]
[/TR]
[TR]
[TD]2[/TD]
[TD]q2[/TD]
[TD]0[/TD]
[TD]L2[/TD]
[TD]0[/TD]
[/TR]
[TR]
[TD]3[/TD]
[TD]q3[/TD]
[TD]-M[/TD]
[TD]-N[/TD]
[TD]+90°[/TD]
[/TR]
[TR]
[TD]4[/TD]
[TD]q4[/TD]
[TD]L3[/TD]
[TD]N[/TD]
[TD]0[/TD]
[/TR]
[/TABLE]
thanks

See the following engineering training videos.

[B][URL="http://www.engineersedge.com/video/Denavit-Hartenberg-Reference-Frame-Layout-_v1474"]Denavit-Hartenberg Reference Frame Layout[/URL]

[URL="http://www.engineersedge.com/video/Forward-and-Inverse-Kinematics-Part-1_v1475"]Forward and Inverse Kinematics Part 1[/URL]

[URL="http://www.engineersedge.com/video/Forward-and-Inverse-Kinematics-Part-2_v1478"]Forward and Inverse Kinematics Part 2 [/URL]

[URL="http://www.engineersedge.com/video/Forward-and-Inverse-Kinematics-Part-3_v1477"]Forward and Inverse Kinematics Part 3[/URL]

[/B][ATTACH]1185[/ATTACH]