Tutorials

Why?

Every now and then I get stuck in my progress and so I have to spend time figuring out how in the hell I am going to do what I set out to do.

This page I plan to use to provide answers to the questions I have been asking and antagonising over. I hope people find this page helpful.

Tutorials 

 Vehicle Tutorials

I would just like to add a brief bibliography of tutorials which have helped me with my own work:

YouTube's 3D Joe, has offered many tutorial videos which in whole are very intuitive and easy to follow. His tutorials on rigging vehicles are very useful and so I have followed instruction and modified his tutorials to suit my own needs and design my own systems.
http://www.youtube.com/user/3dimensionalJoe

Motorcycles

Suspension

Front Forks (Dual Motion)

As you may or may not have seen, I modelled a Monster Trike in the theme of "The Punisher". As a Game Artist I figured I needed to know how to "animate" such a model so it could be used inside a game for gamers to use or look at.

All was well until I hit a snag with the Front Forks suspension. I had chosen a design which allowed the axle to pivot off-set from the main front forks whilst still allowing conventional bike suspension up/down travel.

The main problem being that I couldn't get the steering AND the suspension to work at the same time. This led to ages of trawling the internet for ANYONE who had solved my problem to no avail and so I worked it out and below are the steps to achieve dual suspension.

 The End Result

1. Before you start
2. Separate your front wheel into the different parts

>>a.       Part1: Handlebars, Front forks, Top of suspension.

>>b.      Part2: Moving part of suspension

>>c.       Part3: Wheel

>>d.      (optional depending on design) Part3: Axle (if off-set) otherwise include with part 1

Motorcycle Front Forks Suspension 

3. Create a Dummy called “Wheel” & align to the front wheel 

4.With the “Wheel” Dummy selected, select the scale tool, then hold SHIFT too copy & reduce Dummy insize. Rename this Dummy “Steering” 

5.       Then create a smaller Dummy using the steps described above and call the new Dummy “Hub” 

6.       Align all 3 to the front wheel 

7.       Link Wheel mesh to Wheel Dummy. 

8.       Link Wheel Dummy to Steering Dummy. 

9.       Link Steering Dummy to Front wheel axle MESH.

Suspension 

10. Align the Pivot of the Axle MESH to where it joins the front forks MESH.

11.  Create 2 suspension Dummys one above called “Anchor” & one below called “Travel”

 

12. Create a line “Anchor” & align it to the suspension anchor (the upper point where the suspension attaches to the bike)

13. Copy the “Anchor” line to create a second line called “Travel” and position it to the Moving Suspension piece “in line” with the “Anchor” line. 

 

14. Center the pivots of each line.

15. Align the “Anchor” Dummy to the “Anchor” Line then “Constrain to Path” and Select the “Anchor” Line.

16. Turn off loop in the Motion panel

17. Align the “Travel” Dummy to the “Travel” Line then “Constrain to Path” and Select the “Travel” Line.

18.Turn off loop in the Motion panel

19. Select the Anchor Dummy, assign a float expression with the Anchor Travel as controller.

20. Link Suspension

21. Link “Anchor” Line to “Handlebars”

22. Link “Travel” Line to “Handlebars

23. Link “Anchor” Dummy to “Handlebars” MESH

24. Link “Moving Suspension” MESH to “Anchor” Dummy

25. Link “Travel” Dummy to “Moving Suspension” MESH

26. Link “Hub” Dummy to “Travel” Dummy

Suspension Test – Grab Travel Dummy then Move up and down to test moving suspension

27. Steering 

28. Create a Dummy called “Axle Pivot” 

29. Align the “Axle Pivot” Dummy to the “Axle” MESH 

30. Link “Axle Pivot” Dummy to “Handlebars” MESH” 

31. Select the “Axle” MESH then select “LookAt Constraint” and then select the “Hub” Dummy.  

NOTE #1: I had a couple of problems with this after I reset everything to create this step-by-step. If you are receiving a message about being unable to complete the “LookAt Constraint” select the “Rotation” transform in the “Motion Panel>Assign Controller” section, then open the “controller” menu and select the default “Euler XYZ” which should reset the rotation transform allowing you to use the “LookAt Constraint” (this approach should work with the “Position” transform too)

NOTE #2: Once you enable the “LookAt” Constraint you may notice the orientation of the suspension changes, to reset this to original position; in the Motion put a check in the box marked “Keep Initial Offset”

32. Select the “Axle” then select “Position Constraint” and then select the “Axle Pivot” Dummy.

  

As above - Suspension Test: Grab the "Travel" Dummy & Move that up & down

As above - Steering & Suspension Test: For the Steering: Grab the steering Dummy and rotate left or right

(Most important test to see if everything "stays together" when moving the handlebars. Then test suspension once handlebars have been turned to check suspension still works.

Closing Notes (Troubleshooting)

Ok, these should be the steps required to achieve a result similar to the one shown to the left where the entire forks system turn but at the same time allow a dual movement of suspension moving the axle and the forks suspension as the wheel moves up and down over bumps.

However this is not necessarily the case, I’ve found varying results upon completion of the above steps; mainly when turning the steering wheel I find the Wheelhub often doesn’t connect properly to the handlebars resulting in a separate rotation. 

To fix this I found that looking at the schematic view to make sure everything was connecting properly. Often I found that the set up was right but for some reason it didn’t work, so I detached and reset the parts that didn’t work properly and then re-attaching/constraining etc.

I fear though that maybe I’m too close to the problem, I’d be grateful that if anyone found this useful enough to try building a similar suspension system that they could leave a comment to tell me where I went wrong and make this more accurate.