Set Up #4 - Set Driven Key (Foot Roll)

I spoke about what Set Driven Keys did and how they are useful for me for my dissertation, I am now going to talk about how I managed to set up the Foot Roll for animation. For those who didn't read the earlier post, this allows me to create an attribute and then do animations within those created values to help myself (or other animators) make certain animations easier. 

From what I have seen on most rigs, many of them have various attributes created in their channel editor - Toe Bend, Foot Bend to name a few examples. Although in the tutorial I used for the helping me set up the Group Game Character (and the bases of how I managed to get my Character Set Up ready), it only did the one.

So, first thing I did was create an Attribute for the Foot Control (left and right) called the Foot Roll. When the window loaded up, I did the following (Fig 1):

Fig 1: The Set Up for the Foot Roll attribute.

Name: Foot Roll

Keyable

Data Type: Float

Minimum: -10

Maximum: 10

Default: 0

When that was done, clicked okay and it was done. Now I had set up the attribute, I now had to create the Set Driven Key for it.

For this, I would have to select the Foot Control (the curve created in the previous post) and then click Load Driver - as this will be what I select to activate this Driven Key. After that I then selected the Reverse Lock joints I created in the previously and then click Load Driven - reason for this is that these are the joints that are going to be driven when using the Driven Key, these will be what are affected and will then affect the joints that they are parented too (See Fig 2). Simply put, adjusting the value in the driver (Foot Roll Attribute in the Foot Control) will affect the positioning of the driven joints.

Fig 2: Screenshot of the Set Driven Key Window - Foot Control is loaded as the Driver with the Foot Roll Attribute selected, the Reverse Lock: Foot, Toe and Base are loaded in the Driven with Rotate Z being the value.

Now that was set up and ready, it was time to create it. I then clicked Key. From there I set the Foot Roll attribute to 10, and selected the RLFoot joint and rotated that in Z for 22 (Fig 3). 

Fig 3: Foot Joint rotated 22. in Rotate X with the Foot Roll set to 10.

Next was too go back to 5 and select the Toe. Once I hit key, what I essentially did was now that unless the Foot Roll is before 5, the Toe will not move (Fig 4). I then moved the Foot Roll attribute's value to 10 and had the Toe joint rotate in Z for 65° (Fig 5). 

Fig 4: RLToe being designated not to move within Foot Roll when that's before 5.

Fig 5: RLToe being rotated in Z to 65 when Foot Roll is set to 10.

Problem is now that I did that, the foot itself doesn't go into that kind of form, so now I have to go back into the RLFoot and now tweak it slightly. So, I set the Foot Roll to frame 6 and then adjusted the Value in Rotate Z to 12 (Fig 6).

Fig 6: RLFoot set to 12 when Foot Roll is set at 6

Next tweak was going back to 10 in Foot Roll and from then it was a case of keeping the RLFoot more aligned to to the RLToe (Fig 7). Effectively straightening it out a little bit more.

Fig 7: RLFoot rotated in Z at -20 at frame 10.

The final thing left to do now is to have the foot curl in back when it reaches to -10 in the foot roll attribute.

I set the Foot Roll attribute to -10, and then rotated it in Z for a value of 35 (Fig 8).

Fig 8: The final stage for setting up the Foot Roll. Selecting the RLBase and then rotating the base in Z for a value of 35.

And that is how I set up the Set Driven Key for the Feet. I did this post for only one of the feet, but the process is exactly the same. 

Next post will talk about how I got the back of the rig set up.