The End Result
Before You Start Animating
The first and most important step is to find good reference video for your animation.
Without reference you would get lost in the process and it would be very difficult to complete the shot.
It is like a blueprint or a plan which helps you to analyze the movement, timings, and makes you clear on how to achieve the desired result.
Make a note of the key poses by drawing them. These are the extreme points of the character in its path of motion. The drawings is just for your understanding so it doesn't need to be perfect.
The character and rig I used for this tutorial is 'Body Mechanics Rig V1.0' by nocemperor and is available for free at Blendswap.com. The model is rigged using Blender's own Rigify system so the controls will be familiar.
Linking and Tweaking the Character
If all the models, environments, characters and animation are created in one file, then it will become messy and complicated to handle. Even if you make different files for each shot, and want to change something about the character model, then you'll have to do it in each file.
It's great to have things separated. The characters and other models must be linked in (similar to import), in a separate file where you animate them.
This way if you make changes in the original character
then those are reflected in all files where the character is linked in.
Only the animation is local and made proxy, and the file will be smaller
in size too.
Open Blender and in a new file, press A to select all objects and then press Del to delete them.
Click on the File menu and select Link, to link in the character model.
Browse for the character file, and click on it.
Within that file there are many folders. Select Group. Usually it is a common practice for modelers and riggers to group the character models and armature.
Finally select the character group. I chose blue.
The character group containing model and armature is now linked into the new file. You cannot edit the character from here, to do so you need to open the original character file.
To animate you must make the armature editable as proxy. Click on the Object menu in the header of the 3D viewport and select Make Proxy...
Select rig_BMR-Blue (the rig or the armature object).
The armature object appears and can be used in pose mode for animation.
With the armature selected, in the header of 3D viewport, select Pose Mode or press Ctrl-P.
Right click on the foot.ik.l bone to select it. In the Properties panel, slide down the value of auto_stretch to 0.00. This will disable the stretching of the leg.
If the bone properties appear under Rig Main Properties panel, then locate the Auto-Stretch IK (foot.ik.l) slider and reduce it to 0.00
Do the same for the other leg. Right click on the foot.ik.r bone to select it and set the auto_stretch to 0.00.
Click on the record button to enable auto-keyframe. This will insert key frames automatically whenever a bone or object is rotated, moved or scaled.
Click on the screen layout button and select Animation.
This layout has necessary windows which are helpful during animation. On the left side is the Dope Sheet where you can see and edit the keyframes of the animation.
Ensure you're on first frame. Press Shift-left arrow to go to frame one. Alternatively you can use the playback buttons in the timeline.
Bring the mouse back on to the 3D viewport. Press A to select all bones. Press Alt-G and then Alt-R to reset the location and rotations of the bone to default.
Since auto-keyframe button is enabled, keyframes are created for the current pose at current frame.
The Dope Sheet is like an explorer pane where you can see keyframes for all objects. But you need to focus only on the armature and its bone, so click on the dropdown list and select Action Editor.
You can rename the action as backflip. Press the F button so that this action is saved in the file. Make sure the Summary button is pressed.
This will bring a summary keyframe on top, marked in orange.
In the 3D viewport, press 1 (numpad) to get into front view. Press 5 (numpad) to toggle off perspective mode. Secondary-click on the arm bones and then press R to rotate them and bring them down.
I'm creating a default starting pose for the character.
Select the finger bones and press S and move the mouse. This will not scale the fingers but will make them curl. Primary-click to confirm. You can rotate them to make them look relaxed.
Press Shift-up arrow to skip 10 frames. You can also drag on the timeline to go to frame number 11.
Press Ctrl-3 (numpad) to get into left view or just 3 (numpad) to get into right view. Secondary-click on the torso bone to select it. Press G and move it down. Primary-click to confirm.
Similarly select and move the arm bones to create the first key pose. Rotate the head bone so that it is looking straight. In the Dope Sheet you'll notice that the keyframes are automatically inserted for the bones, on the current frame.
Press Shift-up arrow again to skip ahead ten frames. In the side view select the bones and rotate or move them to create the next key pose.
Check from the front as well. Press 1 on the numpad to get into front view.
Move ahead ten frames again and create the next keypose by rotating and moving the torso bone and the foot ik bones.
Right now I am focusing only on creating key poses and not the timing. That is why each key pose are in regular gap of ten frames. I'll adjust the timing later.
Similarly create key poses with gap of ten frames. How high the character should be and how much should it go backwards, all should be well referred.
You might need to adjust again and again to achieve realistic flow of motion. To rotate the character use the torso bone and the foot ik bones.
Go to the second last pose where the character touches the ground. Move the mouse in the dope sheet editor and press I to bring the Insert keyframes menu. Select All Channels to insert keyframes for all bones.
I want to have keyframes for all bones at this point so that any further animation will have this point as the default position of all bones.
Move ahead ten frames and make the character stand up straight.
Press Shift-left arrow to go to first frame or use the playback controls.
Press Alt-A to play the animation. Alternatively you can use the play button in the playback controls.
You'll see that the animation is off in timing. But this is to check the path of the motion.
Right now the legs moves before making the jump and the animation needs some in-between frames.
Press Esc to stop the animation. Go to first frame. Secondary-click on the first keyframe of foot.ik.l bone in the Action Editor to select it.
Press Shift-D to make a duplicate and move the mouse so that it is on the 11th frame. Primary-click to confirm.
Ensure the new keyframes is aligned with rest of the keyframes of the 11th frame. Similarly do the same for foot.ik.R.
Drag the timeline to go to frame number 16, i.e. in between 11 and 21. Rotate the arm bones so that they come in front.
Press Alt-A to play the animation. You will see that the feet are better and the arms have a nice swing. Next I will correct the timing.
Secondary-click on the any of the summary keyframe to select it. You'll see that all frames under it are selected. Press G to move it right or left to make them fast or slow.
The closer keyframes are to each other, the faster is the animation. This is a very crucial step so take time to perfect the move. Press Alt-A again and again to preview the timing.
Reduce the end frame to a number closer to last key frame. In the timeline, drag the green line to the frame and press E to make it End frame.
Alternatively you can directly edit and type in the End frame number.
Press Alt-A to play the animation. This was a basic tutorial on character animation. You further refine and tweak to make it much better by adding follow through motions, asymmetry etc.