# Default Model Description

The Default kinematic model consists of two kinematic chains for the lower body (pelvis and legs) and upper body (torso, arms, and head).

### Upper Body Kinematic Chain

<table><thead><tr><th>Segment</th><th>Parent</th><th width="94">Origin</th><th>Joint</th><th>Proximal</th><th>Distal</th></tr></thead><tbody><tr><td>Torso</td><td>Lab</td><td>Base of neck</td><td>Free joint (6 DOF)</td><td></td><td></td></tr><tr><td>Head</td><td>Torso</td><td>Midpoint of ears</td><td>Free joint (6 DOF)</td><td></td><td></td></tr><tr><td>Right Upper Arm</td><td>Torso</td><td>Right shoulder</td><td>Free joint (6 DOF)</td><td>Right shoulder</td><td>Right elbow</td></tr><tr><td>Right Lower Arm</td><td>Right Upper Arm</td><td>Right elbow</td><td>Two rotational DOF (flexion/extension, pronation/supination)</td><td>Right elbow</td><td>Right wrist</td></tr><tr><td>Right Hand</td><td>Right Lower Arm</td><td>Right wrist</td><td>Two rotational DOF (flexion/extension, ad/abduction)</td><td>Right wrist</td><td>Right mid hand</td></tr><tr><td>Left Upper Arm</td><td>Torso</td><td>Left shoulder</td><td>Free joint (6 DOF)</td><td>Left shoulder</td><td>Left elbow</td></tr><tr><td>Left Lower Arm</td><td>Left Upper Arm</td><td>Left elbow</td><td>Two rotational DOF (flexion/extension, pronation/supination)</td><td>Left elbow</td><td>Left wrist</td></tr><tr><td>Left Hand</td><td>Left Lower Arm</td><td>Left wrist</td><td>Two rotational DOF (flexion/extension, ad/abduction)</td><td>Left wrist</td><td>Left mid hand</td></tr></tbody></table>

***

### Lower Body Kinematic Chain

<table><thead><tr><th>Segment</th><th>Parent</th><th width="74">Origin</th><th>Joint</th><th>Proximal</th><th>Distal</th></tr></thead><tbody><tr><td>Pelvis</td><td>Lab</td><td>Midpoint of pelvis plane</td><td>Free joint (6 DOF)</td><td></td><td></td></tr><tr><td>Right Thigh</td><td>Pelvis</td><td>Right hip</td><td>Three rotational DOF</td><td>Right hip</td><td>Right knee</td></tr><tr><td>Right Shank</td><td>Right Thigh</td><td>Right knee</td><td>Two rotational degrees of freedom (flexion/extension, ad/abduction) or three rotational degrees of freedom (flexion/extension, ad/abduction, internal/external rotation)</td><td>Right knee</td><td>Right ankle</td></tr><tr><td>Right Foot</td><td>Right Shank</td><td>Right ankle</td><td>Free joint (6 DOF), limited translation</td><td>Right ankle</td><td>Right mid foot</td></tr><tr><td>Right Toes</td><td>Right Foot</td><td>Right mid foot</td><td>One rotational DOF (flexion/extension)</td><td>Right mid foot</td><td>Right big toe</td></tr><tr><td>Left Thigh</td><td>Pelvis</td><td>Left hip</td><td>Three rotational DOF</td><td>Left hip</td><td>Left knee</td></tr><tr><td>Left Shank</td><td>Left Thigh</td><td>Left knee</td><td>Two rotational degrees of freedom (flexion/extension, ad/abduction) or three rotational degrees of freedom (flexion/extension, ad/abduction, internal/external rotation)</td><td>Left knee</td><td>Left ankle</td></tr><tr><td>Left Foot</td><td>Left Shank</td><td>Left ankle</td><td>Free joint (6 DOF), limited translation</td><td>Left ankle</td><td>Left mid foot</td></tr><tr><td>Left Toes</td><td>Left Foot</td><td>Left mid foot</td><td>One rotational DOF (flexion/extension)</td><td>Left mid foot</td><td>Left big toe</td></tr></tbody></table>


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