compass gait model

Compass Gait Model, also known as the Four-Link Compass Model or simply Compass Model, is a simplified representation of human walking and gait analysis used in robotics and biomechanics. It is a four-bar linkage system that mimics the basic movement patterns found in human locomotion. The model consists of four links, typically labeled as stance leg, swing leg, pelvis, and trunk, interconnected by joints.

1. **Stance Leg**: Represents the lower limb on the ground, supporting the body weight.
2. **Swing Leg**: The leg that is not in contact with the ground, preparing to swing forward during the gait cycle.
3. **Pelvis**: Acts as a pivot point for hip rotation and serves as the connection between the stance and swing legs.
4. **Trunk**: The upper body, which rotates around the pelvis joint to maintain balance and forward progression.

The key characteristic of this model is that it exhibits bilateral symmetry, meaning it can move independently on both sides while maintaining a forward progression. It is often used to study gait transitions, such as heel strike to toe-off, and analyze how various factors like joint angles, muscle forces, or external loads affect the efficiency and stability of walking.