"Design an innovative body sheath that enables a hands-free version of a knee-to-chest stretch. The product should comfortably wrap around the user's lower back and legs. It requires a mechanism for drawing the knees toward the chest without using hands. Include these views in a technical drawing style: Functional Design View: Illustrate the sheath wrapped around the user's back and over the bent knees, demonstrating how the sheath allows the knees to be drawn towards the chest hands-free. Mechanism Detail View: Focus on the hands-free mechanism – a ratchet system or similar device – showing how it can be activated to tighten the sheath and pull the knees inward. Release Mechanism View: Highlight a release button or hook that allows the sheath to loosen, showcasing how it can be engaged easily by the user. Perspective Use-Case View: Provide a 3D-like perspective view showing the sheath in use in a hands-free stretch position, emphasizing comfort and usability. The drawings should be in a clear, black and white outline format resembling patent illustrations, with solid lines for visible edges and dashed lines for hidden components. Each component should be clearly labeled, indicating materials like durable canvas for the sheath and heavy-duty cord for the tightening mechanism. Include annotations for suggested dimensions and ergonomic features to enhance user experience."