Exoskeleton Shoulder Joint That Adapts to Your Arm's Movement

This patent describes a shoulder exoskeleton that uses a special slip mechanism to prevent the robot's joints from getting out of sync with a user's natural arm movements, making it more comfortable and effective.

What it covers

This patent details an exoskeleton system designed for a user's shoulder and arm. It combines a 'spherical parallel manipulator' with a 'passive slip mechanism' (Claim 1). The spherical parallel manipulator uses multiple linear actuators that work together to move the arm, with each actuator's motion depending on the others. The clever part is the slip mechanism, which connects to the user's arm and has a 'passive cuff joint' (Claim 1). This cuff joint allows for both rotational and translational movement, meaning it can slide and twist slightly. For example, if a user's shoulder joint shifts slightly during movement, the internal cuff can translate within an external cuff (Claim 7), preventing the rigid exoskeleton from fighting against the user's natural motion and causing discomfort or mechanical interference.

What it doesn't cover

• —Does not cover exoskeletons that lack a spherical parallel manipulator with interdependent linear actuators.
• —Does not cover exoskeletons where the arm connection mechanism lacks both rotational and translational degrees-of-freedom.
• —Does not cover systems where the slip mechanism is actively controlled rather than passive.
• —Does not cover exoskeletons for other body parts, such as legs or hands, unless they also incorporate a shoulder-like spherical parallel manipulator and slip mechanism.
• —Does not cover a rigid connection between the exoskeleton and the user's arm that does not allow for relative movement.

The clever bit

The truly novel aspect is the integration of a passive slip mechanism, specifically a cuff joint with both rotational and translational freedom, directly into a spherical parallel manipulator-based shoulder exoskeleton. This simple mechanical addition allows the robot to tolerate natural, small shifts in a human joint's center of rotation, which was previously a significant hurdle for rigid exoskeleton designs.

Why it matters

Exoskeletons are powerful tools for rehabilitation and assistance, but a major challenge is ensuring they move naturally with the human body. Misalignment between robot and human joints can cause discomfort, skin irritation, and even injury. This patent addresses a core problem in wearable robotics by allowing the exoskeleton to adapt to the user, making these devices more practical and user-friendly for long-term use in therapy or assistive roles.

Real-world examples

• 1.Rehabilitation exoskeletons for stroke patients
• 2.Assistive exoskeletons for individuals with mobility impairments
• 3.Industrial exoskeletons for heavy lifting or repetitive tasks
• 4.Research prototypes for human-robot interaction