Reachopening

Reachopening is a term used in robotics and automation to describe the minimum opening, gap, or aperture that a robotic system’s end-effector must pass through to reach a target location within an environment. It accounts for the size and orientation of the opening, the geometry of the robot, and any obstacles present. The concept is commonly employed in motion planning to ensure that a planned path remains feasible through constricted passages.

In practice, reachopening is evaluated in configuration space by considering how the robot’s geometry interacts with the opening as it moves. It can be expressed as a width, height, or diameter of a passage, or as a set of angular clearance requirements, depending on how the robot must orient itself to pass. Reachopening measurements are often determined through collision checking, kinematic modeling, and sometimes optimization or sampling-based planning to identify the smallest passage that still allows a feasible trajectory.

Applications of reachopening include tight-space manipulation on assembly lines, robotic systems operating within constrained enclosures or conduits, and medical robotics where tools must pass through narrow channels such as endoscopes or surgical ports. It is also relevant in aerospace assembly, warehouse automation, and any scenario where robotic reach must be validated against physical constraints.

Related concepts include clearance, passability, and reachability analysis. While the term appears in literature and toolkits dealing with constrained motion planning, there is no universally standardized definition, and the exact formulation of reachopening can vary by context and hardware.