How do I choose the right reach for a robotic arm?
Choose reach by measuring the positions the tool must access from the intended mounting location. Include every pick point, destination, approach path, and tool orientation. Maximum reach describes a geometric limit, while useful reach depends on whether the robot can perform the task with adequate clearance and suitable joint positions.
What this means in practice
Tool length can move the working point farther from the wrist, but it also changes load distribution and may increase interference. Selecting the longest available arm is not always the best solution. A larger arm may require more space or a different mounting structure, while moving a fixture can solve a reach problem more efficiently.
Avoid designing around maximum extension
A long reach specification can be misleading when the task needs a particular wrist angle or access inside a machine. The tool may reach the endpoint while the elbow or wrist lacks clearance. Nearer points can also be awkward if the arm must fold into a restricted area.
Compare alternative base positions before increasing robot size. Moving the arm or rearranging a fixture may improve access and reduce travel. Verify both extremes of the process and the intermediate path, including how a loaded tool retreats from the workstation.
Key points
Measure the farthest and nearest required targets.
Check vertical access and the orientation required at each station.
Include the carried part, surrounding obstacles, and recovery positions.
Practical example and next step
Build a scaled layout before ordering. Test the full cycle with the proposed tool and avoid relying on operation at the edge of the envelope. Leave room for product variation and future fixture changes without compromising the validated operating arrangement.