Linear Motion System Selection Criteria | P.O.S.T.L.U.D.E.S.

When choosing Linear Motion Systems, it's important to consider several factors for your application. The acronym P.O.S.T.L.U.D.E.S can help you ask the essential questions to identify the best product.

P — Precision

• What is more important, accuracy or repeatability?
• What is the accuracy/repeatability requirement?
• Are these values realistic, based upon the desired motion profile?

O — Orientation

• How will the system be mounted? (“normal”, on its side, inverted, vertical, at an angle, etc.)
• How will this affect the load requirements?

S — Speed

• What is the maximum speed and acceleration required?
• What is the maximum jerk allowable?
• What motion profile (shape) is desired?

T — Travel

• What is the required travel (stroke)?
• What is the overall envelope allowed?
• How much over-travel (safety zone) is required?

L — Load

• What is End of Arm Tooling (EOAT) and where is it located?
• What additional forces are seen by the system during use (e.g., cutting or pushing forces)?
• What do the static and dynamic free body diagrams look like? Have all loads been accounted for?
• What is expected of the system after an impact?

U — Unknown

• What are the known unknowns? What is a reasonable value for these unknowns?
• How will someone misuse this system?
• What could possibly go wrong?
• What else could go wrong? (Repeat this question until you can’t think of anything else!)

D — Duty Cycle

• What is the actual duty cycle for the system?
• What is the expected lifetime?

E — Environment

• In what environment will the system be installed?
• Are there any hazards in the environment?
• What is the maintenance schedule, and is the system accessible for maintenance/lubrication?
• Are there contaminants in the environment which can damage the motion system?
• Will the system disburse contaminants into the environment that could damage other equipment or products

S — Safety

• Are there any safety standards to which this system needs to conform?
• What could happen if the system fails?
• Are there safeguards that need to be installed for a system failure?
• Could people be injured by this system? If so, how will the system be protected?