AGV Caster Wheels as Part of the Chassis Mechanical System

In professional AGV and AMR design, an AGV caster wheel is not merely a passive support component.
From an engineering perspective, it directly participates in the mechanical and kinematic behavior of the chassis.

Proper caster design affects:

• Load distribution

• Normal force on drive wheels

• Steering resistance torque

• Motion control accuracy

Load Distribution and Mechanical Balance

In a typical 2-drive + 2-caster configuration, insufficient caster stiffness or poor mounting accuracy will cause load concentration on the drive wheels.

This results in:

• Increased rolling resistance

• Higher continuous motor torque

• Reduced gearbox and bearing lifetime

Best practice:
Drive wheels should carry 45%–55% of total vehicle weight.

Kinematic Influence During Steering

Swivel caster wheels introduce scrub torque during rotation, especially in zero-radius turns.

Poorly selected casters may cause:

• Abnormally high turning current

• Low-speed vibration

• SLAM positioning deviation in AMRs

Key influencing factors:

• Wheel diameter

• Offset distance

• Tread friction coefficient

Engineering-Level Selection Parameters

Coordination with Servo Drive Wheels

Mismatch between caster wheels and servo drive wheels may lead to:

• Control compensation overload

• Encoder-based odometry error

• Motion instability at low speed

Design rules:

• Diameter difference within ±5%

• Unified tread materials

• Controlled swivel damping for precision AMRs