Mobile robots: the fundamentals
How the machine turns
Differential
Two driven wheels steer by speed difference. Simple, cheap and reliable: forward, reverse, spin on the spot and turn, but no sideways travel. Most jacking models use it.
Dual steer / omni
Steerable drive wheels allow travel in any direction plus spin. In and out of a narrow aisle without reversing, at the cost of complexity and price. Used by omni chassis and heavy omni jacking robots.
Single steer
One steered drive wheel with castors, the classic forklift arrangement. Strong capacity but a large turning radius, so aisles must be wide. All our forklifts use it.
Ackermann
Car-like steering, suited to long bodies travelling straight at speed. The parking robot combines servo drive with both Ackermann and differential models.
Aisle width decides it. Wide enough, and differential or single-steer is the economical answer; too narrow to turn around, and you need omnidirectional.