Pallets are used in a variety of automated
and semi-automated parking systems. Like a car-sized plate, the pros and cons
of pallets have been debated for decades. The current trend toward pallet-less
systems may be a bad idea if the alternatives create more problems. We’ll
explain as we look at some of the pros and cons of pallets.
First off, we should make clear that a car-parking
pallet is a flat, movable structure for a car to sit upon as it is transported
and parked within some type of parking system. The car remains on the pallet
until it leaves the car system.
The
Pros
Since cars aren’t designed to be moved
without a driver or lifted, the car parking pallet simplifies the transport of
a car within a parking system. The car’s tires rest on the pallet and all
mechanical transport apparatus interface with the pallet. This minimizes the
complexity of transport mechanisms since no accommodations for car size
(wheelbase, width, ground clearance, etc.) are required. It also means that no
equipment such as robotic or other lifting mechanisms touch the car.
Moreover, car-parking pallets may provide
some maintenance and environmental benefits. Parked cars drip, leak and drop
all types of liquids and solids from rainwater, snow, coolants and lubricants to
road dirt, sand, salt and debris. Capturing these materials on the pallet can
reduce clean up within the parking system. If the materials collected on the pallets
are disposed of properly, then the parking system prevents them from entering
the environment.
The
Cons
One downside of car-parking pallets is the
logistics: moving and storing empty pallets. For example, when two cars
sequentially enter a parking system, an empty pallet must be located and moved
into place to pick up the second car for parking. What do you do with empty
pallets when they aren’t in use? Regardless the answer, there is very likely
some loss of efficiency due to the movement and storage of empty pallets.
Furthermore, pallets are typically sized to
accommodate the largest possible vehicle since the logistical challenge of
using two sizes of pallets is considerable. This leads to all parking spaces
being the same size as the pallet. Parking subcompact cars in spaces designed
for full-size cars isn’t as space efficient as having parking spaces for
different car sizes. Car-parking pallets are not weightless.
This means an increase in the energy used to transport cars.
The arguments for and against car-parking
pallets are complex since they are integral to such important factors as speed,
space and energy efficiency, maintenance and reliability. Intuitively,
eliminating pallets seems advantageous. However, slow, delicate and
high-maintenance robotic transport systems may be less capable and less
reliable than using pallets. The bottom line is that automated parking systems
transport designs, with or without pallets, should be thoroughly evaluated.