C h a p t e r 3
As the name suggests, AMRs are mobile
devices. To this end, AMRs are powered
by batteries and rely on energy-efficient
power architectures to support sustained
operation with minimal downtime. Because
these systems operate untethered, energy
availability is constrained by battery
capacity, and every subsystem must
be optimized to extend runtime without
compromising performance. Intelligent
power management is therefore central to
AMR design.
The foundation of energy efficiency
begins with how power is drawn from and
distributed across the system. AMRs
typically operate on multi-cell lithium-
ion battery packs. For smaller AMRs, this
can be in the 10-cell range, with nominal
voltages of 36- 40V, while larger Mobile
Robots operate from 60V or 80V.
As the battery discharges, onboard power
systems must accommodate a wide input
range while maintaining tight regulation
for critical subsystems. This includes
stepping down voltage levels to support
20V motor drivers, 5V control electronics,
3.3V sensors, and 1.8V processors. High-
efficiency DC-DC converters minimize
losses during this voltage conversion
process and help maintain thermal
stability in compact enclosures.
INTELLIGENT POWER AND
ENERGY EFFICIENCY
Designers must ensure motor
control is extremely efficient by
using low-loss switches—with low
RDS(on), low gate charge, and high
switching efficiency—to minimize
wasted power, thereby maximizing
Li-ion battery life."
Bob Card
Americas Marketing Manager, Analog Mixed Signal Group,
onsemi
15
Engineering the Future: The Sensors and Systems Powering Modern Mobile Robots
