Page 178 - Anatomy of a Robot

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ENERGY CONTROL AND SOFTWARE 163
Software interaction
energy API is needed. The software is unaware of power-saving measures, so no
ENERGY AWARE
This is a robot that incorporates one or two of the easier energy-saving tricks. Perhaps
the motors shut down if it’s not moving. Not much time was spent designing the energy
control.
Energy use A few conscious attempts at energy savings are made.
Conservation tactics The computer might use one lower-power state that
enables it to conserve power during its idle loops. The software turns some major
components off when they are not in use.
Method of powering up Generally, both interrupts and application software can
bring the robot quickly back to a full operating state.
Delays The robot powers up very rapidly since all the major software environ-
ments remain loaded in memory. Processing delays are very short.
Special uses The software has few restrictions, so most robot applications can
use this type of energy control if it meets their requirements for conservation.
Software interaction The software has minor API hooks to enable applications
to wake it up and put it to sleep. Since the software environments are always res-
ident, few other API calls are needed.

ENERGY EFFICIENT

This is a robot designed from the ground up to be efficient in its use of energy. The
motors rarely are powered up, the computer only runs when it has to, and all subsys-
tems are designed to use very little power.

Energy use Energy use is greatly minimized. Most energy minimization tech-
niques have been used; only the most difficult ones are left undone.
Conservation tactics The computer makes use of the most aggressive energy-
saving states it can. The software turns all major components off when they are
not in use.
Method of powering up Generally, only interrupts from the timer or outside
stimuli will bring the robot back to a full operating state.
Delays The robot takes a while to power up because many of the major software
environments must be reloaded into memory. Processing delays are not short.
Special uses The software control algorithms must be able to withstand signif-
icant delays because of the sleep state of the processor.