Page 179 - Anatomy of a Robot

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164 CHAPTER SEVEN
Software interaction
The software has a significant number of API hooks to
enable applications to store and retrieve environments, wake up the processor, and
put it to sleep. The API generally has hooks for both the boot Read-Only Memory
(ROM) and the application software.
ENERGY MISER
This is a robot that uses the bare minimum amount of energy to accomplish its tasks.
The best examples of this are space-traveling robots, optimized for solar power and the
conservation of energy. Mobile robots often have a similar design, especially if they
operate unattended.

Energy use Energy is completely minimized.
Conservation tactics Every subsystem is turned off when not in use. The bat-
teries have very long lifetimes and the robot will not drain them if left immobile.
The computer makes use of the most aggressive energy-saving states that it can.
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 quite a while to power up because all the major software
environments must be reloaded into memory. Processing delays may be significant.
Special uses Generally, the application must be able to tolerate significant
delays on the part of the computer control system. This tends to restrict the use of
such drastic energy-saving methods to specialized situations such as handheld sys-
tems and unattended robots.
Software interaction The software has a significant number of API hooks that
enable one or more deep-sleep energy states. Most of the application code must
be specially written in light of it.

Hardware Considerations

Nothing but hardware can use energy. Software cannot use energy directly without
commanding hardware to do to. The hardware itself must be well constructed so as to
not waste energy.

POWER SUPPLY
Certainly, the power supply is a very important place to start when trying to save energy.
In fact, any heatsink in the robot is a prime place to try to save energy. Energy wasted