Pioneer 3™ Operations Manual

Specifications & Controls
Nose
The nose is where we put the onboard PC. The nose is readily removable for access:
Simply remove two screws from underneath the front sonar array. A third screw holds the
nose to the bottom of the AT’s body. The DX nose is hinged at the bottom.
Once the mounting screws are removed, simply pull the nose away from the body. 6 This
provides a quick and easy way to get to the accessory boards and disk drive of the
onboard PC, as well as to the sonar gain adjustment for the front sonar array. The nose
also is an ideal place for you to attach your own custom accessories and sensors.
Access Panels
All DX’s come with a removable right-side panel through which you may install accessory
connectors and controls. A special side panel comes with the onboard PC option, for
example, which provides connectors for a monitor, keyboard, mouse, and 10Base-T
Ethernet, as well as the means to reset and switch power for the onboard computer.
AT’s come with a single access panel in the deck. Fastened down with finger-tight
screws, the User Control Panel and onboard computer controls are accessible beneath
the hinged door.
All models come with an access port near the center of the deck through which to run
cables to the internal components.
SONAR
Natively, ARCOS-based robots
support up to four sonar arrays, each
with up to eight transducers that
provide object detection and range
information for collision avoidance,
features recognition, localization,
and navigation. The sonar positions
in all Pioneer 3 sonar arrays are fixed:
one on each side, and six facing
outward at 20-degree intervals.
Together, fore and aft sonar arrays
provide 360 degrees of nearly
seamless sensing for the platform.
Multiplexed Operation
Figure 14. Pioneer 3 sonar array
Each sonar array’s transducers are multiplexed: Only one disc per array is active at a
time, but all four arrays fire one transducer simultaneously. The sonar ranging acquisition
rate is adjustable, normally set to 25 Hz (40 milliseconds per transducer per array).
Sensitivity ranges from 10 centimeters (six inches) to over four meters, depending on the
ranging rate. You may control the sonar’s firing pattern through software, too; the
default is left-to-right in sequence 0 to 7 for each array. See the ARCOS Chapters 6 and
7 for details.
6 With older Pioneer 2 models, you also needed to remove the Gripper before removing the nose.
With P3 models, the robot’s nose and Gripper come off together, so you only need to remove the
nose mounting screws.
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