GEERHEAD
USB using integrated Wi-Fi communications,” according to
NI. The robot uses its sensors to track a predefined area
that it must remain in to receive possible transmissions from
an operator using teleoperation.
This robot makes good use of the LabVIEW embedded
module for ARM microcontrollers. This LabVIEW component
is useful for routing and interpreting sensor data, making
decisions, controlling motors or actuators, moving solar
panels for optimum light exposure, controlling Wi-Fi, and it
uses an LCD display to report the robot’s status and the
amount of light hitting the solar panel.
A servo controls the angle of the panel which is the
battery’s only means of recharging. An H-bridge (from
Personalize par transistors) alters current polarity to rotate
the motors forward and backward.
Accurate estimates and controls around power usage
are crucial to making the robot autonomous; this gives it
enough power to use all its technologies and perform all its
tasks on its own without running out of energy. The H-bridge controls the current to the motors to prevent spikes
which could occur during motor activation and could drain
too much power. To take some load off the battery, two
regulators step the battery voltage down for the ARM
processor board and the wireless router which each require
5V. Ultimately, a larger solar panel can be added.
NIRo
NIRo
from the
opposite
angle.
NIRo is a small UGV programmed by LabVIEW Real-Time and FPGA Modules, and built on the Single-Board RIO
embedded platform using off-the-shelf components
exclusively. The robot applies three infrared sensors and two
ultra-sonic sensors for object avoidance and navigation.
The robot’s embedded controller (sbRIO-9632)
manages its sensor data, motor control, and intelligence.
The infrared sensors (Sharp GP2D12) detect objects via
distance calculations based on the time it takes for the
infrared light to reflect back to the sensor.
The robot’s ultrasonic sensors (Devantech SRF05) detect
objects based on the time it takes sound to return to the
sensors. The robot uses an H-bridge (Solutions Cubed) to
move current to the motors from the battery.
All the robot’s communications and networking are
internal, with the robot only operating in an autonomous
mode. First, the robot’s controller manages obstacle
avoidance tasks. “The obstacle avoidance algorithm uses
See the H-bridges up top, the Single-Board
RIO below, the IR sensor to the left of the
tread, and two pairs of ultrasonic sensors
out front.
This is an iteration of the NIRo robot — an in-house demonstration platform
built by NI engineers. The robot showcases what roboticists can do with
the platform using off-the-shelf components from a local hobby store.
Engineers based the UGV (Unmanned Ground Vehicle)
on the Single-Board RIO embedded platform.
SERVO 08.2010 11
