FIGURE 12.
LIDAR unit
from above
showing
drive belt.
44 SERVO 02.2012
FIGURE 11. Clamshell cover removed
revealing LIDAR and circuit board.
addressed the accuracy issue by painting
whatever is in line with the LIDAR with dots
– that is, by pulsing the laser – and then
determining the center of each dot. You
can see this ‘dot spraying’ by turning down
the room lights and recording the NEATO in
operation with your video camera. Most
video cameras are more sensitive to IR than
is the human eye. The LIDAR also
maximizes accuracy by limiting extraneous
light with light filters.
The USB Port
and ROS
This teardown is primarily about
hardware, but I couldn’t resist accessing
the NEATO’s Robot Operating System (ROS)
through the USB port with a type A to
mini-B cable. You can also communicate
with the NEATO via Bluetooth. In short, you
can issue commands to run the motors and
read the sensors without cracking the case.
A built-in help function is available. To
illustrate, let’s set a motor to run in a
particular vector with the SetMotor
command. The format of the command is:
SetMotor
[LWheelDist <LWheelDist_value>]
[RWheelDist <RWheelDist_value>]
[Speed <Speed_value>]
[Accel <Accel_value>]
[RPM <RPM_value>]
[Brush]
[VacuumOn]
[VacuumOff]
[VacuumSpeed <VacuumSpeed_value>]
[RWheelDisable]
[LWheelDisable]
[BrushDisable]
[RWheelEnable]
[LWheelEnable]
[BrushEnable]
As you might expect, Accel is the
desired acceleration in millimeters/
second/second, and VacuumOFF turns off
the vacuum motor.
Once you’ve checked out the built-in
FIGURE 13. LIDAR unit with rotating IR laser
and receiver.
