Such mounting is far stronger than you might imagine
(especially if you glue one or two wood strips around the
edges of the motors as shown), yet the motors can be
removed to be used in future projects.
You can also see in the figure how to build a simple
“caster” which is needed on two-wheeled robots. It was
made from a short piece of wooden dowel tipped with a
chair leg slide (shown in Figure 6), but a block of foam
board could easily substitute for the dowel.
With the motors mounted, we can turn to the
electronics, which are built on a solderless breadboard.
Figure 7 shows small strips of wood glued to the top of the
DC robot chassis. Figure 8 shows how these blocks hold the
battery and breadboard in place. Figure 9 shows the
schematic for the physical circuit built on the breadboard.
Notice how few components are required. The two DC
motors can connect directly to the RROS chip because it
contains the necessary H-bridge circuitry for driving motors,
as well as the low-level code for controlling them.
A Bluetooth transceiver provides the communication
link to the PC running RobotBASIC. A regulator provides the
five volt power needed for the transceiver and for other
devices to be added later. The buzzer is not required, but
having audible feedback when the robot is turned on,
initialized, etc., can be comforting.
Making the Robot Move
With the hardware complete, let’s see how easy it is to
make the robot move. Look at the program in Figure 10.
The first two lines of code use an include file (provided by
RobotBASIC) to set up a lot of constants that make it easier
56 SERVO 12.2017