Digital Signal Processing Reference
In-Depth Information
Figure 13.20
FPGA Controlled Toy R/C Truck with IR Distance Sensors
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Seven-Function Controls
When choosing an R/C car, select one that has a remote control with at least
seven remote functions (forward, backward, forward-right, forward-left,
backward-right, backward-left, and stop). Note that these low-cost R/C cars do
not have variable speed or variable turning controls; however, once they are
interfaced to the FPGA board, variable speed and turning can be accomplished
by changing the duty cycle of the command signals. (More on this later.)
A control module built using the FPGAs logic allows a relatively inexpensive
R/C car to perform with the capabilities of the more expensive cars with
“digital proportional steering” and “digital proportional speed controls.” Once
interfaced to the FPGA board, an IP core (Robot_CTL) is used to handle
control of all direction and speed control outputs. As illustrated in Figure 13.21,
the IP core control module affords a higher degree of control than the original
radio control. The outputs connect to the R/C cars internal control circuits that
drive the DC Motors.
