DIGILENT DESIGN CONTEST • DIGILENT DESIGN CONTEST • DIGILENT DESIGN CONTEST • DIGILENT DESIGN CONTEST
The Smart
Shopping Cart
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by Chuan Zhang and Hairong Yan
Embedded Software and System Institute School of Software Engineering
Beijing University of Technology
Beijing, China
This entry in the 2011 Digilent
Design Contest is for a smart
shopping cart system based on
multi-sensor, radio frequency
identification (RFID), visual
identification, and pulse width
modulation (PWM) control. It uses
Digilent’s Nexys2 FPGA board.
Infrared sensors and ultrasonic
sensors provide distance
information. A joystick and wireless
camera in the handle of the cart
enable users to either drive or be
followed by the cart. By using the
RFID tags as an electronic key, the
cart can record the user’s
identification information and accomplish self-checkout. The smart
shopping cart system achieves low power consumption, low cost, and
prolonged operating time.
FIGURE 1.
The smart
shopping
cart.
Why This Project?
A lot of people go to supermarket and have to push a
big bulky cart around. So we thought, “Why can’t we
develop something more intelligent, more interesting, and
more enjoyable to use?”
52 SERVO 02.2012
Hardware Description And
System Theory Overview
We began with a top-down design approach. For each
functional module, we assigned a corresponding IP core. All
data collected from the IP core was then processed in a
Spartan 3E FPGA core. A modular and VHDL code design
enhances the whole system’s real time and reliability
