Liter
Liquid Tending Robot
Julie Lam
Kevin Chang
Jason Smith
Andrew Jenkins
Overview
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Introduction, Purpose,
and Features
Block Diagram
Microcontroller
FPGA
Peripheral Interfaces
Power Supply
Timeline
Risks and Contingency
Plan
Purpose
 Proposed
project is an interesting
prototype.
 Dispensing chemicals not
safe/desireable for human interaction.
 Dispensing in an environment
dangerous to human operators.
Objectives
 Move
Core
Goals
Extensions
using tracks and motor
 Receive order by using Keypad and
LCD
 Delivering an assortment of drink
through controlled valves
 Read customer information (tab, name,
preferences) through magstripe reader.
 Follow route using sensors.
 Pre-recorded voice prompts.
Block Diagram
SRAM
LCD
Keypad
Path
Sensor
Microcontroller
ROM
Audio Out
FPGA
Registers
Interrupts
A/D
Motors
Power
Supply
24V
110VAC
Card
Reader
12V
5V
5V Analog
Valve
Solenoids
Microcontroller
Jason Smith
SRAM
Peripherals
Microcontroller
ROM
A/D
FPGA
Microcontroller Overview
 Software
‘brains’ on a 68HC11
 Manages memory-mapped ‘smart’
peripherals (LCD, Keypad, Audio)
 Reads keypad state
 Creates images for menu user interface
on LCD.
 Controls robot path following, with
FPGA.
 Debugging information out RS-232.
FPGA
Kevin Chang
SRAM
Peripherals
Microcontroller
ROM
FPGA
Registers
Card
Reader
Interrupts
A/D
Motors
Valve
Solenoids
FPGA Overview
 XCS10
FPGA device
 Interface between microcontroller and
‘dumb’ peripheral devices.
 Chip selection based on address bus
 Registers for valve controls and motor
controls.
 Interrupt detector and interrupt
controller.
Chip Selection
 Reserve
a portion of the address space
to specify chip needed
 Use a multiplexer to determine the
appropriate chip from the address bus
 Enable the appropriate chip
Interrupt Controllers
 The
HC11 only has two interrupt inputs
 The FPGA must have an interrupt
controller because we had so many
devices
 It lets the microcontroller know that an
interrupt has occurred, and allows the
HC11 to determine the specific device
 Allows masking to disable certain
interrupts
Registers for Motor and Valve
Controls
 FPGA contains
registers to control the
motor controls and valve controls.
 Registers will contain information
pertaining to the device and duration.
 Valve controller - # of the valve.
 Motor controller – revolutions to
execute, direction, speed.
Peripherals
Andrew Jenkins
SRAM
LCD
Keypad
Path
Sensor
Microcontroller
ROM
Audio Out
FPGA
Registers
Card
Reader
Interrupts
A/D
Motors
Valve
Solenoids
Peripheral Devices Overview
 Motor
Controller for mobility.
 Valve Controllers for liquid dispensing.
 Graphic LCD Display for user’s menu.
 Keypad for user’s selection.
 Audio IC for voice prompts.
 Sensor for path finding.
 Magstripe readers for account balance,
identifying information, queueing.
Valves
 Considering:
Lawn
Sprinkler valves,
medical equipment
valves.
 Relay, SSR or
Power FET driven
 Flow control by
managing open time
in FPGA
Motor Driver
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Planned robotic base
includes motors and
matching H-Bridges.
 Probable upgrade to
stepper motors.
 Purchase ASAP, so
we can upgrade if
necessary (weight).
 Interface circuit to
match FPGA drive
characteristics,
prevent damage to
FPGA.
Power Supply
Julie Lam
SRAM
LCD
Keypad
Path
Sensor
Microcontroller
ROM
Audio Out
FPGA
Registers
Interrupts
A/D
Motors
Power
Supply
24V
110VAC
Card
Reader
12V
5V
5V Analog
Valve
Solenoids
Power Supply Overview
 From
~110VAC Wall outlet,
fused.
 Dual transformers (24VValve, LV Logic).
 Bridge rectifier, linear
regulators, filter capacitors.
 Decoupling capacitance.
 Must meet weight
requirements of motor &
base.
Timeline
Risks and Contingency
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Inadequate funding
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Inadequate time to implement
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Remove robotic motion, emphasize on user
interface.
Scale back – the design is modular.
Pre-determined path or simpler path following.
Eliminate problematic peripherals.
Errors on PCB
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Early PCB Rev. 1, portions can be wirewrapped.
Budget
Item
PCB, 4 layer FR4, 2ct. Min buy
Robotic base, w/motors
Upgraded motors/H-Bridges
Valves & Pumps
Plumbing & Mechanical Support
LCD
Keypad
Relays
Power Supply Components
Microcontroller + Memory Parts
FPGA Parts (excl. FPGA)
Interface Parts
Magstripe Readers
Price Ea. Qty Line Est.
110
3
330
139
1
139
75
2
150
14 16
224
120
1
120
60
2
120
25
1
25
7 16
112
50
3
150
40
3
120
40
3
120
60
3
180
60
3
180
1970
Conclusion
SRAM
LCD
Keypad
Path
Sensor
Microcontroller
ROM
Audio Out
FPGA
Registers
Interrupts
A/D
Motors
Power
Supply
24V
110VAC
Card
Reader
12V
5V
5V Analog
Valve
Solenoids