Download ppt - School of Electrical and Computer Engineering at Georgia Tech

Automotive Applications of Display Systems
and Human-Machine Interfaces using a
Dash-Mounted Touch Screen Computer
April 29, 2010
Assim Addous
Sam Coogan
Santiago Hässig
Martin Perry
Dash-Mounted Automotive HMI
EcoCAT Overview
• Automotive Human-Machine Interface (AHMI)
to display vehicle information to driver
• Modern vehicles contain wealth of disparate
data
• OEMs and car enthusiasts seek a
consolidating interface
• Must be below $1,200 to be competitively
priced as vehicle upgrade package
Design Objectives
Real-time
data
Proposed
Fuel efficiency
Actual
GPS
Motor and engine operating points Motor and engine operating points
Emissions composition
2-mode transmissions status
Diagnostic Historical
data
data
Battery SOC
Projected mileage on current drive
GPS tracing
cycle
Fuel saved
Speed history
Low fuel
Oil pressure and temperature
Engine overheating
Battery temperature
Vehicle Panel
Engine Panel
2-Mode Panel
Electric Panel
GPS Panel
Video Demonstration
Packaging
Hardware Overview
CAN Controller
reads in signals
from HUB
HMI Computer
parses USB data
Hardware Selection
Custom Built CAN Hub
•6 DB-9 ports
•Vehicle cockpit
•Cargo area
NI USB CAN Controller
•1 DB-9 Port
•Highspeed CAN
•500 kBaud
Lenovo Desktop
•Windows XP Home
Xenarc 705TS
•x86 Architecture
•7.5” display
•LabVIEW compatible
•4-wire, USB touch interface
•6 USB ports
•High viewing angle
•Antiglare
•800x480 resolution
CAN-bus Topology
Software Development
• LabVIEW Designed
– Uses Virtual Instruments (VI) library for CAN
messages
– Frame to channel conversion library
– Easy to add new signals
• Compiled to standalone executable
• Executable run as OS shell
Acceptance Testing
• Packaged within dash of vehicle
• Demoed in vehicle using previouslyobtained data
• Signals replayed by vehicle controller
– Data from vehicle run in December
– Transparent to AHMI
– Displayed data values compared to known
values to ensure accurate display
Power Handling
• Power on
– Power applied when ignition moves to accessory
– Computer BIOS adjusted to boot when power is applied
– Executable runs on OS startup
• Power off
– Soft power off switch on display
– Handled by driver before car shutdown
– Not ideal, but simple and intuitive
• Power integrity
– Will not experience power or voltage spikes
Computer Power
• Computer board uses 19V
• Voltage detection on computer prevents
lower voltage
• Uses DC-AC inverter and original AC-DC
adapter to power PC
Prototype Cost
Component
List Price
Actual Cost
Can Controller
$399
$300
HMI Computer
$199
$199
VGA Touchscreen
$279
$0
DC-AC Inverter
$30
$30
GT CAN Hubs
$30
$0
$5090
$0
$95
$0
$6122
$429
NI LabVIEW Professional
Windows XP License
Total
Prototype Labor
Labor Category
Time Spent
Cost
CAN Bus configuration
32
$3,840
LabVIEW development
50
$6,000
OS configuration
24
$2,880
Hardware integration
40
$4,800
Vehicle installation
25
$3,000
Total Labor Costs
171
$20,520
Hardware Cost
Total Costs
$6,122
$26,642
We assume an engineer making $40 per hour, with a 3x multiplier to cover
benefits, overhead, etc., resulting in $120 per hour.
Costs for 10,000 Units
Component
Cost per Unit
# of Units
Total Cost
Can Controller
$399
10,000
$3.9M
HMI Computer
$199
10,000
$1.9M
VGA Touchscreen
$279
10,000
$2.8M
DC-AC Inverter
$30
10,000
$0.3M
GT CAN Hubs
$30
10,000
$0.3M
$5090
1
$5090
$95
10,000
$1.0M
$8,580
1
$20,520
NI LabVIEW Professional
Windows XP License
Development Labor
Total
$10.2M
Per Unit Cost
$1,023
Future Work
• Power off initiated by vehicle power off
– Requires custom power circuitry
• Embedded operating system
– More lightweight for minimal hardware
– Quicker boot and shutdown
– Cheaper licensing and manufacturing for large scale
implementation
• Map database
• Direct DC power to computer
Temperature Control
• Vehicle interior can reach temperatures of up
to 120°F
• Have not observed any negative effects
• If implement large scale, hardware would
likely not cause issue
• As a prototype, difficult to mitigate
Technical Specifications
Component/Topic
Specification
Touch screen
Screen Size
7” – 8”
Touch control interface USB
Actual
Display interface
Power
HMI Computer
Maximum Size
VGA
12V
VGA
12V (native)
20cm x 12cm x
16.5cm
12V
Windows XP
Embedded
At least 3 USB 2.0
ports
Met
Power
Operating system
USB Interface
7.5”
USB
12V (through inverter)
Windows XP Home
4 USB 2.0 ports
Technical Specifications
Component/Topic
CAN Controller
Computer interface
CAN Technology
Specification
Actual
USB
2-wire, high-speed CAN
USB
High-speed or low-speed
CAN Interface
Software Interface
Software platform
CAN Interface
Wiring
DB-9
DB-9
LabVIEW 8.6
LabVIEW 8.6
No smaller than 20 AWG,
stranded wire
16 AWG, stranded wire
DB-9
One pair of twisted-pair
wiring for CAN high and low
signaling, one wire for
ground
DB-9
One pair of twisted-pair
wiring for CAN high and low
signaling, one wire for
ground
Connector
Wiring configuration