Stability Dynamics LG-Alert User manual

LG-AlertTM Ver 1.06 Lateral Acceleration Indicator Owner’s Manual
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Stability Dynamics Ltd. 04/04/06 “U.S. Patent 6,130,608” Page 1
INTRODUCTION
The LG-AlertTM Lateral Acceleration Indicator is intended for use as an early alert system to
assist drivers in recognizing when they are exceeding set maximum maneuvering limits of the
vehicle. This device monitors and displays lateral “g” forces perpendicular to the vehicle
direction of travel in real time. The lateral sensitivity of the device can be adjusted using the
digital push buttons on the front of the base unit. ‘00’ is least sensitive and ‘99’ is most
sensitive. An auxiliary horn jack provides an additional signal indicating the full scale of the
device has been exceeded. Signal output jacks provide voltages biased at +2.5 VDC
proportional to applied ‘g’s for data logging or trip recording applications. Internal filtering
reduces the effects of high frequency accelerations associated with bumps and vibration.
OPERATING PRINCIPLE
The heart of the LG-AlertTM Lateral Acceleration Indicator is a complete acceleration
measurement system contained in a hermetically sealed monolithic IC. The signal conditioning
circuitry incorporates a force-balance control loop and bias adjustment to center the signal about
zero. This provides a bi-polar voltage proportional to the applied “g” force. The absolute value
of the lateral signal is determined and outputted to the display module. Internal temperature
regulation of sensitive IC’s virtually eliminates error associated with changes in surrounding
temperature. The device can be set to display a full scale lateral acceleration range of between
0.17 and 1 “g” force.

LG-AlertTM Ver 1.06 Lateral Acceleration Indicator Owner’s Manual
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Stability Dynamics Ltd. 04/04/06 “U.S. Patent 6,130,608” Page 2
LATERAL FORCES ON VEHICLES
Turning a corner causes the vehicle to be
thrown outwards. When the force becomes
large enough the vehicle will either slide or
overturn. Lateral forces on the vehicle can
be determined by adding the radial
acceleration associated with turning corner
with the tilt component related to earth’s
gravity.
A tilt table can be used to establish a safe setting for the LG-AlertTM. The relationship between
digital setting and full-scale sensitivity are shown in the setup table. Alternatively the device can
be set by an experienced driver and tested under actual vehicle operating conditions to determine
a conservative setting for the device.
TURNING A CORNER
a = V2/R
a = acceleration (m/s2)
R = Radius (m)
V = Velocity (m/s)
F = Force (N)
m = mass (kg)
E.g., R=50m, V=40 km/h
a = V2/R
= (40*1000/3600) 2/50
=2.469m/s2
= (2.469 m/s2)/(9.81 m/s2)
= 0.25 “g’s”
=(0.25 of earth’s gravity)
FORCES ON AN INCLINED SURFACE
Acceleration = SIN(tilt angle) * earth’s gravity
Earth’s Gravity = 9.81 (m/s2)
The LG-AlertTM displays the total lateral acceleration
on the vehicle which is the sum of the turning acceleration and the component associated with
gravity (e.g., from an inclined surface).
Lateral Acceleration
Right Left
O
pp
Hyp Adj
v
R
a

LG-AlertTM Ver 1.06 Lateral Acceleration Indicator Owner’s Manual
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Stability Dynamics Ltd. 04/04/06 “U.S. Patent 6,130,608” Page 3
WHERE TO INSTALL
Both base and display modules should be located within the driver compartment. The display
module can be positioned anywhere that is convenient for viewing by the vehicle operator. The
display can be configured to mount to the dash or frame above the windshield. The SAE
suggests instruments should be located 0.71 m (28 in) from the driver’s eye, no more than 45
degrees below the horizon, within 30 degrees of straight ahead. The base module should be
positioned as low in the cab as possible using the two meter cable provided. It must be firmly
attached to the vehicle framework and as close to level as possible. Access to the base units
front and rear panels should not be obstructed to allow adjustments to be made. The front and
rear panels of the base unit must be aligned with the vehicles forward direction of travel. Cables
should be located away from contact by people and equipment and secured to reduce fatigue due
to vibration.
INSTALLATION
The LG-AlertTM requires only 2 cables to be connected to function. One cable provides 12 VDC
from the vehicle fuse panel. The second cable connects the display unit to the base module. A
fast blow fuse provides protection for the device. The power lights should illuminate upon
powering of the unit. There is a warm-up period of about 10-20 seconds where the device may
display an imbalance. During installation the device can be tested for functionality by attaching
cables and rotating the base module as shown.
Display Module Base Module
Side
Views
Fasteners to
vehicle
Front View
Power
LG-
A
lert
TM
Base Module Powe
r
Fasteners to vehicle

LG-AlertTM Ver 1.06 Lateral Acceleration Indicator Owner’s Manual
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Stability Dynamics Ltd. 04/04/06 “U.S. Patent 6,130,608” Page 4
Front View Base Unit
5 5
Sensitivity Adjustmen
t
+5VDC Suppl
y
+15 VDC Suppl
y
-15 VDC Suppl
y
Self Test Button
Cover Fasteners
Cover Plate
Bar Graph Mode (Bar or Dot)
Jumper on for Bar mode
Jumper off for Dot Mode
Audio Vent
Audio buzzer plug
Cable to Base Unit
Indicator LED’s
Power Indicato
r
LED Bar (100 % of Full Scale g’s)
LED Bar (90 % o Full Scale g’s)
LED Bar (80 % of Full Scale g’s)
LED (70 % of Full Scale g’s)
LED (60 % of Full Scale g’s)
LED (50 % of Full Scale g’s)
LED (40 % of Full Scale g’s)
LED (30 % of Full Scale g’s)
LED (20 % of Full Scale g
’s)
Rear View Base Unit
Fuse
12 VDC
From Battery
DB9 connector to Display
Lateral Signal Output Jack
Lateral Zero Adjust
Auxiliary Horn Jack
Axial Signal Output Jack
Vertical Signal Output Jack

LG-AlertTM Ver 1.06 Lateral Acceleration Indicator Owner’s Manual
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Stability Dynamics Ltd. 04/04/06 “U.S. Patent 6,130,608” Page 5
LOCATIONS TO AVOID
The display module can be placed in almost any location, convenient for viewing by the vehicle
operator. The device however should not be located where it may obstruct the vehicle operator’s
visibility.
The base module must be protected from transient conditions and impact.
 Do not locate the device in an area that may be exposed to the weather.
 Do not locate in areas of high humidity or temperature extremes (e.g., engine compartment)
 Do not locate in areas exposed to turbulent air from fans, doors or windows.
 Do not locate in areas exposed to high electromagnetic interference.
 Do not locate in areas of extreme mechanical vibration. (E.g., bolted to the engine)
 Do not locate in areas that may allow impact from people or equipment.
 Do not route cables through areas of high electrical magnetic interference.
TROUBLE SHOOTING
NO POWER
Check fuse and power connections.
Base and display units should have all power lights illuminated.
If any one of the four power supply lights is not illuminated the device may malfunction.
Green, yellow and red on the base module indicate status of the three power supplies
(+5,+15,-15 Volts). The red led on the Display indicates +12VDC to the display module.
FALSE ALARMS
• First check all cables and connections.
• Loose wires may cause the device to behave erratically.
• Check for damaged wire between base and display unit.
• Check the supply voltage to the device. Voltages less than 11 VDC or greater than 18
are outside the device specification range and may cause false readings. Abnormal
supply voltage fluctuations caused by faulty equipment or loose wires may cause the
highly sensitive amplifier circuits to give a false reading or appear unbalanced.
12VDC input Power

LG-AlertTM Ver 1.06 Lateral Acceleration Indicator Owner’s Manual
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Stability Dynamics Ltd. 04/04/06 “U.S. Patent 6,130,608” Page 6
UNBALANCED OPERATION
The device may have shifted during service or the characteristics of the vehicle may change
over time causing the device to be out of balance. This error can be removed by zeroing the
device. This is accomplished using the adjustment screw on the rear panel of the base unit.
If the left and right balance of the device cannot be corrected with the zero adjust the device
may require servicing.
ZEROING THE DEVICE
The device can be zeroed using a tiny 1/16” flat screw driver
to turn the zero adjust screw found on the rear panel of the
base module. Make sure the vehicle is on a level surface
before starting. Count the rotations of the zero adjustment
screw between one indicator light on the display for left and
right lateral accelerations. For example turn the zero
adjustment screw until only one green light is illuminated on the display module. Count the
number of turns required to pass through zero and illuminate one light the other way.
Simply divide the number of turns by two and rotate adjustment pot to the middle-point,
which should be close to zero. A setting of ‘99’ on the “sensitivity adjust” digital push
button will provide the maximum gain to easily visualize the error. Make sure the device is
re-set back to its original digital push button setting after zeroing.
BAR GRAPH MODE
The BAR GRAPH MODE is selected by the jumper found inside the
display module. The faceplate of the unit must be removed to expose the
circuit board. The bar graph mode jumper is found in the middle of the
circuit board. When the jumper is on the contact pins the display is in full
bar mode. When the jumper is removed the display changes to moving
dot mode.
DISABLING THE INTERNAL AUDIO ALARM
The display’s internal audio alarm can be disabled by removing the buzzer
plug. The faceplate of the unit must be removed to expose the circuit
board. The buzzer plug is found on the bottom left side of the circuit
board. When the plug is connected the internal buzzer is enabled. When
the plug is removed the buzzer is disabled. The auxiliary horn jack found
on the rear of the base unit is not disabled by this procedure. To disable
the auxiliary horn it must be unplugged from the base unit.
Lateral Zero
Adjust Screw
LG-Alert
Display
Unit
POWER

LG-AlertTM Ver 1.06 Lateral Acceleration Indicator Owner’s Manual
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Stability Dynamics Ltd. 04/04/06 “U.S. Patent 6,130,608” Page 7
SET-UP OF THE LG-AlertTM
The Lateral Acceleration Indicator is factory set at a digital setting of ‘55’ corresponding to first
alert occurring at a static tilt angle of approximately 15 degrees (0.26 ‘g’s). The device may be
adjusted by removing the base unit front panel and changing the digital setting. Static tilt table
specifications from the factory may be different than the “as equipped” configuration of the
vehicle. The dynamic response of the vehicle is highly unpredictable and can have a profound
effect on stability. Vehicle characteristics and response of the LG-AlertTM define the
recommended setting, as described in the NRC report to Transport Canada, “Development of a
Training Program for Drivers of High Capacity, High Center of Gravity Airport Rescue and Fire
Fighting (ARFF) Vehicles, Dec. 10, 1998”. Management may choose a sensitivity that is even
more conservative. Once a setting for a vehicle has been established, management must put in
place a clear policy that the device is never altered. Any change in device setting must be
clearly documented and all personnel informed, especially if the device is rendered less
sensitive. A routine inspection of the device setting and operation should be included in the
short test drive undertaken at the beginning of each shift. The self-test button can be pressed to
ensure the device is fully operational. The relationship between LG-AlertTM digital setting and
the associated ‘g’ forces to activate each of the three warning stages (lights 8,9 and 10) is shown
below.
LG-Alert Sensitivity Table
Digital LATERAL TILT ANGLE LATERAL ACCELERATION
Push Button light 8 light 9 light 10 light 8 light 9 light 10
Setting is on at is on at is on at
00 - 99 (deg) (deg) (deg) ('g's) ('g's) ('g's)
99 8.0 9.1 10.0 0.14 0.16 0.17
95 8.5 9.6 10.6 0.15 0.17 0.18
90 9.1 10.3 11.4 0.16 0.18 0.20
85 9.8 11.1 12.3 0.17 0.19 0.21
80 10.5 11.9 13.2 0.18 0.21 0.23
75 11.3 12.8 14.3 0.20 0.22 0.25
70 12.2 13.7 15.4 0.21 0.24 0.27
65 13.1 14.8 16.6 0.23 0.25 0.29
60 14.2 15.9 17.9 0.24 0.27 0.31
55 15.3 17.1 19.4 0.26 0.29 0.33
50 16.5 18.4 20.9 0.28 0.32 0.36
45 17.7 19.8 22.6 0.30 0.34 0.38
40 19.1 21.3 24.4 0.33 0.36 0.41
35 20.6 22.9 26.4 0.35 0.39 0.44
30 21.7 24.7 28.5 0.37 0.42 0.48
25 24.0 26.5 30.8 0.41 0.45 0.51
20 25.9 30.1 33.3 0.44 0.50 0.55
15 30.5 35.3 39.0 0.51 0.58 0.63
10 36.0 42.0 48.0 0.59 0.67 0.74

LG-AlertTM Ver 1.06 Lateral Acceleration Indicator Owner’s Manual
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Stability Dynamics Ltd. 04/04/06 “U.S. Patent 6,130,608” Page 8
LIMITATIONS OF THE LG-AlertTM
This device is intended as an early alert system to assist drivers in recognizing when
they are approaching maneuvering limits that are potentially unstable. While this device
can provide invaluable information to the operator of the vehicle, it must be recognized
that the LG-AlertTM has limitations.
There is an associated warm-up time as with many electronic devices in which accuracy
and balance of the device may be in error. Extremes in surrounding temperature (<< 20
C >>) will have an adverse effect on the zero bias signal level during the warm up
period. If possible the device should be powered at all times to reduce warm-up time.
Typical quiescent current is approximately 200 mA, 12VDC supply at 25 Celsius. At
colder operating temperatures the device will require more power to maintain the
temperature of the sensitive internal accelerometer IC’s.
 The device will not prevent the vehicle from overturning.
 The device cannot work without a suitable, steady power source (there are no
batteries).
 The device may not work properly if the power supply drops below 11 or rises above
18 VDC.
 The device can’t operate properly if it is not installed properly. The base module
must be level when the vehicle is loaded and on level ground. Any error in the
device orientation will appear as an error on the display module.
 The device will not work properly if the base module’s orientation is altered by impact
from people or equipment. Ensure that a routine is initiated that inspects functionality
of the device and orientation of the base module.
 The audio alarm cannot alert the vehicle operator if it is disabled.
 The device may function improperly if the cable between the base and display
modules is altered or lengthened. Consult manufacturer regarding cable length
limitations.
 The device may malfunction if the cable between the base and display modules is
routed through an area of high electromagnetic interference (e.g., through engine
compartment). A specially shielded cable may be required if electromagnetic
interference disrupts signal reliability.
 The device power supply must be between 11 and 18 VDC. Extraneous noise or
high voltages from the vehicle alternator circuit may cause internal damage to the
device. If this is a concern a power conditioning circuit should be installed between
the device and the vehicle battery circuit to filter out noise.
The LG-AlertTM is not a substitute for property, disability, life or any other insurance of
any kind. Appropriate insurance coverage is your responsibility. Consult your
insurance agent. The LG-AlertTM Lateral Acceleration Indicator is NOT to be relied on,
wholly, or in part, as a substitute for proper driver training, vehicle operation and
continued instruction respecting the safe operating parameters within which a vehicle
must be operated.

LG-AlertTM Ver 1.06 Lateral Acceleration Indicator Owner’s Manual
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Stability Dynamics Ltd. 04/04/06 “U.S. Patent 6,130,608” Page 9
LIMITED WARRANTY
Stability Dynamics Ltd. warrants that the LG-AlertTM Lateral Acceleration Indicator to be
free from defects in materials and workmanship under normal use and service for one
year from the date of purchase. This warranty is in lieu of any other warranty, either
expressed or implied. No manufacturer, agent, representative, dealer or employee of
the company has the authority to increase or alter obligations or limitations of this
warranty. This warranty is limited to the repair or replacement of the LG-AlertTM Lateral
Acceleration Indicator, at the Company’s option, in situations where this unit is found to
be defective in materials and/or workmanship in normal vehicle use. This warranty does
not cover damage resulting from negligent handling, painting, disassembly, misuse or
lack of reasonable care. In no case shall Stability Dynamics Ltd.’s liability under any
other remedy prescribed by law exceed purchase price of the Lateral Acceleration
Indicator. Your Lateral Acceleration Indicator is not a substitute for property, disability,
life or any other insurance of any kind. Appropriate insurance coverage is your
responsibility. Consult your insurance agent.
The duration of this warranty, including that of merchantability of fitness for any
particular purpose, shall be limited to the period of 1 year from date of purchase.
Stability Dynamics Ltd., the manufacturers and their respective officers, directors,
agents and employees, or any or all of them, shall have no liability for any personal
injury, property damage or any consequential or incidental damage for breach of this or
any other warranty, expressed or implied whatsoever, even if the loss or damage is
caused by the Company’s negligence or fault. Some jurisdictions do not allow exclusion
or limitation of incidental or consequential damages so the above limitation or exclusion
may not apply to you. This warranty gives you specific legal rights and you may also
have other rights which may vary from province to province.
For repair within the warranty period, return this product postage prepaid along with
proof of purchase date to Stability Dynamics Ltd.. Please enclose a note stating the
nature of the difficulty. In the event that you have any questions concerning the use,
care and/or service of this product, please write, fax or email:
Stability Dynamics Ltd.
10 Trent Drive,
Campbellford, Ontario (Canada)
KOL 1LO
Voice : [phone]
Fax : [phone]
Email : [email protected]