Revolutiontm AV+The Revolution AV+ (TNT4700) isa unique combination IMU and magnetic
compass with advanced vibration detection
and sensor fault detection. It features 11sensors aligned, calibrated, and compensatedover a temperature range of -50C to 110C.
There are two independent serial channels(RS232 or RS485) to transfer either compass
or IMU data in industry-standard formats: asimple-to-decipher ASCII string for compass
data (NMEA 0183*) or an efficient binary
packet format for IMU data.
The sensor suite consists of 3D rate gyros, a3D MEMS accelerometer, a 3D MEMS
magnetometer, and a dual axis electrolytic tilt(eTilt) sensor. Accelerometer sensors have aselectable range of 2, 4, 8, or 16G. Rategyros operate in the range of 250/sec.
Magnetometer and electrolytic sensors are thesame used in all Revolution products. Output
measurement data rates of up to 27.5 or 50Hz
– depending on operating mode – can beselected.
The AV+ operates in either Compass or IMU
mode. In compass mode, easy-to-tunecomplementary filters blend accelerometer,gyro, and magnetometer data to produce
accurate estimates of attitude in dynamic
ambient conditions. Trigonometric 3D gimbal
equations are incorporated in the firmware toproduce azimuth, pitch, and roll relative to theearth’s North-East-Down (NED) frame ofreference. An optional GPS (NMEA) RMC
sentence can be input to correct for continuous
circling and magnetic variation between trueand magnetic north. The electrolytic tilt sensor
can be configured to automatically correct bias
drift in the MEMS accelerometer. Diagnostic
measurements include magnetic dip angle andhorizontal field strength that can be verified
with online geomagnetic model data to ensurethat interfering magnetic sources are correctlycompensated.
_________________________________* National Marine Electronics Association

In IMU mode, the measurement and diagnostic
packet can either be requested or
automatically streamed. The packet contents
include:
••
•
•••
•
•
•

Accelerometer X, Y, Z in mg
RMS X, Y, Z vibration in mg
Gyro X, Y, and Z - 0.01/sec resolution
Magnetic field X, Y, Z - 0.1 mOe resolution
eTilt angles - 0.01 degree resolution
Ambient temperature - 0.1C
Input voltage in mV
16-bit sensor error flags
16-bit serial error indicators

Inertial sensor measurements are normalized
for ambient temperature variation andcalibrated to be coaxial at room temperature.
Magnetic field measurements arecompensated using hard and soft ironcoefficients. RMS vibration measurements areproduced by high-pass filtering raw
accelerometer data. Corner frequency andsample size can be configured through theserial interface.

For more information, pricing, and availability,
please call or e-mail sales@tntc.com.

True North Technologies LLC • 43 Broad St. Suite B308 • Hudson, MA 01749 USA
Ph: 978-897-5400 • Email: sales@tntc.com • Website: www.tntc.com© 2022 True North Technologies LLC

Advance Information Subject to Change

Revolution™ AV+ Electronic Compass

IMU Packet Description
Byte
Offset Name
023468101214161820222426283032
3436
38404244

HeaderLength
TypeCount
Data1
Data2
Data3
Data4
Data5
Data6
Data7
Data8
Data9
Data10
Data11
Data12
Data13
Data14
Data15
Data16
Data17
Data18
Data19Chksm

Description
Packet header
Packet length
Packet IDPacket counter
Accel X
Accel Y
Accel Z
Mag X
Mag Y
Mag Z
Gyro X
Gyro Y
Gyro Z
eTiltX
eTiltY
Vibration X
Vibration Y
Vibration Z
Ambient Temp
Input Volts
Startup Test Status
Operating Status
Serial Status
16-bit checksum

Value /Range

Units

0x5AA54600-65535±16,000

1 mG/count±32,000

0.1 mOe/count±30,000

1 count = 0.01 °/sec±4500

0.01 °/count±16,000

1 mG/count-500 to 1200
0 to 45000
0 to 65535
0 to 65535
0 to 65535

0.1 °C/countmilliVolts
flags
flags
flags & code

Software SupportThe advanced capabilities of the AV+ are supported by updated Revolution PC software thatsimplifies engineering verification and integration tasks. The software allows a user to• Monitor and change settings• Save and restore configuration data
• Perform magnetic calibration• Capture and record selected measurement data in CSV file format• Maintain communication transaction logs and a setting change log
For users who need to write communication software, the NMEA 0183 protocol is widely used in
GPS receivers and marine equipment and is easily adapted for sending commands to theRevolution. A technical guide with the protocol details is available.

True North Technologies LLC • 43 Broad St. Suite B308 • Hudson, MA 01749 USA
Ph: 978-897-5400 • Email: sales@tntc.com • Website: www.tntc.com© 2022 True North Technologies LLC

Advance Information Subject to Change

Revolution™ AV+ Electronic Compass

Diagnostics
The AV+ can be configured to run a comprehensive test routine either on power up (POST), or
when a software reset command is issued, or in both cases. It performs a few measurement cycles
with electrostatic activation of offsets for MEMS sensors, and tests voltage, temperature, andelectrolytic impedance values required for proper operation. Failure flags are cleared or set when
the diagnostic run completes and normal operation resumes. Additional start-up time is roughly halfa second.

Sensor Specifications
Device Specification
Manufacturer
Mfr Part NumberRange
Bias drift*
Scale factor drift
Noise Density
Axis misalignment*
Resolution
Bandwidth
Nonlinearity

eTilt

Accelerometer

Gyro

Magnetometer

Spectron
SP5000±40°

KionixKX132-1211±16g
0.25 mg/°C
0.03%/°C
130 μg√Hz1%
60 μg2900 Hz
0.5%

Analog Devices
ADXRS642±250°/sec<0.01°/sec/°C0.1%/°C
0.02°/sec√HzHoneywell
HMC 1001/1002±1.6 Oersted

0.1%/°C.02°
3%<0.1°/sec
2000 Hz.01% FS<29nV/√Hz±1% FS
250 μOe
5 MHz.05%*Bias drift and axis misalignment are compensated by calibration at True North. Sensors arealigned coaxial and orthogonal within 0.1° or better. Bias drift is compensated over the fulloperating temperature range of -50 to 110°C.

General Specifications
Heading Performance
Parameter

ValueConditions

Accuracy1

 0.5 rms
 4.0 rms
 0.3
36 msec 80 90 Pitch / 180 Roll
27.5 HzStatic, Tilt < 35 Dip < 60
Dynamic, rate < 150/sec
Static, no filter
Minimum, no filter

Repeatability
Response time
Dip Angle Range
Tilt Range
Output update rate

With accelerometers
Compass mode

1 May require calibration after installation to eliminate effect of local magnetic field

Pitch and Roll Performance
Accuracy
Repeatability
Range 0.25 0.1
 90 Pitch/ 180 Roll

Factory calibrated
TypicalElectrical
Supply Voltage (VDD)
Supply Current

5.5 – 45 Vdc unregulated
40 mA operating
10 mA idle

TypicalTypicalTrue North Technologies LLC • 43 Broad St. Suite B308 • Hudson, MA 01749 USA
Ph: 978-897-5400 • Email: sales@tntc.com • Website: www.tntc.com© 2022 True North Technologies LLC

Advance Information Subject to Change

Revolution™ AV+ Electronic Compass

General Specifications continued
Sensor Sampling Rates (IMU mode)
Parameter
Accelerometers
Gyros
Magnetometer
ElectrolyticValue
25,600 Hz
800 Hz800 Hz400 HzConditions
KX132 internal
Each component
Each component
Both pitch and roll

-50 to 110°C-55 to 150°C
0 to 90%
200g
5000g

Non-condensing
Max horizontal with electrostatic tilt sensor
Without eTilt sensor

Environmental
Operating Temp
Storage Temperature
Humidity
Shock

MechanicalEnclosure
PCB Size
PCB MountingConnectors
WeightHammond Mfg1591MFL (optional water-tight enclosure available)
1.8"W x 3.0"L x 0.6"H4 #4 screws, 1.4" x 2.6" spacing
8 pin, single-row, 0.1" friction header – RS-232 and RS-485
6 pin RJ12 modular jack or 9-pin D-Sub – RS-232
3 oz. in box

Interface
Signal type
Baud rate
Character Format
Input Buffer Size
Output Buffer Size
Output Format
Output Data Rate
Operating Modes

RS-232 and RS-485
4800, 9600, 19200, 38400, 57600, and 115,200 bps
8 data, no parity, 1 stop
100 characters
100 characters
NMEA 0183 and binary
Up to 27.5 Hz compass mode, 50Hz IMU mode
Compass Continuous or Sample, IMU Streaming or request

Angle Units

Degrees, mils, radians, 16-bit integer (1 LSB = 0.0055°)

True North Technologies LLC • 43 Broad St. Suite B308 • Hudson, MA 01749 USA
Ph: 978-897-5400 • Email: sales@tntc.com • Website: www.tntc.com© 2022 True North Technologies LLC

Advance Information Subject to Change

Revolution™ AV+ Electronic Compass