Specification

DMU30 Technical Datasheet
High Performance MEMS
Inertial Measurement Unit (HPIMU)
www.siliconsensing.com
Applications
y
Hydrographic surveying
Airborne survey and mapping
INS (Inertial Navigation Systems)
AHRS (Attitude and Heading Reference System)
GPS drop-out aiding
Maritime guidance and control
GNSS (Global Navigation Satellite System)
Autonomous vehicle control and ROVs
Machine control
MEMS alternative to FOG/RLG IMUs
ar
•
•
•
•
•
•
•
•
•
•
1 General Description
• Precision 6-DOF MEMS Inertial Measurement Unit
• Silicon Sensing’s latest VSG3QMAX inductive gyro
and capacitive accelerometer MEMS
• Excellent Bias Instability and Random Walk
Angular - 0.2°/hr, 0.02°/hr
Linear - 30μg, 0.05m/s/hr
• Non-ITAR
• Compact and lightweight - 68 x 61 x 62h (mm), 300g
• Internal power conditioning to accept 4.75V to 36V
input voltage
• RS422 interfaces
• -40°C to +85°C operating temperature range
• Sealed aluminium housing
• RoHS compliant
• In-house manufacture from MEMS fabrication to IMU
calibration
• Evaluation kit and integration resources available
• First class customer technical support
• Future developments and expansion capability
Multi sensor MEMS blending
Low power ‘sleep’ mode
Over-range output (reduced specification)
Additional sensor integration - GPS/
Magnetometer/Barometer
North finding mode
AHRS functionality
Other interface protocols and specifications
Custom and host application integration
DMU30 is a full six-degree-of-freedom inertial
measurement unit providing precise 3-axis outputs of
angular rate and acceleration, delta angle and velocity,
and temperature, at 200Hz.
Pr
el
im
in
Features
DMU30 is the first of a new family of High Performance
MEMS IMUs (HPIMU) incorporating precision VSG3QMAX
high-Q inductive resonating ring gyroscopes and
capacitive accelerometers.
DMU30 represents a realistic, alternative to established
FOG/RLG based IMUs due to its exceptional bias
stability and low noise characteristics, yet it is
comparatively compact, lightweight and offers low cost
of ownership.
Designed specifically to meet the growing demand
from high-end commercial and industrial market
applications for a ‘tactical’ grade non-ITAR IMU,
DMU30 utilises Silicon Sensing’s class leading
MEMS inertial sensors integrated and calibrated
using an in-house state-of-the-art test facility.
HPIMU development takes advantage of Silicon
Sensing’s wide-ranging multi sensor technologies
in a unique architecture to achieve a highly versatile
IMU design. Planned capabilities include common
mode error reduction, dynamic over-range output,
low-power ‘sleep’ mode and performance enhanced
sensor blending. Future developments will feature
GPS, magnetic and ambient pressure sensing, north
finding and AHRS functions.
© Copyright 2015 Silicon Sensing Systems Limited. All rights reserved. Silicon Sensing is an Atlantic Inertial Systems, Sumitomo Precision Products joint venture company.
Specification subject to change without notice.
DMU30-00-0100-132 Rev 1
Page 1
DMU30 Technical Datasheet
High Performance MEMS
Inertial Measurement Unit (HPIMU)
www.siliconsensing.com
4.75 to 36V 14
Regulators
Power Return 15
MPU
MOSI
MISO
Vref
SS
High
Performance
Gyro X
Accelerometer
(+X, +Z)
High
Performance
Gyro Y
Accelerometer
(-X, -Y)
High
Performance
Gyro Z
Temperature
Sensors
C.G. 18733
im
in
Run Mode
Sync
Prog
Reset
Chassis GND
SCLK
Accelerometer
(+Y, -Z)
y
Expansion
Feature
4
3
2
1
13
12
11
10
9
Analogue to
Digital
Converters
RS422
Driver
ar
8
7
6
5
Tx_Hi
Tx_Lo
Rx_Lo
Rx_Hi
62
Pr
el
Figure 1.1 DMU30 Functional Block Diagram
61
68
All dimensions in millimetres.
Figure 1.2 DMU30 Unit Overall Dimensions
© Copyright 2015 Silicon Sensing Systems Limited. All rights reserved. Silicon Sensing is an Atlantic Inertial Systems, Sumitomo Precision Products joint venture company.
Specification subject to change without notice.
Page 2
DMU30-00-0100-132 Rev 1
DMU30 Technical Datasheet
High Performance MEMS
Inertial Measurement Unit (HPIMU)
www.siliconsensing.com
2 Ordering Information
Item
Overall
Dimensions
Description
Part Number
mm
68 x 61 x 62H
DMU30-01-0100
y
High Performance
MEMS Inertial Measurement
Unit.
in
Customer Evaluation Kit (EVK)
comprising a
DMU30-01-0100, RS422 to USB
Connector, USB Driver and Data
Logging Software, Cables and
Connectors, Instruction Manual.
ar
DMU30 IMU
DMU30-01-0500
Length 600mm
DMU30-01-TBD
im
el
DMU30 Evaluation Kit
Not Applicable
Pr
Mating connector
plug and cable for DMU30
DMU30 Mating Connector
© Copyright 2015 Silicon Sensing Systems Limited. All rights reserved. Silicon Sensing is an Atlantic Inertial Systems, Sumitomo Precision Products joint venture company.
Specification subject to change without notice.
DMU30-00-0100-132 Rev 1
Page 3
DMU30 Technical Datasheet
High Performance MEMS
Inertial Measurement Unit (HPIMU)
www.siliconsensing.com
Minimum
Typical
Maximum
Notes
Dynamic Range (°/s)
-200
–
+200
Clamped at ±205°/s
during over-range
Scale Factor Error (ppm)
-500
±100
+500
Factory fresh test
Scale Factor Non-Linearity
Error (ppm)
-500
±100
+500
Factory fresh test
-20
±15
Over operating
temperature range
factory fresh test
Bias Instability (°/h)
–
< 0.2
ar
3 Specification
Parameter
Random Walk ( °/h)
–
Bias Repeatability (°/h)
–
Gyro Bandwidth (Hz)
Noise (°/s rms)
VRE (°/s/g2 rms)
in
+20
im
0.4
0.04
As measured using the
Allan Variance method.
20
100
Bias Repeatability =
√(Biaswarmup)2 + (Biastoto)2 + (Biasageing)2 + (Biastemperature)2
±0.35
+0.7
Over operating
temperature range
10
85
90
-3dB point
User programmable
–
0.15
0.25
Wide band noise at
100Hz bandwidth
-0.006
±0.002
+0.006
10g rms stimulus
20Hz to 2,000Hz
-0.7
Pr
Gyro Cross Coupling (%)
< 0.02
el
Bias (°/hr)
y
Angular (Roll, Pitch, Yaw)
© Copyright 2015 Silicon Sensing Systems Limited. All rights reserved. Silicon Sensing is an Atlantic Inertial Systems, Sumitomo Precision Products joint venture company.
Specification subject to change without notice.
Page 4
DMU30-00-0100-132 Rev 1
DMU30 Technical Datasheet
High Performance MEMS
Inertial Measurement Unit (HPIMU)
www.siliconsensing.com
3 Specification Continued
Parameter
Minimum
Typical
Maximum
Notes
-10
–
+10
Clamped at ±10.01g
during over-range
Scale Factor Error (ppm)
-500
±100
+500
–
Scale Factor Non-Linearity
Error (ppm)
-500
±100
+500
Maximum error from best straight
line over ±10g
Bias (mg)
-5.00
±1.50
–
–
Bias Repeatability (mg)
–
ar
Over operating
temperature range
0.05
As measured using the
Allan Variance method.
0.05
0.06
3.5
7
Bias Repeatability =
√(Biaswarmup)2 + (Biastoto)2 + (Biasageing)2 + (Biastemperature)2
±0.35
+0.70
Over operating
temperature range
10
85
150
-3dB point
User programmable
Noise (mg rms)
–
1.00
2.30
Wide band noise at
100Hz bandwidth
VRE (mg/g2 rms)
-0.15
±0.10
+0.15
3g rms stimulus
20Hz to 2,000Hz
-45
–
100
Note that this
exceeds operational
temperature range
–
±3
–
In the operational
temperature range
Acc Bandwidth (Hz)
-0.70
Pr
Acc Cross Coupling (%)
el
Random Walk (m/s/h)
0.03
im
Bias Instability (mg)
+5.00
in
Dynamic Range (g)
y
Linear (X, Y, Z)
Temperature Output
Range (°C)
Accuracy (°C)
© Copyright 2015 Silicon Sensing Systems Limited. All rights reserved. Silicon Sensing is an Atlantic Inertial Systems, Sumitomo Precision Products joint venture company.
Specification subject to change without notice.
DMU30-00-0100-132 Rev 1
Page 5
DMU30 Technical Datasheet
High Performance MEMS
Inertial Measurement Unit (HPIMU)
www.siliconsensing.com
4 Environment, Power and Physical
4.1 Normal Operation
Parameter
Minimum
Typical
Maximum
Notes
Operating Temperature
Range (°C)
-40
–
+85
Full specification
Storage Temperature
Range (°C)
-55
–
+100
–
Operational Shock (g)
–
–
95
6ms, half sinewave
Operational Shock (g)
(powered survival)
–
–
1,000
1.0ms, half sinewave
Operational Random
Vibration (g rms)
–
–
Non-Operational Random
Vibration (g rms)
–
–
Humidity (% rh)
–
Immersion Depth (m)
–
ar
y
Environment
20Hz to 2KHz
10
20Hz to 2KHz
–
85
Non-condensing
–
1
IMU is sealed
RS-422
–
Full duplex communication
–
200 (default)
–
User programmable
* future feature
–
460,800 (default)
–
User programmable
* future feature
–
< 1.0
1.2
Time to operational output
–
<5
20
Time to full performance
(mounting dependent)
–
<3
4
With 120  RS422
termination resistor
+4.75
+8
+36
Unit is calibrated at 8 volts
Size (mm)
–
68 x 61 x 62H
–
–
Mass (grams)
–
300g
–
TBC
Baud Rate (BPS)
Startup Time (s)
(operational output)
Startup Time (s)
(full performance)
Power (watts)
Supply Voltage (V)
el
Data Rate (Hz)
–
Pr
Communication Protocol
(standard)
im
Electrical and Interface
in
3.0
Physical
Notes:
DMU30 is designed for 1m immersion in water (IP67).
To maintain integrity around the connector, it is essential
that the mating connector is a sealed type, or a suitable
sealing compound should be applied around the connectors.
© Copyright 2015 Silicon Sensing Systems Limited. All rights reserved. Silicon Sensing is an Atlantic Inertial Systems, Sumitomo Precision Products joint venture company.
Specification subject to change without notice.
Page 6
DMU30-00-0100-132 Rev 1
DMU30 Technical Datasheet
High Performance MEMS
Inertial Measurement Unit (HPIMU)
www.siliconsensing.com
4.2 Absolute Minimum/Maximum Ratings
Minimum
Maximum
-0.3V
+37V
–
2kV HBM
–
6,500g 0.1ms 1/2 sine
Electrical:
Vdd
ESD protection
Environmental:
Shock (non-operational)
15 years
12,000 hours
–
im
Notes:
Improper handling, such as dropping onto hard
surfaces, can generate every high shock levels
in excess of 10,000g. The resultant stresses can
cause permanent damage to the sensor.
–
in
Powered
ar
Unpowered
y
Life:
Pr
el
Exposure to the Absolute Maximum Ratings for
extended periods may affect performance and
reliability.
© Copyright 2015 Silicon Sensing Systems Limited. All rights reserved. Silicon Sensing is an Atlantic Inertial Systems, Sumitomo Precision Products joint venture company.
Specification subject to change without notice.
DMU30-00-0100-132 Rev 1
Page 7
DMU30 Technical Datasheet
High Performance MEMS
Inertial Measurement Unit (HPIMU)
www.siliconsensing.com
5 Typical Performance Characteristics
This section shows the typical performance of DMU30.
5.1 Performance Characteristics
Pr
el
im
in
ar
y
This section will include comprehensive test result
statistics of all main IMU performance parameters.
© Copyright 2015 Silicon Sensing Systems Limited. All rights reserved. Silicon Sensing is an Atlantic Inertial Systems, Sumitomo Precision Products joint venture company.
Specification subject to change without notice.
Page 8
DMU30-00-0100-132 Rev 1
DMU30 Technical Datasheet
High Performance MEMS
Inertial Measurement Unit (HPIMU)
www.siliconsensing.com
6 Glossary of Terms
7 Interface
ADC
Analogue to Digital Converter
ARW
Angle Random Walk
AWG
American Wire Gauge
BPS
Bits Per Second (or Baud Rate)
BW
Bandwidth
C
Celsius or Centigrade
DAC
Digital to Analogue Converter
DPH
Degrees Per Hour
DPS
Degrees Per Second
DRIE
Deep Reactive Ion Etch
EMC
Electro-Magnetic Compatibility
ESD
Electro-Static Damage
F
Farads
h
Hour
HBM
Human Body Model
HPIMU
High Performance MEMS Inertial
Measurement Unit
Physical and electrical inter-connect and RS422
message information
7.1 Electrical Interface
4.75 to 36V
Kilo
MDS
Material Datasheet
Micro-Electro Mechanical Systems
mV
Milli-Volts
NEC
Not Electrically Connected
NL
Scale Factor Non-Linearity
Pr
MEMS
OEM
Original Equipment Manufacturer
OT
Over Temperature
PD
Primary Drive
PP
Primary Pick-Off
RC
Resistor and Capacitor filter
RT
Room Temperature
s
Seconds
SF
Scale Factor
SMT
Surface Mount Technology
SOG
Silicon On Glass
SD
Secondary Drive
SP
Secondary Pick-Off
TBA
To Be Advised
TBC
To Be Confirmed
TBD
To Be Determined
V
Volts
y
Tx_Lo
Tx_Hi
in
ar
SYSTEM
HOST
im
Hertz, Cycles Per Second
K
Rx_Hi*
el
Hz
14
Rx_Lo*
RESET*
RUN MODE*
SYNC*
0V
6
5
7
DMU30
8
10
13
12
15
* These connections are optional
and can be left not connected.
C.G. 18734
Figure 7.1 Required Connections for RS422
Communications with DMU30
7.2 Physical Interface
15
8
9
1
15 Way Micro-Miniature Connector Type DCCM-15S
C.G. 18735
Figure 7.2 DMU30 Socket Connector
© Copyright 2015 Silicon Sensing Systems Limited. All rights reserved. Silicon Sensing is an Atlantic Inertial Systems, Sumitomo Precision Products joint venture company.
Specification subject to change without notice.
DMU30-00-0100-132 Rev 1
Page 9
DMU30 Technical Datasheet
High Performance MEMS
Inertial Measurement Unit (HPIMU)
www.siliconsensing.com
7.3 Connector Specification
7.5 Communications with DMU30
DMU30 uses a 15 way socket connector which is
the micro-miniature ‘D’ type range of connectors,
produced by Cinch, Glenair and others.
The Run Mode pin on the connector is used to control
the output from the DMU30. The “Free Run” or “Enabled”
mode is active when the Pin is floating (not connected),
and the output will be enabled.
The DMU30 plug mating connector is a 15 way plug,
for example DCCM-15P (DCCM-15P6E518).
y
Silicon Sensing can supply a mating plug and cable to
interface to DMU30 (Part Number DMU30-01-TBD).
ar
7.6 Operational Message Output
In/Out
1,
2,
3,
4
Future
A SPI® comm port for future
expansion
I/O
5
Rx_Hi
The positive receive connection
required for the RS422
communication
I
6
Rx_Lo
The negative receive connection
required for the RS422
communication
I
7
Tx_Lo
The negative transmit connection
required for the RS422
communication
O
8
TX_Hi
The positive transmit connection
required for the RS422
Communication
O
9
Chassis
GND
Chassis ground
I
10
Reset
Microprocessor reset. Pin is
pulled low to reset the device.
Suggested implementation using
TTL logic
I
11
Factory Use
Used by SSSL for programming
purposes and should not be
interfaced with
N/A
Sync
Output signal that can be used by
an external system to synchronise
with DMU30
O
13
Run Mode
Device Enable/Disable. Pin is
pulled high or not connected
to enable the device. Pin is
pulled low to disable the device.
Suggested implementation using
TTL logic
I
14
+Volts
Input voltage to the DMU30. Can
be between 4.75V and 36V
I
15
GND
Ground connected to the DMU30
I
12
el
Table 7.1 Pin Information
The Output Message is output on a RS422 Serial output
at 460,800 baud using a non-return to zero protocol.
Each byte contains a start bit (logic 0), 8 data bits and
2 stop bits (logic 1). Data is output in big endian format
by default.
in
Signal
im
Label
Pr
7.4 Pin Information
Pin
The DMU30 output is disabled when the “Run Mode”
Pin is pulled low.
Data is output at a rate of 200 messages per second.
Each message contains 33 words (66 bytes) as described
in Table 7.2. The message is transmitted if the “Run
Mode” Pin is floating/HIGH.
If the “Run Mode” Pin changes to a LOW (Disable
output), while the message is being transmitted, the
message is completed before the output is disabled.
7.7 Sensor Sampling and Synchronisation
The inertial sensors within DMU30 are all sampled at
1,000Hz. The ‘Sync Pulse’ on the connector is set
HIGH at the start of the sampling and returned to LOW
when the last inertial sensor is sampled. Pulses are
therefore seen on the connector at 1,000Hz.
The inertial sensor measurements are then filtered with
a 2nd order low pass filter, also running at 1000Hz.
The factory default setting for this filter has a corner
frequency of > 85Hz.
The internal sequence for DMU30 is:
• Cycle 1: Sample Sensors, 2nd order Filter
• Cycle 2: Sample Sensors, 2nd order Filter, Calculate
Sensor Compensation
• Cycle 3: Sample Sensors, 2nd order Filter, Apply
Sensor Compensation
• Cycle 4: Sample Sensors, 2nd order Filter, Calculate
Delta Theta and Vels
• Cycle 5: Sample Sensors, 2nd order Filter, Transmit
Message
The message is transmitted after the ‘Sync Pulse’
associated with Cycle 5 has returned LOW. The inertial
data included in the message is generated when the
‘Sync Pulse’ associated with Cycle 3 is HIGH. This
enables the external equipment to synchronise with the
time when the inertial data is valid.
© Copyright 2015 Silicon Sensing Systems Limited. All rights reserved. Silicon Sensing is an Atlantic Inertial Systems, Sumitomo Precision Products joint venture company.
Specification subject to change without notice.
Page 10
DMU30-00-0100-132 Rev 1
DMU30 Technical Datasheet
High Performance MEMS
Inertial Measurement Unit (HPIMU)
www.siliconsensing.com
7.8 Operational Message Definitions
7.9 System BIT Flags
The data output message has the content and
sequence as shown in the table below:
7.9.1 System Startup BIT Flags
0
0
Header
16 Bit, 0x55AA
1
1
Message Count
16 Bit, 0 to 65535
decimal
2
2-3
Axis X Rate
32 Bit Single Precision
FP, (˚/s)
3
4-5
Axis X
Acceleration
32 Bit Single Precision
FP, (g)
4
6-7
Axis Y Rate
32 Bit Single Precision
FP, (˚/s)
5
8-9
Axis Y
Acceleration
32 Bit Single Precision
FP, (g)
6
10-11
Axis Z Rate
32 Bit Single Precision
FP, (˚/s)
7
12-13
Axis Z
Acceleration
32 Bit Single Precision
FP, (g)
8
14-15
Aux Input Voltage
9
16-17
Average IMU
Temperature
10
18-19
Axis X Delta
Theta
32 Bit Single Precision
FP, (˚)
11
20-21
Axis X Delta
Vel
32 Bit Single Precision
FP, (m/s)
12
22-23
Axis Y Delta
Theta
32 Bit Single Precision
FP, (˚)
13
24-25
Axis Y Delta
Vel
32 Bit Single Precision
FP, (m/s)
14
26-27
Axis Z Delta
Theta
32 Bit Single Precision
FP, (˚)
15
28-29
Aux Z Delta
Vel
32 Bit Single Precision
FP, (m/s)
16
30
System Startup
BIT Flags
16 Bit decimal value
17
31
System Operation
BIT Flags
16 Bit decimal value
18
32
Error Operation
BIT Flags
16 Bit decimal value
19
33
Checksum
16 Bit 2’s Complement
of the 16 Bit Sum of the
Previous 0-18 data items
TBA
y
Value / Unit
ar
Data Item
in
Word
el
im
Item
32 Bit Single Precision
FP, (volts)
Pr
32 Bit Single Precision
FP, (˚C)
Table 7.2 Operational Message Data
Output Definitions
© Copyright 2015 Silicon Sensing Systems Limited. All rights reserved. Silicon Sensing is an Atlantic Inertial Systems, Sumitomo Precision Products joint venture company.
Specification subject to change without notice.
DMU30-00-0100-132 Rev 1
Page 11
DMU30 Technical Datasheet
www.siliconsensing.com
7.9.2 System Operation BIT Flags
7.9.3 System Error Indication BIT Flags
TBA
TBA
Pr
el
im
in
ar
y
High Performance MEMS
Inertial Measurement Unit (HPIMU)
© Copyright 2015 Silicon Sensing Systems Limited. All rights reserved. Silicon Sensing is an Atlantic Inertial Systems, Sumitomo Precision Products joint venture company.
Specification subject to change without notice.
Page 12
DMU30-00-0100-132 Rev 1
DMU30 Technical Datasheet
High Performance MEMS
Inertial Measurement Unit (HPIMU)
www.siliconsensing.com
8 Design Tools and Resources Available
Part Number
Order/Download
DMU30 Brochure: A one page sales brochure describing
the key features of the DMU30 Inertial Measurement Unit.
DMU30-00-0100-131
Download
(www.siliconsensing.com)
DMU30 Datasheet: Full technical information on all
DMU30 Dynamic Measurement Unit part number options.
Specification and other essential information for assembling
and interfacing to DMU30 Inertial Measurement Unit, and
getting the most out of it.
DMU30-00-0100-132
Download
(www.siliconsensing.com)
DMU30 Evaluation Kit: DMU30 delivered with an RS422
to USB interface, plug-and-play real time display and logging
software and two interface cabling solutions DMU30-01-0100
unit included.
DMU30-01-0500
DMU30 Presentation: A useful presentation describing the
features, construction, principles of operation and applications
for the DMU30 Inertial Measurement Unit.
—
Download
(www.siliconsensing.com)
DMU30-01-0100-408
Download
(www.siliconsensing.com)
DMU30-01-TBD
Order
(www.siliconsensing.com)
([email protected])
DMU30-01-0100-TBD
Download
(www.siliconsensing.com)
—
Download
(www.siliconsensing.com)
y
Description of Resource
im
in
ar
Item
el
Solid Model CAD files for DMU30 Inertial
Measurement Unit:
Available in .STP and .IGS file formats.
68
26.5
33
76º
Pr
DMU30 Plug and Cable: A mating plug and
600mm long cable.
DMU30 Installation Drawing: CAD file containing host
interface geometry. Available in .STP and .IGS file formats.
Order
(www.siliconsensing.com)
([email protected])
70 PCD
52.1
0.5
RoHS compliance statement for DMU30 : DMU30 is fully
compliant with RoHS. For details of the materials used in the
manufacture please refer to the MDS Report.
© Copyright 2015 Silicon Sensing Systems Limited. All rights reserved. Silicon Sensing is an Atlantic Inertial Systems, Sumitomo Precision Products joint venture company.
Specification subject to change without notice.
DMU30-00-0100-132 Rev 1
Page 13
DMU30 Technical Datasheet
High Performance MEMS
Inertial Measurement Unit (HPIMU)
www.siliconsensing.com
8.1 DMU30 Evaluation Kit
9 Part Markings
The DMU30 Evaluation Kit enables the output data
from the DMU30 to be viewed and logged for testing
and evaluation purposes.
DMU30 is supplied with an adhesive label attached.
The label displays readable DMU30 part and part
identification numbers.
The part identification number is a numeric code;
WWYYXXXX R where:
WW = Manufacturing week number
YY
= Manufacturing year number
XXXX = Serial number
= Revision
y
R
im
Figure 8.1 DMU30 Evaluation Kit
in
ar
A 4x4 data matrix barcode containing the part
identification number is also displayed on the label.
DMU30
PT NO. DMU30-00-0100
SER NO. WWYYXXXX R
8.1.1 DMU30 Evaluation Kit Contents
DMU30 IMU (part number DMU30-01-0100).
Pr
• MEV RS485i to USB converter.
• CD containing the MEV drivers.
• USB memory stick containing the data logging
software.
• Mating plug and cable.
• User manual.
8.1.2 System Requirements
The DMU30 Evaluation Kit requires a PC with a USB port.
The requirements for the PC are as follows:
• Microsoft® Windows® XP (SP3 or greater), Vista®,
Windows 7 or Windows 8 Operating Systems.
The software has not been tested on any
other Operating System and therefore correct
functionality cannot be guaranteed.
MADE IN PLYMOUTH UK
DMU30
el
The DMU30 Evaluation Kit (part number DMU30-01-0500)
contains the following:
Figure 9.1 DMU30 Label
• Minimum of 500Mb of RAM.
• 500Mb of free hard drive space plus space for
logged data (typical data rate ≈ 50kbit/s).
• High power or self-powered USB 2.0 Port.
© Copyright 2015 Silicon Sensing Systems Limited. All rights reserved. Silicon Sensing is an Atlantic Inertial Systems, Sumitomo Precision Products joint venture company.
Specification subject to change without notice.
Page 14
DMU30-00-0100-132 Rev 1
DMU30 Technical Datasheet
High Performance MEMS
Inertial Measurement Unit (HPIMU)
www.siliconsensing.com
Figures 10.1 show the installation drawing for the
DMU30.
The DMU30 is designed for 4 point mounting using
M5.0 screws. During calibration alignment is achieved
using two external reference dowel holes on the base
of the DMU30. The dowel holes are designed to be
used with two Ø3mm (in accordance with
BS EN ISO 8734 or BS EN ISO 2338) dowel pins
provided by the host.
The DMU30 mounting screw torque settings will be
dependent on the host application; it will for example
vary depending on the specification of the screw, the
material of the host structure and whether a locking
compound is used. When securing a DMU30 to the
host system using steel M5.0 screws and a thread
locking compound the suggested torque setting is
0.2Nm for securing to an aluminium host structure.
This information is provided for guidance purposes
only, the actual torque settings are the responsibility
of the host system designer.
y
10 Installation Details
5.65
5.45
Ø 0.2
68
68
im
26.5
33
61
76º
in
ar
4x Ø
3.201
3.186
3.5 DP MIN
Ø 0.2
SLOT Ø
All dimensions in millimetres.
el
62
3.201
Ø
3.186
3.5 DP MIN
Ø 0.2
70 PCD
52.1
0.5
Pr
Figure 10.1 DMU30 Installation Drawing
+ Roll (R)
+X
+ Pitch (P)
+Y
+ Yaw (Y)
+Z
Figure 10.2 Axis Definitions
© Copyright 2015 Silicon Sensing Systems Limited. All rights reserved. Silicon Sensing is an Atlantic Inertial Systems, Sumitomo Precision Products joint venture company.
Specification subject to change without notice.
DMU30-00-0100-132 Rev 1
Page 15
DMU30 Technical Datasheet
High Performance MEMS
Inertial Measurement Unit (HPIMU)
www.siliconsensing.com
11 Packaging
12 DMU30 Construction and Theory of
Operation
Full packaging specification including package labelling
(TBD).
12.1 IMU Construction
DMU30 is an aluminium alloy assembly comprising
base, housing, sensor block, sensor assemblies and
IMU electronics.
ar
y
The base and housing are sealed using a self-forming
gasket and secured by four machine screws to
provide a waterproof enclosure. A micro-miniature
‘D’ type socket connector located on the top face of
the housing provides the electrical interface to the
host system. The top face of the housing displays the
DMU30 part marking information.
Pr
el
im
in
DMU30 is aligned to the host system using two
Ø3mm dowels in the host platform which locate with
matching dowel holes in the bottom face of the base.
The IMU is secured to the host using M5.0 machine
screws.
A precision machined aluminium 3-Axis Sensor
Block, secured to the DMU30 Base by machine
screws provides accurate alignment and support for
the DMU30 MEMS inertial sensor assemblies and
IMU electronics. Internally generated heat from the
sensor assemblies and IMU electronics is absorbed
into the sensor block and surrounding housing and
conducted to the host via the base and to the ambient
atmosphere via convection cooling fins in the housing.
The IMU electronics is a triple-stack PCB assembly
which is affixed to the sensor block by six spacers
and machine screws to provide stable and precise
alignment between the sensor assemblies.
12.2 Sensor Construction and Theory of
Operation
Silicon MEMS Inductive Ring Gyroscope
The silicon MEMS ring is 6mm diameter by 100μm
thick, fabricated by Silicon Sensing Systems using a
DRIE (Deep Reactive Ion Etch) bulk silicon process.
The ring is supported in free-space by sixteen pairs
of symmetrical legs which isolate the ring from the
supporting structure on the outside of the ring.
© Copyright 2015 Silicon Sensing Systems Limited. All rights reserved. Silicon Sensing is an Atlantic Inertial Systems, Sumitomo Precision Products joint venture company.
Specification subject to change without notice.
Page 16
DMU30-00-0100-132 Rev 1
DMU30 Technical Datasheet
High Performance MEMS
Inertial Measurement Unit (HPIMU)
www.siliconsensing.com
The tracks along the top of the ring form two pairs
of drive tracks and two pairs of pick-off tracks. Each
section has two loops to improve drive and pick-off
quality.
C.G. 18619
Figure 12.1 Silicon MEMS Ring
ν
el
im
in
The bulk silicon etch process and unique patented ring
design enable close tolerance geometrical properties
for precise balance and thermal stability and, unlike
other MEMS gyros, there are no small gaps to create
problems of interference and stiction. These features
contribute significantly to DMU30’s bias and scale factor
stability over temperature, and vibration immunity.
Another advantage of the design is its inherent
immunity to acceleration induced rate error, or
‘g-sensitivity’.
ar
y
One pair of diametrically opposed tracking sections,
known as the Primary Drive PD section, is used to
excite the cos2 mode of vibration on the ring. This
is achieved by passing current through the tracking
and, because the tracks are within a magnetic
field, causes motion on the ring. Another pair of
diametrically opposed tracking sections are known
as the Primary Pick-off PP section are used to
measure the amplitude and phase of the vibration
on the ring. The Primary Pick-off sections are in the
segments 90° to those of the Primary Drive sections.
The drive amplitude and frequency is controlled by a
precision closed loop electronic architecture with the
frequency controlled by a Phase Locked Loop (PLL),
operating with a Voltage Controlled Oscillator (VCO),
and amplitude controlled with an Automatic Gain
Control (AGC) system. The primary loop therefore
establishes the vibration on the ring and the closed
loop electronics is used to track frequency changes
and maintain the optimal amplitude of vibration over
temperature and life. The loop is designed to operate
at about 14kHz.
Upper Pole
Silicon
Pedestal Glass
Pr
Can Lid
Can Base
Magnet
Support Glass
ν
ν
Lower Pole
C.G. 18620
Figure 12.2 MEMS VSG3Q
Cos2θ
Vibration
Mode at
14kHz
MAX
Sensor
The ring is essentially divided into 8 sections with
two conductive tracks in each section. These tracks
enter and exit the ring on the supporting legs. The
silicon ring is bonded to a glass pedestal which in
turn is bonded to a glass support base. A magnet,
with upper and lower poles, is used to create a strong
and uniform magnetic field across the silicon ring. The
complete assembly is mounted within a hermetic can.
Zero Radial
Motion
at these
points
ν
C.G 18623
Figure 12.3 Primary Vibration Mode
© Copyright 2015 Silicon Sensing Systems Limited. All rights reserved. Silicon Sensing is an Atlantic Inertial Systems, Sumitomo Precision Products joint venture company.
Specification subject to change without notice.
DMU30-00-0100-132 Rev 1
Page 17
DMU30 Technical Datasheet
High Performance MEMS
Inertial Measurement Unit (HPIMU)
www.siliconsensing.com
ν
Resultant
Radial Motion
im
Fc
ν
ν
Fc
Pr
Applied Rate
Fc
el
Fc = Coriolis Force
ν
Silicon MEMS Capacitive Accelerometer
The accelerometer contains a seismic ‘proof mass’
with multiple fingers suspended via a ‘spring’, from a
fixed supporting structure. The supporting structure
is anodically bonded to the top and bottom glass
substrates and thereby fi xed to the sensor package
base.
ar
y
When the accelerometer is subjected to a linear
acceleration along its sensitive axis, the proof
mass tends to resist motion due to its own inertia,
therefore the mass and its fingers become displaced
with respect to the interdigitated fi xed electrode
fingers (which are also fi xed to glass substrates).
Air between the fingers provides a damping effect.
This displacement induces a differential capacitance
between the moving and fi xed silicon fingers which is
proportional to the applied acceleration.
Capacitor plate groups are electrically connected in
pairs at the top and bottom of the proof mass.
In-phase and out of phase waveforms are applied
by the ASIC separately to the ‘left’ and ‘right’ finger
groups. The demodulated waveforms provide a
signal output proportional to linear acceleration.
in
Having established the cos2 mode of vibration on the
ring, the ring becomes a Coriolis Vibrating Structure
Gyroscope. When the gyroscope is rotated about
its sense axis the Coriolis force acts tangentially on
the ring, causing motions at 45° displaced from the
primary mode of vibration. The amount of motion at
this point is directly proportional to the rate of turn
applied to the gyroscope. One pair of diametrically
opposed tracking sections, known as the Secondary
Pick-off SP section, is used to sense the level of this
vibration. This is used in a secondary rate nulling loop
to apply a signal to another pair of secondary sections,
known as the Secondary Drive SD. The current
applied to the Secondary Drive to null the secondary
mode of vibration is a very accurate measure of the
applied angular rate. All of these signals occur at the
resonant frequency of the ring. The Secondary Drive
signal is demodulated to baseband to give a voltage
output directly proportional to the applied rate in free
space.
Figures 12.5(a) and 12.5(b) provide schematics
of the accelerometer structure and control loop
respectively.
Sensing axis
Fixed support
C.G 18400
Figure 12.4 Secondary Vibration Mode
The closed loop architecture of both the primary
and secondary loops results in excellent bias, scale
factor and non-linearity control over a wide range
of operating environments and life. The dual loop
design, introduced into this new Sensor Head design,
coupled with improved geometric symmetry results in
excellent performance over temperature and life. The
discrete electronics employed in DMU30 ensures that
performance is not compromised.
Fixed Electrode 1
Fixed Electrode 2
Proof mass
(includes fingers)
C.G. 18613
Figure 12.5(a) Schematic of Accelerometer
Structure
© Copyright 2015 Silicon Sensing Systems Limited. All rights reserved. Silicon Sensing is an Atlantic Inertial Systems, Sumitomo Precision Products joint venture company.
Specification subject to change without notice.
Page 18
DMU30-00-0100-132 Rev 1
DMU30 Technical Datasheet
High Performance MEMS
Inertial Measurement Unit (HPIMU)
www.siliconsensing.com
88kHz reference
Electrode 2
Signal proportional
to movement of
proof mass
Out of Phase Square Wave
at 88kHz on Electrode 2
Sensing axis
Demodulator
Amplifier
Electrode 1
Low pass
filter
In Phase Square Wave
at 88kHz on Electrode 1
Output signal
C.G. 18540
Pr
el
im
in
ar
y
Figure 12.5(b) Schematic of Accelerometer
Control Loop
© Copyright 2015 Silicon Sensing Systems Limited. All rights reserved. Silicon Sensing is an Atlantic Inertial Systems, Sumitomo Precision Products joint venture company.
Specification subject to change without notice.
DMU30-00-0100-132 Rev 1
Page 19
DMU30 Technical Datasheet
High Performance MEMS
Inertial Measurement Unit (HPIMU)
www.siliconsensing.com
Pr
el
im
in
ar
y
Notes
Silicon Sensing Systems Limited
Clittaford Road Southway
Plymouth Devon
PL6 6DE United Kingdom
Silicon Sensing Systems Japan Limited
1-10 Fuso-Cho
Amagasaki
Hyogo 6600891 Japan
T:
F:
E:
W:
T:
F:
E:
W:
+44 (0)1752 723330
+44 (0)1752 723331
[email protected]
siliconsensing.com
+81 (0)6 6489 5868
+81 (0)6 6489 5919
[email protected]
siliconsensing.com
Specification subject to change without notice.
© Copyright 2015
Silicon Sensing Systems Limited
All rights reserved.
Printed in England 03/2015
Date 06/03/2015
DMU30-00-0100-132 Rev 1
DCR No. 710008599
© Copyright 2015 Silicon Sensing Systems Limited. All rights reserved. Silicon Sensing is an Atlantic Inertial Systems, Sumitomo Precision Products joint venture company.
Specification subject to change without notice.
Page 20
DMU30-00-0100-132 Rev 1