OMS 3 – Optical Sensor for Longitudinal Dynamics
Non-contact measurement – even on difficult and curved surfaces
The single-axis optical sensor system OMS 3 combines optical and inertial (IMU) measurement technology and is designed specifically for longitudinal dynamics. It measures speed and distance with a non-linearity of less than ±0.1% FS, even on low-texture and curved surfaces. Simply connect and measure – no need to wait for GPS or roll-in.
Speed up to 400 km/h / 250 mph
Angular Rates Y/Z
Distance (e.g. Braking Distance)
Pitch Angle
Acceleration X/Z
Many Other Calculated Parameters
Description
The OMS 3 optical sensor combines non-contact optics with inertial measurement technology in a compact system for longitudinal dynamics. Its one-dimensional optics deliver stable measurements even on surfaces with little texture or challenging surface properties. The sensor geometry tolerates measurements on curved surfaces, such as large pipes or roller coaster tracks. The OMS Race ECU processes the signals at 1 kHz with a signal delay of 3.75 ms and outputs them via CAN FD, CAN or Ethernet.
Features
- Proven spatial filter principle
- One-dimensional optics, optimized for longitudinal dynamics
- High dynamics thanks to 1 kHz update rate and 3.75 ms signal delay
- Parameterizable sensor fusion with three operating modes
- Output via CAN FD, CAN 2.0B and Ethernet
- Diagnostic data via CAN
- Compact OMS Race ECU, IP67
- Sensor and ECU individually exchangeable
- Long-life IR LED lighting
- Browser-based parameterization, no additional software required
Applications
- Longitudinal dynamics
- Brake measurement
- Tire performance
- Measurements on curved surfaces
- Indoor testing
- Land survey
- Rail and tram
- Roller coasters and amusement rides
- Mobile machines
- Motorcycle
- Industrial applications
OMS Race ECU: Compact, Robust, CAN FD
The OMS 3 works with the OMS Race ECU, which is also used in the OMS Race and OMS 7 Race. It measures 121 × 84 × 22 mm, weighs 270 g and is rated IP67. This allows it to be installed where water and strong vibrations occur.
Key Benefits of the Race ECU
- Compact and lightweight – about ¼ the volume and ⅓ the weight of the OMS 4 and OMS 7 ECU
- Robust – designed for high vibrations and harsh operating conditions, shock and vibration tested with profiles from Formula 1 teams
- CAN FD interface – fast data transmission at up to 8 Mbit/s
Three Operating Modes
- Optical-only mode – high-precision measurements with improved resolution and enhanced dynamics
- Optical priority mode – optical measurements combined with IMU-based validation for increased reliability and accuracy
- Advanced sensor fusion – fully integrates optical and IMU data for virtually noise-free signals
OMS 3 vs. OMS 4
Both sensors measure longitudinal dynamics without contact. Which one fits best depends on the surface, the track and the installation.
| Requirement | OMS 3 | OMS 4 |
|---|---|---|
| Longitudinal dynamics on a standard road, e.g. braking distance | ✔ | ✔ |
| Challenging surface properties | ✔ | limited |
| Curved, non-planar surfaces | ✔ | – |
| Purely optical measurement without IMU fusion | ✔ | – |
| Distance measurement on curved tracks | – | ✔ |
| Output via CAN | ✔ | ✔ |
| Output via CAN FD | ✔ | – |
| Output via Ethernet | ✔ | ✔ |
| Pulse output | limited¹ | ✔ |
| Unstable power supply with brief voltage dips | – | ✔ |
| ECU installation with high vibration | ✔ | limited |
| ECU installation exposed to water | ✔ | – |
| Compact, lightweight ECU | ✔ | limited |
| Low power consumption | ✔ | limited |
¹ One PPM output, unidirectional.
Technical Data at a Glance
| Specification | OMS 3 |
|---|---|
| Speed range | 250 or 400 km/h |
| Non-linearity | < ±0.1% FS |
| Optical resolution | ≈ 0.6 mm |
| Working distance | 300 ±150 mm |
| Angular rates (Y, Z) | ±500 °/s |
| Accelerations (X, Z) | ±20 g |
| Measuring frequency | 1,000 Hz |
| Signal delay | 3.75 ms |
| Interfaces | CAN FD / CAN 2.0B, Ethernet, digital I/O |
| Supply | 10 … 36 V, < 16 W at 12 V |
| Operating temperature | −25 … 50 °C |
| Protection class | Sensor IP68 (cable plugged in), ECU IP67 |
| Dimensions | Sensor 95 × 65 × 40 mm, ECU 121 × 84 × 22 mm |
| Weight | Sensor 390 g, ECU 270 g |
All data, order codes and drawings can be found in the data sheet.
Scope of Delivery and Accessories
The OMS 3 is delivered ready for use in a case: sensor, ECU, 5 m sensor cable, power, CAN and Ethernet cables, mounting tools and measuring tape. Cables in other lengths are available on request.
Various mounts are available for installation on the vehicle, such as a side holder, a towing eye holder and a wheel holder.
Part of an Integrated Measurement System
The OMS 3 can be operated simultaneously with the OMS 7, HMS and WVS. This creates a measurement system from a single source: synchronized data, one software platform, one point of contact. Longitudinal dynamics measurements can thus be directly linked with vehicle height, wheel kinematics or lateral dynamics.
Frequently Asked Questions about the OMS 3
What does the OMS 3 measure?
Speed and distance in the vehicle’s longitudinal direction, optically and without contact. For distance measurements on curved tracks, we recommend the OMS 4. The integrated IMU also provides angular rates around the Y and Z axes and accelerations in the X and Z directions.
How does the OMS 3 differ from the OMS 7?
The OMS 7 measures in two axes and therefore also captures lateral velocity and sideslip angle. The OMS 3 measures in one axis and is specialized in longitudinal dynamics, making it more robust on difficult and curved surfaces.
Is the OMS 3 suitable for braking distance measurements?
Yes. With a 1 kHz measuring frequency, a signal delay of 3.75 ms and a purely optical measuring mode, it is designed for braking distance measurements.
Can the OMS 3 measure on curved surfaces?
Yes. The sensor geometry tolerates measurements on curved surfaces, for example on large pipes or roller coaster tracks.
Does the OMS 3 need GPS?
No. The optical measurement works independently of GPS, so it also works indoors and in tunnels.
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Service-Hotline:
+49 641 972499-77
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