Marine › Motion Detecting Unit
Motion Detecting Unit — ship motion turned into decisions
Kjaerulf Pedersen a/s developed the MDU to digitise ship motion in real time: pitch, roll, dynamic trim, list and motion intensity — 100 measurements per second, processed onboard and stored internally for 4–5 months. Crew-installable, owned outright with no subscription, running 24/7.
From motion data to operational decisions
A vessel moves constantly — but without measurement, that motion is experience and estimate. The MDU turns it into data the bridge and the office can act on.
The MDU is installed by the vessel's own crew: a standalone system with 1–3 motion sensors, no structural modification and no external service visit. It runs autonomously from day one, 24/7.
The system samples vessel motion 100 times per second — pitch, roll, dynamic trim, list and motion intensity — and processes the data onboard with no third-party dependency. Everything is stored internally for 4–5 months; the data stays on the vessel.
Combined with vessel speed, fuel flow, draft and depth from existing onboard systems, motion data becomes the foundation for decisions on trim, route, speed and cargo operations — live on the bridge and in post-voyage review.
What the MDU does for your vessel type
Early identification of parametric, synchronous and resonance roll — before conditions exceed the limits of lashing systems and container stowage.
Cargo shift risk assessment, hull stress documentation in heavy weather, and operational decisions when roll phenomena develop.
Wide beam and low GM make these vessels particularly sensitive to parametric roll. Motion data supports cargo securing verification and stability decisions.
Motion within defined limits is an operational precondition: crew transfer windows, DP integration, cargo transfer operations.
Route optimization for passenger comfort, stabilizer performance verification, and sea-keeping documentation.
Real-time motion awareness for the bridge, and motion documentation for mission planning and post-mission analysis. Sensors for defence →
The numbers behind the system
| Sampling | 100 measurements per second |
|---|---|
| Measurements | Pitch, roll, dynamic trim, list and motion intensity |
| Sensors | 1–3 motion sensors — KP's own IMU-based motion sensing |
| Processing | Onboard, with no third-party dependency — the data stays on the vessel |
| Storage | 4–5 months onboard |
| Integration | Modbus / RS485; combines with vessel speed, fuel flow, draft and depth from existing onboard systems |
| Operation | 24/7 autonomous |
| Installation | Crew-installable — standalone system, no structural modification |
| Ownership | Owned outright — no subscription |
In service across the world fleet
The MDU is in service on more than 200 container and tanker-class vessels, running 24/7 in commercial operation.
The system is bought and owned outright — no subscription, no external dependency for daily operation.
Motion data is processed and stored on the vessel — sharing it is the owner's decision, not a platform requirement.
The sensor behind the system
The MDU is built on the same motion technology as the KPM100 digital inclinometer — roll, pitch, yaw, acceleration and angular velocity in real time over Modbus RTU. Need the sensor for integration in your own system rather than the complete onboard platform?
KPM100 — Motion Analyzing Sensor →Frequently asked questions
What does the MDU measure?
Pitch, roll, dynamic trim, list and motion intensity — sampled 100 times per second and processed onboard. Combined with vessel speed, fuel flow, draft and depth from existing onboard systems, it gives a complete picture of how the vessel behaves in the conditions it meets.
How is the MDU installed?
By the vessel's own crew. The MDU is a standalone system with 1–3 motion sensors, requires no structural modification, and runs autonomously 24/7 once installed — no external service visit needed.
Where does the data go?
It stays on the vessel. Motion data is processed onboard with no third-party dependency and stored internally for 4–5 months. The system is owned outright with no subscription — sharing data is the owner's decision.
Can the MDU warn about parametric roll?
Yes — early identification of parametric, synchronous and resonance roll is one of the MDU's core tasks, so countermeasures can be taken before conditions exceed the limits of lashing systems and cargo securing.
Does the MDU integrate with our existing systems?
Yes — over Modbus / RS485. The MDU combines its motion data with vessel speed, fuel flow, draft and depth from the systems already onboard, and presents the result live on the bridge.
What is the difference between the MDU and the KPM100?
The KPM100 is a motion sensor for integration in your own system — roll, pitch, yaw and acceleration over Modbus RTU. The MDU is the complete onboard platform built on KP's motion sensing: measurement, onboard processing, storage, bridge display and alarms in one system.
See the MDU on your vessel type
Tell us your vessel type and operation — and we will show you what the MDU would give your bridge and your office.