Acoustic quality, vehicle dynamics and stability, and driver comfort play an increasingly important role in the development of new chassis and suspension systems – both passive and active. Noises in suspension components can cause customer dissatisfaction and lead to high warranty costs and are difficult to diagnose especially on historically-used, noisy hydraulic test rigs. The MB Dynamics’ Suspension Component Test Rig (SCTR) enables dynamic simulation of real road excitations and synthesized waveforms, performing industry-standard Force-Velocity and Force-Displacement tests and low speed friction tests, and assessing other NVH and structure-borne noises for comprehensive performance characterization and sound and vibration analyses on a wide variety of chassis components.
Our innovative technology uses a combination of dynamic force generation using acoustically-quiet linear motors combined with quiet, no-stick-slip air bearings for motion creation – augmented by air springs for compression and curb-height loading. High-frequency closed-loop control of the dynamic response of servo-motor acceleration/force systems presents unique challenges. MB’s past work with dynamic control of servo-motors has shown that the classic servo-motor control systems, using position encoder feedback for displacement control, are unsuitable for use where high-frequency controlled dynamic acceleration/force response is also required. This is because a position encoder cannot deliver the resolution required to control high-frequency road load data with up to 50 Hz content. This problem is especially acute above 20 Hz. Other strut/shock tests require even higher frequency content. MB has developed a hybrid control system using both position encoder and accelerometer / force feedback to achieve accurate high-frequency dynamic response. This control strategy is proven technology and is employed in the SCTR rig.
Download Suspension Component Test Systems Data Sheets
Suspension Component Test Rig Data Sheet
Airbag Sensor Test System (MB ABSTS) Data Sheet
Noise Characterization, NVH, & Performance Characterization
- Strut Pop
- Rebound Noise
- Sway Bar & Bushing Noise
- Leaf Spring Noise
- Noises in Active Dampers and Mounts
- Stick/Slip and Squeak Noise
- Road Load/Time History Replication
- Force/Displacement
- Force/Velocity
Specifications
- Peak Dynamic Force (100% of theoretical motor rating): >17kN Pk Instantaneous (uncooled)
- Peak Dynamic Force (de-rate for reasonable operation): >14kN Pk Instantaneous (uncooled)
- Continuous Static Force: >4kN Pk Sine Test
- Static Support Force (Air Spring Actuator): >8kN Continuous
- Peak Velocity (no payload): 4m/s
- Peak Velocity (10kg payload): 4m/s
- Linear Motor Actuator: acoustically quiet, high-fidelity dynamic waveforms
- Air Spring Actuator: high compressive force, more durable than air cylinder
- Quiet: test equipment does not mask test item noises
- Background Noise: <2.0 Sones or 35 dBA, 13 Hz 1.0g pk 3mm p-p sine motion, no test item mounted
- No Hydraulics: safe, no high pressure oil, no environmental issues
- Low maintenance: no seals, servo-valves, hoses to replace
- Air Bearings: friction-less motion, non-contacting, no wear, no striction, no balls or rollers, low noise
- Control Modes: acceleration, displacement, force (static and dynamic); road load time history, PSD random, sine, triangle, square, synthesized waveforms
- Time History Force Accuracy: typically <5%, Response vs. Target
- Displacement: 205 mm p-p between stops
- Control Frequency Response: DC to 100 Hz, rolls off to 200 Hz
- Encoder: Resolution, 1×10(6) pules/mm 1V p-p Sine/Cosine analog, incremental
- Load Cell: interface Model 1010, 12.5 kN or 25 kN, tension & compression, shunt calibration, eccentric load compensation, performance to 0.03%, safe overload, ±300%(optional)
- Analog signals available: acceleration, velocity, displacement, force, motor current proportional to dynamic force
- Motor-controlled height adjustable crosshead
- Hinged safety guard (Lexan) around test item for see-through viewing
- Dimensions: 1.56m x 1.56m x 2.91m (Safety guard)
- Max test item height: 1000mm
- Test space width between columns: 1050 mm
- E-STOP: at Rig and at operator console