Challenge
The high-stakes environment of a luxury automotive exhibition in Düsseldorf presented several critical engineering bottlenecks. Unlike static warehouse deployments, an exhibition stage for a 2,000 kg vehicle must prioritize aesthetic fluidity and public safety without compromising mechanical capacity.
-
Rotational Eccentricity and Lateral Stability: A 2-ton vehicle possesses a non-uniform center of gravity (CoG). Rotating this mass at an elevated position (up to 1,500 mm) induces lateral torque on the scissor linkages. Standard lifts often exhibit “micro-sway” during rotation, which is unacceptable for high-resolution photography and the safety of the surrounding public.
-
Acoustic Emission Constraints: Trade show regulations in Germany enforce strict noise pollution limits, typically requiring equipment to operate below 60 dB. Conventional hydraulic power units (HPUs) often exceed these levels, necessitating a solution with advanced sound-dampening or a high-efficiency electric-drive alternative for the INTERNAL LINK: rotating stage platform.
-
Precision Synchronization and Motion Fluidity: The requirement for simultaneous lifting and 360-degree rotation demands a control system that can manage dual-axis motion without “juddering” or mechanical stutter. The rotation speed must be infinitely variable (0.5 to 3.0 RPM) to sync with choreographed DMX512 lighting sequences.
-
Closed Height and Floor Integration: To achieve a “seamless” appearance on the exhibition floor, the stowed height of the unit had to be minimized to avoid a bulky podium look. This required a high-capacity scissor design that could fold into a profile of less than 400 mm.
-
Public Safety Compliance (DIN EN 1570-1): As the stage operates in close proximity to thousands of attendees, it must feature redundant safety systems, including perimeter sensors and instantaneous emergency braking, to comply with the BGV C1 safety regulations for stages.
Solution
To address the precision and safety requirements of the Düsseldorf exhibition, a customized RS-2000-DUS rotating stage was developed. This unit integrates a high-rigidity scissor lifting mechanism with a low-noise, high-torque rotational drive.
1. Structural Kinematics and Scissor Architecture
The lifting foundation utilizes a dual-scissor linkage fabricated from Q355B high-tensile structural steel. The arm profiles were laser-cut to ensure a tolerance of ±0.1mm, significantly reducing the lateral play that typically causes “sway” at height. To achieve the 400 mm closed height requirement, the cylinders were mounted in a cross-axial configuration, allowing for a 1,500 mm travel range without increasing the base footprint. This rotating scissor lift stage ensures that the 2,000 kg EV is supported by a stable, non-deflecting platform throughout the display cycle.
2. High-Precision Rotation via Slewing Ring Bearing
The circular platform (3,500 mm diameter) is mounted on a heavy-duty internal gear slewing ring bearing technology This bearing is designed to manage high axial loads and tilting moments induced by the vehicle’s asymmetric CoG. The rotation is driven by a 0.75kW AC geared motor equipped with a Variable Frequency Drive (VFD). This allows for millimetric speed control, enabling the vehicle to rotate at ultra-low speeds (down to 0.1 RPM) with zero mechanical vibration.
3. Integrated DMX512 Control and Synchronization
The motion of the stage is managed by a centralized rotating stage platform controller based on the Siemens S7-1200 PLC automation platform. A specialized DMX-to-Analog converter was integrated into the control cabinet, allowing the exhibition’s lighting director to trigger lifting and rotation commands directly from the main lighting console. The PLC handles the “acceleration and deceleration ramping” to ensure that the transition from static to motion is visually seamless to the audience.
4. Low-Noise Hydraulic and Safety Systems
To meet the strict 60 dB noise limit, the hydraulic power unit was housed in a secondary acoustic-insulated enclosure and utilized a high-precision screw pump instead of a traditional gear pump. Safety features include:
-
Electronic Safety Trip Bars: Installed on the perimeter to halt all motion if an obstruction is detected under the platform.
-
Safety Leveling Outriggers: Four adjustable mechanical jacks on the base frame ensure the unit is perfectly level on the exhibition floor, preventing unintended gravitational torque on the slewing bearing.
-
Emergency Brake Integration: A failsafe electromagnetic brake on the rotation motor locks the platform instantly if power is lost.
