We take an exclusive look at the shaker systems Johnson Controls Automotive Seating has available for use during seat development in Plymouth, Michigan
In addition to the two large sled labs at its Plymouth, Michigan test facility (see ATTI, March 2015) Johnson Controls Automotive Seating also has four shaker systems available for use during seat development.
In the vibration durability lab, as in the sled labs, test methods and specifications are being aligned across the company’s five global test centers. “We have recently taken delivery of a new type of water dummy that was developed in Europe by the Recaro product group,” offers Ryan Burkhardt, chief engineer of testing operations, by way of example (see pic, above). “We’re now looking to use the same water dummy in all regions.”
This lab (below), which contains the smaller of the two available 6DOF shaker tables, has had recent upgrades to its sound damping; this has brought the ambient level down by 15dBA when it runs it’s now about 40-42dBA. Two rows of seats can be mounted on the table, which runs recorded road data files. The rig itself is a Team-MTS hybrid, with the actuators and table built by Team and control systems by MTS. The same controls are used for both 6DOF shaker labs so that the two can share files.
In a lab close by is the ‘Comfort MAST’ the second 6DOF table, this time human-rated. Johnson Controls recently upgraded all of its hydraulic controls with the same controls as in the other lab. The pressure from each actuator can now be monitored so that it can be kept safe at all times, which is imperative when running with human occupants (this flexible shaker can also be switched to durability mode and run the same tests as the smaller 6DOF rig). The large table can handle almost a full vehicle buck three row sets for comfort simulation ‘ride and drives’. Here the focus is on transmissibility studies how much energy is going into occupants.
The remaining rooms in the NVH lab complex include a sound room for objective noise measurements. This features an MB Dynamics shaker system and a hushed 19-20dBA ambient noise level. “We can put a product in here, shake it, record the BSR (buzz, squeak and rattle) and quantify it,” explains Burkhardt. “We can record the operational sound on tracks and recliners and quantify those sounds.” The shaker currently offers vertical pitch and roll, but a possible future upgrade to 3DOF would bring it into line with its sister laboratory.
Meanwhile the H-point (seating reference point) lab plays close attention to this key seating design element. H-point studies are carried out and detailed position setups for sleds determined. Five FARO arms and two laser scanners mean that the technicians can scan a complete seat outline and compare it to the CAD data, providing information to seat development on where the design needs adjusting to match the customer’s requirements.
February 26, 2015
