The active seat features two liquid-filled plastic sachets (fluid bubbles) that are incorporated under the seat cushion. The bubbles are alternately filled and emptied thus gently moving the spinal column of the person sitting in the seat in order to relieve tension, stiffness, fatigue and backache.
The entire active seat system consists of the following components
Two liquid-filled plastic sachets (fluid bubbles) are integrated in the seat upholstery. These bubbles are uniformly filled when at rest. When the active seat is switched on, a pump is activated that empties one bubble and completely fills the other so that the seat surface is raised on one side. This status is maintained for approx. 10 seconds. The bubble is then emptied to the mid-position. After a renewed pause of approx. 10 seconds the bubble is completely emptied and the other bubble completely filled.
This process ensures that the pelvis is continuously tipped slightly resulting in movement of the lower spinal column. The muscles work permanently (as when walking) and do not suffer from fatigue. The body remains relaxed.
When at rest, both fluid bubbles are approx. 15 mm high. When the system is active, the height changes between 0 and 30 mm. Although the bubbles are incorporated under the seat upholstery no elevation in the seat surface can be noticed when the seat is not subject to load.
The active seat can be activated as from ignition lock position 1 (terminal R). After switching off, the pump continued to run until both bubbles are in the mid-position.
The push buttons for operating the active seats are integrated in the centre console switch centre.
The line to the control unit for the active seat is switched to low (ground) for 30 ms by pressing the corresponding push button in the switch centre of the centre console. The control unit activates the active seat and also switches the line to low (ground) for 30 ms. The function LED in the push button is then switched on.
Feedback does not take place and the function LED remains off if the line to the control unit for the active seat has a break or if there is a fault in the active seat.
No feedback is sent by the control unit when the active seat is switched off.
The pump unit contains the following components:
The fluid bubbles are filled with a water-glysantin mixture. They are connected to the pump unit by means of plastic hoses. The pump unit and fluid bubbles must be replaced together in case of repairs.
Control units that control the pump unit are provided for the driver's and front passenger's seat. The control units are connected to the P-bus. The corresponding coding as to whether the control unit operates the driver's seat or the front passenger's seat takes place via Pin 5 (signal name COD) at the 6-pin plug connector of the control unit. The pin in the control unit on the front passenger's side is connected via a line to vehicle ground
The control unit for the driver's seat contains an acceleration sensor that registers the transverse acceleration of the vehicle. Operation of the active seat is temporarily interrupted at very high transverse acceleration levels.