Why We Research WIDFIX CUSHIONS

During the development of Widfix, we found that the ISOFIX anchors could push forward after installation. This caused some safety seats not to fit properly against the car seatback, leading to instability. To solve this, we created two types of cushions:

  1. Comfort Cushion: This is for forward-facing car seats and booster seats. It increases the contact area, providing better back support and a more comfortable experience for children.
  2. Mini Cushion: Smaller and designed for rear-facing car seats, this cushion helps with stability without affecting seat rotation or angle adjustments.

Figure 1: Comparison
Figure 2: The Comfort Cushion
Figure 3: The Mini Cushion

We tested the Comfort Cushion extensively with children of different ages and sizes, focusing on booster seat users. The first version, tested with a 110 cm tall Taiwanese girl, didn’t offer enough head support for taller children. We also found that European children, who have different head shapes, felt discomfort. After several design improvements, we developed a curved shape that adapts to different body types. We used high-density, slow-rebound memory foam for the best support and comfort.

Additionally, we addressed the issue of some vehicle seatbacks protruding near the door. The Comfort Cushion design helps reduce this discomfort, especially when Widfix pushes the seat towards the vehicle door area.

Figure 4: Diagrams of the prototype designs.
Figure 5: Feedback from children on the different cushion designs.

The Mini Cushion is specifically for rear-facing safety seats. It is small and firm, allowing easy seat rotation and angle adjustments. We refined its design several times, using high-density foam to ensure stability and impact resistance. It has passed all impact tests successfully.

Figure 6: Different Mini Cushion prototype shapes.
Figure 7: Initial testing with harder EVA foam for the Mini Cushion, which proved too difficult to install, so it was discarded.