Page Comparison

Based on the research done in the previous section, it was evident that the user interaction would be much easier and streamlined with the compressed air struts compared to the 2 bar linkage system.

To open the trunk (if compressed air struts are used) the user would merely need to unlock the trunk latch and lift the trunk. From there the compressed air struts will prop the trunk open and keep it open. To close the trunk the user merely needs to pull down on the trunk panel and lock the latch.

In contrast to this, the 2 bar linkage system would require the user to unlock the trunk latch, lift the trunk and then slightly lower the trunk to engage the “Bird’s Mouth” Lock. To close the trunk the user would need to raise the trunk panel slightly to disengage the “Bird’s Mouth” Lock before closing the trunk. This process may not be intuitive and is cumbersome.

As can be seen in the previous section, there were notable concerns with the 2 bar linkage system.

From the basic assembly created (which did not account for the force of gravity), it was hard to verify if the “Bird’s Mouth” lock could easilybe engaged. There were some cases where the top bar may not translate diagonally and could instead rotate. This would not properly engage the “Bird’s Mouth” lock and more testing would be required for this.

In addition, there was a concern in the closing motion. Without the force of gravity being accounted for in the basic assembly, it was hard to verify if gravity would be enough to cause the bottom bar to naturally fall down (remember it is pin connected to the top bar) and rotate, thus causing the whole 2 bar linkage to fold properly as the trunk is lowered.

To conclude, it was difficult to determine if the ideal motion of the 2 bar linkage would happen in reality and if it didn’t would require even more user input to make the entire linkage system close properly. More testing would be required (likely a SolidWorks motion study, but this seemed to be incompatible with the slot mate used to define the pin connection between the bars AND/OR creating a scaled down version in real life) and this would complicate and lengthen the implementation process.

On the other hand, basic hand calculations were used to verify that the two compressed air struts would be enough to support the trunk panel (in fact just one compressed air strut was shown to be enough) and that a user could easily close the trunk (in accordance with OSHA guidelines for allowable pulling forces one can exert)

If the 2 Bar linkage system were to be implemented, it would need to be manufactured as well. While the geometry would be basic, there would still need to be time allocated to manufacture the parts as well as assembling them together.

On the other hand, the compressed air strut would be bought, and the only time required would be the shipping time. In addition not needing to manufacture it in house would free up some of our manufacturing resources. Important to note is that the compressed air struts were also reasonably priced (approximately $63.00 CAD for a set of two from McMaster-Carr), thus price was not an issue, in this case.