Biomimicry: Army Ants
Name: Visagan a/l P. Arudselvan
This project aims to solve one of the issue faced in pedestrian bridge design, which is flexibility. By studying on the anthropometrics of the army ants, which build bridges using it owns bodies, new structural members are identified and formed based on features of the ants itself. Using this conceptual design, the forces acting on the bridge is studied on.
Description of the Study
As more land gets developed overtime, many across rivers, hills and even major highways, structures are needed to bridge the gap between two areas. However, most of the bridge designs today have no moving parts and remains in place until the structure fails on its own or is demolished for a solid reason. This prevents the bridge from being downsized, modified easily or removed and used elsewhere, although pedestrian traffic demands across it may vary or cease completely.
To add on, in the event of the bridge being damaged by a hard impact, seismic events, live loads being too heavy and all other possibilities, the bridge will become dysfunctional and may be closed of for weeks/ months depending on the severity of the damage. Large quantities of materials will be used in the process as there tend to be a domino effect, where a single point of impact will cause a larger surface area to become damaged ranging to multiple connection systems within the structure itself to fail and risk collapsing.
Therefore, to adapt and have strategies to factor this problem is essential to ensure well connection and smooth flow of people from one side to the other that would lead to these areas to thrive.
Army ants is chosen as an inspiration to bridge design due to their natural instinct in building bridges. ). Once food supplies become limited, they tend to search new grounds for foraging to ensure the population continues growing. . The bridge starts at the short path and eventually moves to a longer path. Worker ants will become sequested (stationary) to allow movements above them. More ants will become sequested gradually to form a longer bridge until the “cost-benefit” trade off is met. These ants forming the bridge will use their bodies to connect to each other and easily dismantle it when the army ant population has crossed it.
To traverse difficult terrains, ants grip the bodies of others with 4 main features: mandible, tarsal claws, arolia and the adhesive pads of tarsi forming chain like ant bridges. These features either are used to grip each other or to reduce the friction between ant bodies. This similar concept is used as a guide in designing the bridge for pedestrian purposes, where basic structures will either hold on to other members or increase the grip between members itself.
It is hoped that someday, such a design can be used in the event of natural disasters or army warfare to cross over long distances. It is also hoped that more civil engineers in the future will study on this technique and make it a reality.
Once food supplies become limited, they tend to search new grounds for foraging to ensure the population continues growing.
The bridge starts at the short path and eventually moves to a longer path. Worker ants will become sequested (stationary) to allow movements above them.
These ants forming the bridge will use their bodies to connect to each other and easily dismantle it when the army ant population has crossed it.
Structural/ Biological Properties Of The Ant Used In Building The Bridges
Sharp teeth and dense bristles combined with a mandible capable of gripping high force.
Tarsal Claws At The Legs Of Ants
Angled at 56 degrees and 75 degrees to prevent it from slipping. Increases the grip when building bridges.
Adhesive Pads Of Tarsi
Prevent friction and ensures a tighter grip between ants.
Arolia On The Tip Of Their Legs
Further enhances grip between members.