Industrial Application: Shock Absorbing Elbow and Knee Pads

Existing Elbow/Knee Pad Designs 

Industry is a field that is need of constant equipment updates due to new challenges and dangers alike. Among these equipment, the most common to be ignored are elbow and knee pads. The current design of elbow and knee pads existing in the market is based on foam padding. Foam padding contains air, which acts as the shock absorbing material. Once the air is compressed, there is very little that stands in the way of the approaching object and the knee of the person, meaning the user is at great risk to forces greater than the threshold of the pad. To counter this, gel pads are introduced, with the addition of gel in the already existing foam padding. This gel provides extra shock absorbing capabilities however, in the case of torn elbow/knee pad, this gel will leak out rendering the knee pad useless. Besides the disadvantage mentioned, when gel is added to the elbow/knee pad, it increases the size of the pad, making it bulky as well as heavy. 

The New Elbow/Knee Pad Design 

The design of elbow/knee pad must be strong enough to withstand harsh working environments and strong forces yet be lightweight and compact for a comfortable experience. With these aims in mind, the spines of the hedgehogs can fit the design perfectly. Hedgehog spines can withstand considerable incoming damage as they are able to protect the hedgehog’s body from falls up to 10 meters high. Spines are able to perform this action due to the presence of air pockets within each spine, providing extremely high strength to weight ratio and thus, able to prevent the spines from breaking and buckling. From literature review gathered, hedgehog spines under humid conditions can withstand forces of 8 Joules even after multiple collisions. 

Replacement Material for Spines 

The spines of hedgehogs are made of a material called keratin. Since keratin is a biological material and therefore difficult to gain access to, a suitable alternative must be utilized instead. The material needs to be lightweight, durable and low cost, so people who work in the industry can easily afford it. Acrylonitrile butadiene styrene (ABS) fits the criteria of material required. It has high impact resistance, easy to machine and thermoform [1], Figure 1.

Figure 1. ABS Material for Hedgehog Inspired Elbow/Knee Pads

Viability of the Design 

The viability of every product is based on the three pillars of sustainability, which are economic viability, environmental sustainability and social feasibility. The product is economically viable since it is made of cheap materials. It has environmental sustainability due to the fact it has very low hazards associated with it. And it is socially feasible since the design is basically done to help people working in the industry, to improve their safety and comfort in the working environment. 

Funding for the Project

Even though the cost of the ABS material is cheap, the designing, modeling and construction of the prototype and eventually the final product will require considerable cash input. Due to the fact this design is done by a team of students, who do not have any organization backing them, as well as the fact that funding is a challenge faced by every engineer and inventor, the project will be funded by the crowd. In order to make the usual crowd aware of the project and its implications on the safety of the workers in an industrial environment and even day to day activities such as driving a motorbike or riding a bicycle, a crowdfunding platform will be utilized. There are many crowd funding platform, however the most popular at the moment is “Pozible”. All the details about the project, including the release date will be provided to the crowd. This use of such platform not only allows for collection of funds but acts as a free advertising zone and also as a direct feedback zone on the product itself. 

Biomimicry and Inventions

Application of hedgehog spines for production of elbow/knee pads is the not first time an engineer or inventor has taken inspiration from nature to find solutions to existing problems. One of the most famous invention that was inspired from nature is the road stud reflector. During night time when light is shined onto a cat’s eye, it reflects the light back given the eyes a glowing effect, Figure 2. It also reveals the location of the cat. Similar effect is used for road stud reflectors we now see on all the roads, Figure 2. Road studs reflectors have the same working principle and are one of the safety requirements for all roads now. Another example is beak of the bird called kingfisher. Japanese inventor studied the design of kingfisher and came to the conclusion it has the highest drag reduction possible due to the design of its beak. They utilized the kingfisher beak design to the design of the beaks of bullet trains. There are many other inspirations from nature that have led to major inventions throughout the world. Biomimicry is a major aspect of engineering and invention and must be studied and applied whenever possible. The use of biomimicry leads to an overall better design that be cost effective and environmental friendly. 

Figure 2. Roads Studs (Top) and Cat Eyes (Bottom)

References 

[1] “Outstanding impact resistant low cost plastic, easy to machine and thermoform,” p. 2355, 2016.