What are the Best Materials to Design and Build Durable Robots?

Building robust robots starts with using the strongest materials available. Today, engineers can design durable robots capable of incredible things, from walking like a human to surviving the harsh environments of other worlds. Many wonder what makes these feats possible.

Robust robots are a combination of brilliant design and highly durable building materials that are also suited to the robot’s unique purpose. There is a strategy behind the materials that robotics engineers ultimately choose to use for their robots. From industry-standard metals to innovative synthetic materials, these materials are the best for building and designing durable robots.

How Engineers Design Durable Robots

Many characteristics and components go into creating durability in robust robots. Engineers have to strategically design a robot for durability in addition to choosing the right materials for it.

It is important to remember that “durability” often means something different from one robot to another. For some robots, durability means being able to stand up to harsh climates. For other robots, it means being able to take heavy falls without breaking. Sometimes durability even means being able to move freely without parts breaking or malfunctioning.

A great example of this is one unique robot from MIT that can perform maneuvers like running, jumping, ducking, and flipping, all on four thin metal legs. For this robust robot, the engineers needed materials that were lightweight but capable of standing up to the impact of doing things like jumps and backflips.

This is a perfect example of the role that inner parts play in the durability of a robot. The outer shell needs to be durable enough to protect the robot’s components. However, every little part inside the robot needs to be durable in its own right so the robot can function properly. Certain parts can add strength and resilience to robots when made with durable materials themselves.

As robots take on more important roles in fields like exploration and medicine in the years ahead, durability will be a major priority. When engineers design durable robots, they have to find the best combination of materials to meet as many of the robot’s needs as possible.

Metals: Key for Robust Robots

When most people think of a tough and durable material, metal is one of the first things that comes to mind. That’s because metals have long been among humanity’s strongest building materials. Different metals are ideal for different things, though, and some metals are more resilient than others. It is also worth noting that not all metals are good for building robust robots.

By far the most common metal used to design durable robots and make them a reality is steel. It is usually an affordable building material and easy to find. Engineers can use various processes to customize the properties of steel to better fit their needs.

For example, one common process used to make steel more durable is heat treating. There are numerous types of heat treatments for all kinds of metal, but hardening is particularly common for robotics steel. Tempering is also useful for steel, making it stronger and less brittle. In general, steel containing a high amount of carbon is best for durability since the carbon helps the steel stand up to heat treating.

In addition to the many types of specialty steels used to build robust robots, other metals can make great choices for durability as well. While aluminum is less strong than steel, it is also much lighter and easier to shape and work with. So, aluminum alloys are a common choice in robotics. Aluminum doesn’t rust and is also non-magnetic, both of which are valuable features for many applications.

Additionally, alloys of various other metals are often used for niche purposes in robotics, such as brass and bronze. While these alloys are more expensive than steel, they do have unique features that can boost durability in certain applications, including corrosion resistance.

Plastics: Good or Bad for Durability?

Plastics are an interesting topic when it comes to robust robots. While plastics cannot compete with metals in terms of sheer strength and heat resistance, they do often have valuable features at an often affordable price. Plastic is easy to shape and mold as desired. Plastics scientists can create specific types of plastics today that are made for virtually any unique circumstance. However, many plastics are not ideal for durable robotics. They tend to suffer from brittleness, lack of heat resistance, and sensitivity to certain chemicals.

Nonetheless, there are still some plastics that are great for those who want to design durable robots. Depending on the unique circumstance, certain plastics can be great for specific parts of a robot or areas of its structure. This is especially true in cases where flexibility is needed since many plastics can bounce right back into shape after being deformed. When used in the right way, plastics can be great for durability.

Plastics that are commonly used in durable robots include polycarbonate, ABS plastic, and PVC, among others. Polycarbonate is extremely popular in engineering and many will know it from its use in bulletproof windows. It can withstand up to 10,000 psi of pressure and is extremely difficult to break. PVC would be a more durable alternative to plexiglass in a robot that needed a transparent window on it.

ABS plastic and PVC are both commonly used in consumer products, such as LEGO bricks and plumbing pipes respectively. ABS plastic is rigid without being prone to shattering, so it is strong enough for many robotics applications. PVC is a good affordable material when it comes to durability. It is fairly impact-resistant and easy to machine into specific shapes.

Composites and Other Materials

Composites are a broad category of materials. Generally, a composite is any material that is a combination of two or more different materials. The goal when creating a composite is to combine the properties of the component materials to make one new material that has certain desirable characteristics.

Fiberglass is a great example. It is a composite of glass and plastic resin, combining the two to create a material that is strong but also flexible. Fiberglass is a great material for building robust robots.

There are many different composites that engineers use when they design durable robots. Usually, only a few types of composites are commonly found in robots, though. These include fiberglass, carbon fiber, and even wood composites. While wood might seem like an odd choice for durability, it actually has some interesting properties.

Wood

There are dozens of different species of wood used in engineering, varying in their unique characteristics. Wood is usually very affordable and easily accessible, plus it is extremely easy to work with and shape as needed. It is very strong, although only along the grain. The grain is the direction that the thin lines seen on wood go in. For example, on a long piece of lumber, the grain will be along the longest edge.

Wood becomes much more brittle when force is applied perpendicular to the grain. Additionally, since wood is a natural material, inconsistencies and quality defects are common, such as knots or uneven grain.

Carbon Fiber

Carbon fiber is a general term used to refer to the many varieties of carbon composites. Carbon fiber contains carbon atoms mixed with another material, such as plastic resin. These composites can be incredibly durable, although they are much more expensive than most other materials and are more dangerous to work with. Protective equipment must be used when manufacturing, cutting, drilling, or otherwise interacting with carbon fiber. It can be dangerous to both touch or inhale, so caution is crucial.

However, for many engineers, the hazardous characteristics of carbon fiber are worth the trade-off for durability. It is extremely strong while also being lightweight and stiff. Carbon fiber composites have strong chemical resistance and heat resistance, as well. Their combination of durability properties and low weight make carbon fiber composites especially popular in aerospace applications.

Kevlar and Nylon

Kevlar and nylon are both synthetic materials used in various applications where durability is a priority. For example, kevlar is commonly used in bulletproof vests. Both nylon and kevlar are often known for their fabric applications, but they can be extremely useful in robotics, as well. Kevlar is strong and resistant to high temperatures at both hot and cold extremes. So, kevlar makes a great exterior covering to protect robust robots from hostile environments.

Nylon is extremely strong and is capable of withstanding up to 12,000 psi of pressure before breaking. In its solid form, it is often used for making a variety of structural components in robots. It is flexible and engineers can even use injection molding to shape solid nylon parts.

Building Durable, Robust Robots

The world’s most durable robots are feats of engineering and design. Building robust robots that can survive in environments like the surfaces of other planets requires collaboration among materials scientists and engineers in numerous fields. In order to design durable robots, the right combination of strength, flexibility, and environmental resistance needs to be identified. The perfect mix of materials inside and out can allow any robot to stand up to any challenge that comes its way.