The multi-functionality of precision fasteners in robotics

Whether it is an industrial machine, prosthetic arm or a surgical robot, every fastening component plays a crucial role in ensuring good performance.

Here, Patrick Faulkner, Lead Engineer at Accu, explores the multi-functional uses of precision fasteners and components in robotic applications.

The importance of fasteners

Precision engineering fasteners are important for maintaining tight tolerances and accurate alignment of components in robotic systems, such as sensors and bearings. Even slight misalignment caused by loosened fasteners can increase wear and lead to poor movement accuracy, determining the overall success of the final design.

Knowing which fasteners are best to use is crucial in resisting vibration and supporting motion.

The expanding role of robotics

Industrial robots have been the foundation of modern manufacturing for some time now, enhancing productivity and efficiency and improving workplace safety. Often in the form of robotic arms, these machines come in various sizes, flexibility ranges and payload capacities to handle heavy workloads and repetitive tasks.

Today, the role of robotics extends far beyond factory floors. We are witnessing a rise in service robots, which are designed to assist with everyday tasks and improve quality of life. These range from automated vacuum cleaners in homes and offices to robotic surgical assistants capable of performing highly precise procedures. In healthcare, robotic prosthetics are restoring mobility and independence to users, offering greater functionality.

Advanced technologies are also driving innovation in mobile robotics, including wheeled delivery robots and aerial drones. These autonomous robotic systems are capable of navigating environments by themselves, using sophisticated algorithms and real-time mapping to move efficiently from point A to point B.

Another fascinating category is social robots, which are designed to interact with humans on an emotional and social level. By combining artificial intelligence with lifelike behaviours,these robots can provide companionship, support mental wellbeing and assist in educational or therapeutic settings.

Engineering fasteners in action

Using precision engineering fasteners and assembly hardware from Accu, TASKA, an innovator in prosthetic technology, engineered the world’s first water-resistant and multi-articulating prosthetic hand. This robotic innovation is designed to withstand the demands of everyday life, offering users enhanced flexibility and the freedom to perform daily tasks with greater ease.

Design was the main focus throughout building the prosthetic, with great consideration on delivering high functionality without compromising on aesthetics. Finding precision fasteners that were easily accessible was important not only for ensuring long-term reliability but also for supporting scalability.

A key goal in the design process was to keep the prosthetic as light as possible without sacrificing strength. TASKA achieved this by using stainless steel machine screws with pre-applied thread lock, pins and E-clips from Accu, which allowed for a compact and robust assembly that is highly reliable in different environments, including underwater.

The TASKA hand prides itself on being waterproof, which means every fastener has to be able to withstand frequent exposure to moisture and water. Accu’s stainless steel socket cap screws were chosen for their excellent corrosion resistance, ensuring long term durability. These socket cap screws are also available in a wide range of micro sizes (m1.6 to m2.5), allowing TASKA to meet tight tolerances.

Given that the prosthetic is used for everyday manual tasks, vibration resistance is crucial. To ensure fasteners remained secure over time, TASKA used nylon locking nuts and AccuLock screws (pre-applied thread locking), both of which are engineered to resist loosening under repeated motion and mechanical stress.

Different types of precision fasteners in robotics

When it comes to building high-performance robotic systems, precision engineering fasteners are responsible for securely connecting parts, enabling precise movement and maintaining stability. The type of fastener used depends on a variety of requirements, such as strength, weight, vibration resistance and the environment it will be used in. Most robotic assemblies rely on fasteners made from materials such as stainless steel, aluminium, titanium or polymers.

Stainless steel socket cap screws are widely used in robotics for their excellent strength and accessibility. They provide a high clamping force and can maintain structural integrity over time, even in demanding environments. On the other hand, polymer fasteners offer a lightweight alternative, which is particularly beneficial for robotic applications where reducing weight can increase speed. They also offer electrical insulation, which is essential in robotics in sensitive environments or those dealing with sensitive instruments.

Shoulder screws and bolts are a great example of components that enable motion as their smooth unthreaded shaft allows rotating parts to spin freely without loosening or wearing down. Often used to mount arms or bearings, their 'shoulder' offers far more precise tolerances than a traditional machine screw.

Where a robot experiences constant vibration, such as the joints or motors, nylon locking nuts are commonly used. These nuts maintain their hold under vibration and repeated cycles, making them ideal for securing gearboxes or structural parts.

When appearance is important, button head screws and bolts are ideal. Their rounded, low-profile heads reduce snagging and improve aesthetics while still offering great strength.

The capabilities of fasteners in robotics are endless, acting as an important component that ensures precision. Choosing the right combination of fasteners makes all the difference in how a robot performs.