Small mechanisms – like latches and hinges – not only contribute to the performance, ergonomics and security of larger applications, they also have the power to make a big impact on the end-user experience.



People often like to talk about how digital our world is becoming. They point to the smart wireless devices and 5G networks that give us 24/7 access to digital content and tools that have become essential to daily life.

Nevertheless, we constantly interact, thousands of times a day, with the physical world. Systems, equipment, machines and devices ranging from automobiles and ATMs to storage units, lighting fixtures and appliances are manipulated — opened, closed, shifted, adjusted, locked and unlocked — with little conscious thought by most people as to how the mechanisms that provide access and control create the “touchpoint” experience we often take for granted.

Whether it’s effortlessly operating the seatback and tray table on an airline flight, or just slightly adjusting the card reader terminal at a convenience store checkout to enter a PIN, small access hardware mechanisms play a vital role in how the commonplace tools and devices we interact with every day operate in a smooth but functional manner.

Small mechanisms not only contribute to the performance, ergonomics and security of larger applications, but they also have the power to make a big impact on the end-user experience. Whether it’s a hand-operated latch used to access a glovebox or a counterbalance hinge that holds open a heavy engine hood, the end-user experience must be seamless and intuitive to create a positive perception of quality for the person interacting with the equipment.

For equipment manufacturers, however, scaling this experience is no easy task. No matter what type of device or system they build, if it requires physical human interaction, manufacturers must learn how to harness the power of small mechanisms to meet the functional needs of their access applications. Smart design and an appreciation for ergonomics can help equipment manufacturers scale these mechanisms with efficient, repeatable manufacturing to ensure that the end-user experience is the same — every time.

Engineering User Experiences


The role and value that smaller mechanisms can provide is based on how they can be used to engineer and define the functional experience of the end user. The simplest devices — hinges, latches, locking mechanisms, switches — can be selected for specific properties that add ease of use, ergonomic efficiency and a sense of functional quality and sophistication to many different applications.

These smaller mechanisms can play a critical role in optimizing each user’s experience of a device. For example, a hinge can change the angle on a self-service kiosk at a convenience store or sandwich shop to make it easier to use. Designers must choose the right type of hinge to make it easy to change the angle of the touchscreen, while also holding that same screen in place as the user taps on various icons to complete their order.

A positioning hinge is an example of the type of simple, yet well-engineered, mechanism designers can use to fulfill ergonomic requirements and influence how end users perceive the quality of their applications. These can include:

– Holding doors open or closed and moving panels securely into position without secondary supports or additional components.

– Creating an intuitive, zero-drift motion so that, when a door or cover is opened, it holds a user-defined or predefined position securely, with one motion.

– Eliminating additional components (such as gas struts) or routine maintenance (tightening screws to maintain hinge resistance), thereby lowering overall costs.

– Providing a smoother, more substantial feel to opening and closing action, or to eliminate vibration.

Mechanisms like positioning hinges that change — or elevate — the user’s perception can be applied in many ways. Consider the airplane tray table. Seating designers must use extremely lightweight plastic components in these applications to help airlines reduce fleet weight and conserve fuel.

However, a tray table that just flops down upon opening can lead a passenger to question the quality of the aircraft itself. Using a constant torque hinge with a factory-set level of resistance, the passenger can lower the tray with just the right level of force, making the tray feel more substantial and improve the passenger’s confidence in the overall quality of their environment. In addition, constant torque hinges designed and manufactured with high-quality materials retain the desired resistance after thousands of flights, without requiring maintenance or parts replacement.

Convenience, Safety and Efficiency

Choosing the appropriate small mechanism makes it possible to provide the desired function without added effort by the end user, while also helping to avoid complicated designs or added space.

Consider the two common storage compartments in the front of the car: the glove box and the center console. How the person in the driver’s seat accesses and uses those two compartments can be very different.

On the glove box, the latch is often located in the center of the door. In some cases, it is a simple latch; in others, it is secured with a lock. To open the locked door, a user would have to turn off the car and remove the key from the ignition. In both instances, they have to lean over and reach for the lift latch — something they often can’t safely do while the car is in motion or stopped at a traffic light.

The simplest design fix would be to move the latch all the way to the left of the box, to reduce strain and create a more ergonomic user experience. A customized rotary latch with multi-point contact supplies two points of contact to secure the door, and the lift paddle itself is closer to hand for the driver.

A better user experience would involve installing a button directly in front of the driver that can be easily accessed to actuate the door. This more advanced design would use a mechanical rotary latch or an electronic latch that hidden from view and connected to the button via a cable or through direct actuation.

To prevent the door from dropping open all the way and spilling the contents of the glove box, incorporating a friction hinge that allows the door to slowly open makes sense — and adds a strong impression of quality and sophisticated design that improves a user’s overall impression of the vehicle and its manufacturer.

Additional layers of safety and security can be included: certain electronic latches can be programmed to not open if the car is moving at a designated rate of speed or if the vehicle’s key fob isn’t inside the car. All of these features are possible. The challenge for the equipment manufacturer is to clearly define the total user experience and the complete impression of quality, refinement and functional ease they want to provide to vehicle owners.

Another factor to consider during the design process is that glove boxes may not be routinely accessed as frequently as center console units. Many drivers open and close the center console to retrieve or put away materials multiple times during their commute. Incorporating an access device that is simple to use and can be actuated without having to glance down at it while driving creates a seamless experience for the operator.

By the same token, the cover should pop open and stay open until the user is done, and not close due to bumps or vibration caused by the car while it is in motion. Latches and hinges that are designed to deliver ergonomic operation can be integrated during the manufacturing process to ensure that the driver never has to think twice about how easy it is to access the center console.

Enabling Repeatable User Experiences

No matter what type of equipment or devices manufacturers are providing — aircraft seating, automobile interiors, self-service kiosks, gaming machines, equipment enclosures for telecommunications or electrical equipment — providing the right access control and positioning control mechanisms are essential to delivering the easiest and most effective user experience.

The key is to determine the full usage case for each application: What ergonomic effort should be expended to open, position and close a device? What user feedback is needed or desired to accomplish this motion effectively and on a repeatable basis?

Repeatability is key — for both the individual device and for the system as a whole. Whether delivering large volumes of automobile interiors or equipment enclosures, it’s critical that the manufacturer designs and acquires access control and positioning devices engineered with the precision and quality to deliver years of smooth performance of the lifecycle of the equipment.

These small mechanisms can have an outsize impact. Leading mechanism suppliers have invested time and resources into providing the engineering and design support to help manufacturers achieve this result. They are ready to work with equipment manufacturers to custom-configure and cost-efficiently produce tens of thousands or hundreds of thousands of mechanisms depending on demand. Thus, mechanism suppliers and equipment manufacturers must work together to ensure that the right mechanism is delivered to maximize the quality and efficiency of each user experience.


Author: John Snyder, General Manager, Transportation, Southco, Inc.