On November 11, 2026 in All, Connectors, Industrial, Robotics, Wireless by David Pike

Many connectors never have to accommodate movement. They are installed once, connected, and left in place for the life of the equipment. Power distribution networks, communications infrastructure, and most fixed installations follow this model. Even where some flexibility is required, it is usually limited. A charging cable or patch lead may be plugged and unplugged regularly, but it is not expected to operate continuously while in motion.

The situation changes when a connector must operate as part of a moving system. In industrial machinery, motion is often constant. Robots articulate through repeated cycles, inspection systems rotate components for analysis, and mechanical assemblies are designed to spin, index, or oscillate as part of their operation.

This blog explores how contactless connectors address the challenge of transferring power and data across continuously moving interfaces. It also compares contactless connectors with flexible cables and slip rings and examines their advantages and limitations in dynamic industrial systems.

Delivering Power and Data Through Moving Interfaces

Conventional cables are not always well-suited for continuous dynamic applications, particularly where repeated rotation introduces sustained torsional stress. While flexible cables can tolerate some movement, repeated rotation introduces a different type of stress. The cable bundle twists, and over time this twisting (i.e., torsion) leads to fatigue in both the conductors and the insulation. Eventually, a failure occurs, either gradually or as a sudden break. In either case, cable fatigue creates a maintenance problem. Cable routing can be carefully controlled to minimize the effects of dynamic operations. Cable chains or slip loops can help limit torsion and reduce cable wear, but they add mechanical complexity.

Slip rings were developed to solve the problem of connecting across constantly rotating joints. A slip ring allows electrical power and data signals to pass between stationary and rotating parts using a set of conductive rings and sliding contacts. Instead of twisting a cable, the connection is maintained through a rotating interface. Slip rings have been used for decades in applications ranging from radar systems to wind turbines, and modern designs can support high-speed communication.

A slip ring’s interface relies on physical contact between brushes and rings, so some degree of wear is inevitable. Over time, the contact surfaces degrade and require maintenance or replacement. In some applications, electrical noise generated by the sliding contact can also be a concern, particularly when low-level signals or high-speed data are involved.

Maintaining signal integrity across a slip ring is possible, but it often requires a more specialized design, such as shielding, dedicated signal paths, or hybrid approaches that combine different transmission methods. As a result, the solution can be more complex and more expensive than it initially appears.

Existing wireless protocols already deliver information without physical contact. Technologies such as Wi-Fi^® and Bluetooth^® can transmit data without a physical link and are widely used across many applications. In some cases, they can work well in industrial environments. However, these technologies have limitations. Industrial environments are often electrically noisy, with motors, switching equipment, and high currents contributing to a challenging electromagnetic environment. Maintaining a reliable wireless link under these conditions can be challenging. Latency and security can also be concerns, especially in critical control systems. In addition, while wireless connectivity can solve the data problem, it does not address power delivery needs.

Contactless connectors operate across a very short, controlled gap between the two mating halves. Rather than broadcasting signals over a wide area, power and data are transferred across a small, defined space between two aligned components. This approach avoids many of the issues associated with conventional wireless systems and eliminates the need for physical contact.

Continue reading the article at Mouser