New-Tech Europe Magazine | Feb 2017

Sensors Special Edition

Using this circuit and techniques, an M30-diameter implementation can provide 12 Watts of output power. The effective power over distance is 7 mm (Z) distance for M30. In addition, the coupling is tolerant of misalignment up to 5 mm. For contactless data transmission, the data is sent separately through a signal converter to a 2.45-GHz transceiver and out to a near-field antenna (Figure 3). On the receive side, the process is reversed. The first variant is designed for sensor applications and supports up to eight PNP channels, unidirectionally from receiver to transmitter, with a switching frequency of 500 Hz (maximum). Development of higher data rates is on going, with a goal of supporting industrial Ethernet at 100 Mbits/s. The data connection happens upon physical connection, and is by necessity dynamic, occurring without user interaction. The range is short, up to a couple of millimeters, which is good for security and RF emissions purposes. The connector can accommodate up to eight digital PNP channels, with the current variant. To enhance reliability, the data link uses redundancy in the 2.4- GHz channel, has minimal far-field interference and the antenna design is symmetrical to allow for rotation (Figure 4). It’s also tolerant of misalignment, rotation and tilt. The full system efficiency, meaning the efficiency of the power and data link together, is ~ >75% (output power of receiver end/input power to the transmitter). Of course, this depends on the load, the distance and other factors, but it also includes the losses through the data link and PC-board assemblies. In rugged or dangerous environments, connectors are hermetically sealed to

is no longer a limiting factor (Figure 5.) Issues typically affecting connectivity in harsh environments, such as water, dust or vibrations, no longer impact the reliable delivery of power, data and signals. Contactless connectivity can replace complex and expensive harness constructions and slip rings, enabling connectivity where you could not connect before. The ability to integrate sensors within the robotic graspers or “fingertips” for force feedback to the system also enables “gentle touch” sensitivity for delicate items. Data to date shows that the total cost of ownership (TCO) using contactless connectors versus traditional solutions is positive within the first few months through increased efficiency, reduced downtime, maintenance savings and increased output. It may be the case that contactless connectivity will provide designers with an entirely new way of thinking about mechanically designed machines. References: Connector Design/Materials and Definition and Benefits of Contactless Connectivity For factory and industrial environments where dust, liquids, and gases combine with friction, power and robotic system wear and tear through multiple axii of rotation, designers need a new approach to connectivity. This new approach needs to be able to overcome these many environmental and operational challenges to secure, reliable, flexible, and robust connectivity - for both power and data. The solution lies in a new interconnection system, based Connector Reliability Robert S Mroczkowski

IP67, even if they are not connected with each other. Unleash the robots The challenge of integrating contactless data and power translates to relatively high cost, so the target applications are those where the capabilities of classic connectors have reached their limit in terms of mating cycles or environmental conditions, or where the application requires complex harness construction, and especially for new applications, such as connecting through walls and materials, or connections on the fly. One such application is robotic systems, which are being increasingly adapted to manufacturing and production processes that require greater complexity and precision. Given the rigors of the environment and the cost of downtime, maximizing reliability through dependable connectivity can pay dividends in the long term. In a typical robotic application, cables limit the range of motion and the constant movement and friction of the mechanical parts also creates wear and tear. Robots also need to move rotationally to perform complex tasks. Traditionally, rotation is enabled with rotating connectors, spring cables, or slip rings, the latter of which are mechanically connected to stationary rings via brushes. Cables are used to position these copper rings in close proximity to enable physical contact with the carbon or metal brushes. The brushes then transfer the electrical current to the ring, creating rotation. This constant friction creates wear and tear on the moving contacts, slip rings and brushes, which must be replaced frequently. This results in increased downtime and reduced productivity. With contactless connectors, the deterioration of moving components

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