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Mouser Electronics White Paper Power and Temperature Power is also a vital consideration for designers. The development of lightweight, high-capacity battery technologies has been important in expanding the autonomous robot market. Lithium-ion (Li-ion) battery capabilities have been adopted across a wide range of industries. Most AMRs will use Li-ion battery packs as their power source (Figure 2). Li-ion's high energy density makes it ideal for robots, providing useful working loads and high operational endurance. The key to optimizing the capabilities of high-capacity battery systems is to ensure the lowest possible losses during the transmission of power around the robot. To minimize power loss, connectors must be fitted with low-resistance contacts. Connectors that employ solid machined contacts are ideal in these conditions, as they combine high current ratings with superior mechanical reliability compared to stamped and formed designs. Gold plating ensures the best possible resistance to corrosion and durability when exposed to vibration. 1 Even a contact with low electrical resistance will convert some of the energy passing through it into heat. If the current is high enough, this can increase the temperature of the contact and its housing connector. Manufacturers provide temperature derating charts that show how temperatures will rise as more current passes through the contact. Temperature is an important factor when designing power connectors, especially in systems using Li-ion batteries. These batteries are sensitive to temperature changes, which can lead to fast, uncontrollable heating within the battery—a condition known as thermal runaway. To help manage this risk, designers incorporate accurate temperature sensing and well-designed battery management systems (BMSs). This adds to the performance requirements placed on the connectors within robotic systems. Figure 2: Lithium-ion industrial high current battery pack. (Source: Xiaoliangge/stock.adobe.com) Choosing Connectors for Industrial Robots Connector requirements within robots are complex. Designers need to minimize size and weight to ensure the robot's best possible performance. The ideal solution is a system that combines the signal and power capabilities into a single connector. This connector must also be robust enough to function in the demanding conditions found on the factory floor. Meeting this challenge, the Amphenol Positronic Scorpion is a revolutionary modular connector system that engineers can completely specify (Figure 3). Incorporating up to eight different contact sizes and designs, these machined contacts can be arranged to ensure the optimal separation of power and signal functions. The connector can even be built to include spacers that allow additional airflow, greatly assisting with the thermal challenges created by high current ratings. Figure 3: Positronic Scorpion Configurable Power/ Signal Connectors. (Source: Amphenol Positronic) Instead of being built from a range of discrete components, Scorpion system connectors are molded using a process called monolithic injection molding. This process uses a modular die within the injection molding machine to create a customized plastic housing manufactured as a single piece of plastic. With contacts installed, it is supplied as a single part number. The advantages of this one-piece housing go beyond the logistical simplicity of a dedicated part number. Unlike conventional modular connectors assembled from several components, Scorpion connectors' one-piece construction is mechanically strong, a highly desirable feature in harsh environments. Designed for use in aerospace and defense, where systems

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