USE Network launch I UAV Works VALAQ l Cable harnesses l USVs insight l Xponential 2020 update l MARIN AUV l Suter Industries TOA 288 l Vitirover l AI systems l Vtrus ABI

37 As a result of these concerns, certification ratings such as IP67 or IP68 are highly prized in cables by vehicle integrators. The digits following the ‘IP’ (Ingress or International Protection) refer to a guarantee of minimum levels of protection against wires, dust, metal edges and liquid. Various material options are available, and they can be divided into three categories – rubbers, plastics and fluoropolymers. Silicone remains one of the most popular rubber choices owing to its high flexibility and bend radius, temperature resistance (from -90 to +200 C), flame retardancy and abrasion resistance. Concerns over its propensity for harmful outgassing though have tempered its popularity in recent years. Polyethylene (PE) plastic lacks silicone’s temperature resistivity – anything beyond -65 or +80 C will be harmful to it. However, it has dielectric properties that make it highly desirable in coaxial RF cables and other high-speed transmission links, especially when foamed or air-gapped, which lowers its dielectric constant. These properties are vital to UAVs carrying heavy, multi-sensor gimbals for time-critical missions such as wildfire mapping, search & rescue, and so on. One of the newer materials rapidly gaining traction in meeting the different needs in unmanned vehicles is fluorinated ethylene propylene. Like PE, it can be foamed to give it ideal dielectric qualities in high-speed coaxial and data cables, and like silicone it withstands temperatures from -80 to +200 C. It also has high resistance to fire and a wide range of chemicals, provides workable durability and flexibility Cable harnesses | Focus Unmanned Systems Technology | June/July 2020 Careful selection of cable insulation is key to ensuring the long-term survivability of autonomous vehicles in a range of environments (Courtesy of Ulti-Mate)