Erich Reichenbach of Reichenbach International Inc. offers tips on how to specify connectors for drones, which require versatile, lightweight, and reliable components that perform in demanding environments.
Connectors for drone applications must be small, lightweight, rugged, reliable, and versatile, as they are exposed to a variety of demanding environments. Here are some factors to consider when specifying DRONE connectors:
Size, Weight, and Shape
If its fuel is conserved, a drone can fly longer or farther. Thus, to save fuel and weight, it is very important to use tiny lightweight connectors, about 0.1 ounce in weight and about 0.3 inches in diameter.
To follow signals from its distant operator or turn on/off reconnaissance devices, the drone will also need about four machined (and therefore highly reliable) contacts that will carry 3A each.
Circular connectors are preferable because they can fit in small spaces more easily.
Material, Shielding, and IP67
A small, lightweight brass-shelled connector is ideal for drone applications since it is rugged and resists salt water and various chemicals. As a metal, the brass shell also offers EMI/RFI shielding, which can be further enhanced with a small, lightweight 30AWG shielded cable.
Via a PEEK insert, a connector can be rated at -40°C to + 200°C, and can be terminated to a rugged Teflon-jacketed cable. Or alternately, a highly flexible HFS (flame-retardant and zero-halogen) 2A, 30AWG cable rated at -40°C to + 100°C can be used.
One connector on the market, via two internal Viton O-rings, offers both an IP67 water-resistant front and back. These features make it a very versatile connector.
A hex-shaped knurl can be used to thread the connectors together, which allows for three options when securing the tiny connectors so they do not become unmated during high-vibration scenarios.
Pictured from bottom to top are the following methods:
Wire holes in the ridges of the straight cable plug – The customer is able to put a wire through these holes and secure the wire to his unit or panel.
Wire holes with a quick-locking system – The customer can insert a supplied spring wire through the wire holes. The spring wire jams against the threads and keeps the connectors from unmating. The end of the spring wire can be bent to keep it from coming out of the wire holes. The other end of the spring wire is wrapped around the cable so that the spring wire does not get lost and can be reused many times. (A bulkhead receptacle is pictured, but any receptacle in the series will do.)
A silicone O-ring is included with the mating receptacle – The least expensive method, the O-ring acts as a washer when the connectors are mated and its resistance keeps the tiny mated connectors from unmating. This is an ideal solution, recommended for situations with minimal vibration. (An in-line cable receptacle is pictured, but a variety of receptacles will work.)
In the past, these specifications have required several connectors. Today, one connector can offer all these features.
Erich Reichenbach is the founder of Reichenbach International Inc.