Design a waterproof connector piece (male and female) to easily interconnect carbonfibre rods/tubes of 1 meter (Ø 38/34 mm) by screwing them onto eachother. These rods contain sensors and electronics so the connector piece should be equipped with a connector to connect at least 3 wires between the rods. The connector pieces are currently glued inside the carbonfibre tubes but a locknut should be added too.
Multiple rods are screwed on each other to have a big rod of around 3 to 4 meter, which is being used in small waterways (rivers, creeks,...) and are pushed into the bottom to indicate soil characteristics. This means that connector piece should be as light as possible (currently in aluminium) to keep it manageable, but should be strong enough to avoid bending on the connector sections.