The objectives of the project are to assess and select manufacturing and joining technologies novel to R.F. passive space components in order to reduce mass, manufacturing, and Assembly Integration and Test (AIT) complexity.
The project aims include building demonstrators employing the selected technologies to quantify the improvements with respect to the current state of the art.
The key challenge is to develop lightweight, compact alternatives to the ubiquitous bolted flange found in R.F. components.
Apart from reduced mass (and volume), the proposed joining technologies will need to achieve R.F. performance comparable to a bolted flange, together with sufficient strength to survive launch vibration.
Achieving the R.F. performance presents its own challenges: the inside conducting surfaces are typically silver plated and need to be in excellent electrical contact across the inside surfaces of the join. Inspection or repair to the completed join inevitably becomes very difficult.
The numerous bolted flanges found in typical satellite R.F. systems can have a significant mass associated with them. The technologies investigated in this project have the potential to significantly reduce that mass penalty, as well as offering a more compact solution.
Following an extensive survey of potential manufacturing and joining technologies, including those already used in adjacent industries, laser welding and adhesives have been identified as the most promising technologies to study further.
Working with The Welding Institute (TWI), numerous trials have been undertaken to optimise the weld parameters associated with forming a good electrically conductive join on the inside surface of the join in the presence of silver plating. The work has identified the technology’s potential as well as identifying where further research is required.
Two adhesively joined demonstrator types have also been produced: a simple sleeved butt joint and a choked flange variant – see figures below.
The challenge with the sleeved joint has been to design and assemble a configuration that prevents the adhesive seeping into the critical waveguide butt join. The alternative coked configuration is an attempt to minimise the potential impact of adhesive migration by replacing the critical butt joint with an R.F. choke.
The aim of the project is to build demonstrators and subject them to environmental and R.F. tests before evaluating the potential benefit across a typical satellite system.
The specified phases of the project involve identification of potential manufacturing and joining technologies followed by down-selection against the requirements of a typical R.F. joint. Following manufacturing trials on the selected technologies, the requirement is to build and test demonstrators before quantifying the potential benefits in a satellite system.
The project has now completed manufacturing trials of the proposed laser welding and adhesively technologies and all testing activities have been completed successfully.