Some examples of Matt’s previous work…
- Alsat-1B (Earth Observation satellite) @ SSTL
- GMP-T (Geostationary satellite) @ SSTL
- T6 Ion Engine measurements @ QinetiQ
Alsat-1B (Earth Observation satellite) @ SSTL
As a Lead Mechanical Engineer at Surrey Satellite Technology Ltd I was responsible for the mechanical design of both Earth Observation and Geostationary spacecraft.
My responsibilities included both detailed and top level mechanical design work. Both before I became a Lead Mech and during, I worked on the module boxes for power, avionics, data recording, and a whole host of other subsystems. Once I became a Lead Engineer I then had design authority for the full spacecraft at top level. My responsibilities included the layout of the spacecraft, the accommodation of payloads (optical telescopes, telecommunications hardware), and the design of the main structure – this consisted mainly of machined metallic components along with composite structures such as Carbon Fiber-Reinforced Polymer (CFRP) and aluminium honeycomb panels. As well as being able to survive harsh launch environments, it also provided the structure for integration of the solar panels and various other mechanisms necessary for normal spacecraft operation. In addition I looked after the various ground support and handling equipment, such as lifting frames, panel handling apparatus, etc. It was also my job to manage my own resources, both labour and materials, while of course keeping everything on schedule. Liaison with SSTL’s own customers was also a huge part of the role.
My latest project Alsat-1B was an Earth Observation satellite built on a proven heritage SSTL-100 platform. This spacecraft is approximately 100 kg in mass. The requirement for a brand new payload (and its extra associated equipment) was an interesting design challenge, as it had to be integrated into this standard spacecraft without compromising the design heritage. This particular payload consists of a 24m multispectral imager and a 12m panchromatic imager. The main purpose of this spacecraft is for use in agriculture, but like many others it will also form part of the Disaster Monitoring Constellation, which pools space imagery for the common good, providing data to the International Charter: Space and Major Disasters.
GMP-T (Geostationary satellite) @ SSTL
My first project as a Lead Mech at Surrey Satellite Technology Ltd was GMP-T. This was a development project to produce a SQM (Structural Qualification Model) – a qualified geostationary platform that will provide the basis for future projects. This spacecraft is physically much larger with its mass being in the order of several tonnes. The payload in this case related to telecommunications. The challenge with this spacecraft was producing a platform design that was generic, yet be sufficiently adaptable to accommodate a variety of unknown future payloads. Prior to this role, I began my career at SSTL as a design engineer, working on the new GMP-T power system development.
T6 Ion Engine measurements @ QinetiQ
My previous place of employment was at QinetiQ in the Space UK department. Working alongside experienced ex-RAE/DRA/DERA engineers, I learned key skills which I have continued to build upon until the present day. Mechanical design work and the associated drawings were a huge part of my role as a design engineer, however working at QinetiQ also gave me my first opportunities to solve difficult engineering problems, which again are skills I continue to enjoy using and building upon. During my time here I contributed to the main projects themselves; the UHF Transceiver for ExoMars (Mars rover mission), the T6 ion engine for BepiColombo (Mercury orbiter mission), and the Environmental Monitoring Unit (EMU) for Galileo (Earth global navigation satellite system). These projects all bought their own set of interesting challenges; however there were also very unique challenges to be found in the development of the ground support equipment.
For example, one particularly interesting task arose from the need to make sub-micron measurements of a particular component on the T6 ion engine. Due to the nature of the engine, with thrust being generated due to the ejection of ions, some parts experience an extremely small, but continuous degree of wear or “erosion”. This effect is one of the main limiting factors for the lifetime of the engine. While the effect is understood, the exact rate of wear had not been quantified. Life testing of the engines (continuous running) with inspections at specific milestones is routinely carried out. The requirement was to come up with a method to make accurate measurements of the parts in question at the inspection interval. Knowing that the change in component thickness was in the order of single microns (1 micron = 1/1000 mm), maybe even sub-micron, contact methods were unlikely to work (although they were experimented with). Surface imperfections/foreign matter also made contact methods unreliable. To make the task even harder still, the component had an extremely awkward form. After much research and development in conjunction with our colleagues from another site, we came up with the idea of focusing an X-ray beam onto a predetermined area, taking a cumulative count measurement (i.e. measuring how much X-ray radiation had passed through the component over a given time period), and comparing the result with a reference value. This process was repeated at a number of specific locations on the component. It was also necessary to make trigonometric corrections for most of the locations, due to the shape of the component. To provide a complete picture, the locations were also inspected using white light interferometry. This gave us an opportunity to physically inspect the areas in question by generating an image of the surface topography. This was also useful in that it indicated how certain features and/or foreign matter invisible to the naked eye may have affected the X-ray results.