MechChem Africa January 2019

⎪ Automation, process control and instrumentation ⎪

Tectra Automation has designed and supplied a purpose-built assembly tower to integrate and align the lenses for a new space telescope for a low orbit satellite. Assembly tower integrates Simera’s space telescope

A new space telescope, for launch into low Earth orbit as part of an electro-optical payload for a satellite, was recently designed and assembled by Simera at its laboratory in Somerset West. To execute the ultra-precise specifications required for the Simera SX1 Imager’s optical calibration, the company contracted Tectra Automation to design and supply a purpose-built assembly tower to integrate and align the telescope lenses. Requiring a sturdy, highly stable design to mitigate the effects of external vibrations when installing and aligning the lenses, the tower structure was built using the Bosch Rexroth rangeof heavy-dutymodular alumin- iumprofiles andaccessories. Inside the tower, a vertically translating carriage mechanism was designed to assist with the alignment of optical elements. To achieve absolute control and smooth guidance of this mechanism, Tectra Automation used Bosch Rexroth ball rail

system linear guides with pneumatic brakes for maximum rigidity. Four counterbalance units fromBosch Rexroth, positioned at each of the four corners of the carriage, were used to maintain optimum positioning control for the 30-kilogram telescope at all times in the assemblyprocess.Thepneumaticbrakeswere controlledby anAventics panel whilst a linear scale with digital readout provided an accu- rate indication of the position of the carriage. The tower was then mounted on an ap- proximately 400 mm solid granite table suspended on vibration isolators to isolate the structure from any possible external vibrations, including those emanating from the nearby N2 highway. “The optical tower was a critical piece of laboratory equipment in ensuring a fully integrated, optically tested and flight ready solution,” explains Rosca deWaal, mechanical engineer for Simera. “Its design and construc- tion provided the highly accurate and smooth verticallytranslatingcarriageSimerarequired

Tectra Automation designed and supplied the assembly tower that integrates and aligns the telescope lenses for Simera’s SX1 Imager. to ensure optimum calibration of the tele- scope lenses.” The flight model of the telescope was successfully launched in July 2018 and, following from the successful delivery of the optical tower for the Simera telescope, Tectra Automation has received an order to assemble an additional tower for a smaller telescope. q

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