Student Research Projects

Student Projects 2003

	*On-Board Computer*
		A Real-Time Embedded Java Virtual Machine is being developed by Heinrich Venter which is an implementation of an Earliest Deadline First (EDF) scheduler using the Real-Time Java spec. The implementation is a non pre-emptive message passing architecture based on the scheduler used on Sunsat.

	*Mass Memory*
		Damian Hawes is working on the design of a Satellite Mass Memory Unit (MMU) with LVDS input/output lines utilizing ATA interface to storage medium (i.e. hard disk). The most likely source of data for the MMU would be a high speed multi-spectrum imager which requires an estimated data capacity of over 10GB.

		Ian Horsburgh is looking into mass temporary data storage using Nand Flash technology.

	*Attitude Determination and Control*
		Research work is in progress on improved imagers with 2.5m resolution, which will lead to using Forward Motion Compensation that is a well-known technique for taking high quality images. Chris Mouton is currently working on Automatic Forward Motion Compensation (FMC) using rate feedback for micro satellites. High-resolution imagers will be controlled by this technique to ensure high quality stereo images.

		Corne van Daalen is currently busy with the investigation into 3-axes orientation and translation control for a satellite by means of reaction wheels and thrusters.

		The development of a control system that is capable of flying a Radio Controlled (RC) Helicopter without human interference is being done by Nicol Carstens. A number of similar projects have been completed successfully at other universities. The International Aerial Robotics Competition (IARC) is one of the big driving forces behind a lot of these projects, but the number of possible applications are endless.

		Robert Skinner is looking at developing a moon sensor for satellite application.

		Iain Peddle's project is to completely automate a remotely piloted, fixed wing aeroplane i.e. from takeoff to landing. This involves developing a sensor package that is capable of determining the orientation, position, velocity and accelerations of the vehicle and integrating it with an onboard control microprocessor. Major design considerations will be the cost and the weight of the sensor and control circuitry.

		Reimer Berner is working on the design and development of a 3-axis electromagnetic actuator for small satellites, making use of Control Moment Gyros.

		Francois Malan is researching, "Position and orientation measurement between two satellites flying in formation". Satellites flying in close formation (less that a kilometer separation) is a relatively new concept. He will look at affordable and simple methods of effectively measuring the relative position and orientation between two satellites flying in formation. The method pursued will most likely consist of visual tracking by means of a compact digital camera.

	*Spaceborne GPS*
		SGPS Receiver Development is aimed at developing a Spaceborne GPS (SGPS) Receiver that can be used on LEO satellites. The method used is adapting a terrestrial GPS receiver to work in a LEO environment. This will be achieved by modifying the firmware running on the receiver processor for use in space; this includes adding an orbit propagator to the software for position estimation, adapting the Doppler search algorithms and modifications for high-velocity signal dynamics etc. We are porting firmware (GPS Architect) to run on the Zarlink GP4020 chipset (ARM7TDMI core) and using the Sigtec Navigation Development Kit. This work is being done by Benjamin Nortier.

	*Image Compression*
		The main goal of this project is to develop compression system to compress satellite photographs prior to download. Eduard Kriegler is currently investigating Wavelet-based image compression schemes in addition to possible processors for implementation, which includes the LEON, Altera Excalibur and MIPS.

		Dolf van Niekerk is working on the design and implementation of a on-board satellite image compression for a hyper spectral camera. The data from the image will be broken down into three sub-bands (one for each colour) and then JPEG Compression (DCT Algorithm) will be performed on the monochrome data in each of the three data-paths, simultaneously. For this application an Oak Technology PM-36 High speed JPEG Codec IC together with a ARM host processor will be used. The compressed data will be passed into Mass Memory (see Damian Hawes’ Thesis). The three colour bands will be re-combined after download and decompression.

	*Aircraft Dynamics*
		Keith Browne's project covers the initial analysis of the Short-Term Stability and Control derivatives of a ASK-13 glider. The project's goal is to produce a mathematical model of the aircraft's dynamics that can be used to build a simulator suitable for pilot training. To accomplish this the glider (ASK-13 ) has to be equipped with sensors to measure the motion of the aircraft and the control surface deflections. Using the maximum likelihood method the stability and control derivatives will be estimated from data collected during flight.

	*Radar Systems*
		Warnich Rust is focussing on the "Feasibility of using combined firmware and software architectures for the implementation of radar signal processors", a project initiated by Reutech Radar Systems (Pty) Ltd.

	*Digital Audio Restoration*
		The aim of Ewald van der Westhuizen's thesis is to extract audio from old Edison phonograph cylinders, once belonging to legendary Afrikaans writer and poet, C.J. Langenhoven, via a non-destructing, contactless method. Currently he is using a modified laser pick-up of a CD-ROM drive to measure the depth modulation engraved on the cylinder surface by means of various scanning methods, and converting it to digitized audio. Digital speech enhancement is also being performed to enhance the quality of the data.