ASLI-2007

Pathfinder Airframe Complete/ End of Year Expo

2007-10-29T16:35:00.000+10:00

The Pathfinder 01 airframe was completed and shipped to South Australia on the 23rd of October for display at the end of year undergraduate expo's at both Adelaide & Flinders Universities. Displayed in the above picture minus the payload compartment is Pathfinder with Adelaide University (UoA) student team left to right: M. Pathmanathan S. Barone S.M. Wilksch A. Thomas

Above is the version 0.1 Recovery Controller (RC) developed by the UoA team, next to the Pathfinder rocket for scale. It is based on the powerful and flexible STR71 ARM MCU, which was chosen for its processing power along with the myriad of interfaces on chip. The unit provides barometric altitude in combination with a 3 axis accelerometer with +/- 50g x,y axis & 100g z axis. Interface to the main flight computer is via serial link, with the option of CAN and or USB. A PC104 form factor was chosen to allow ease of integration through a stackable board standard. Additional 18bit analog channels are available via pin headers onboard, which allow further vehicle discrete measurements.

The generous support of ST Microelectronics with development tools, and MCU's made possible the rapid development of a first generation hardware solution.

October ASLI Update

2007-10-12T10:35:00.001+10:00

Pathfinder Update:

The Pathfinder airframe is now at about 70% complete, the phenolic body tubes have been fully laminated using a seamless glass weave sock. Sourced from Aerosleeve.com in the U.S.

As can be seen below the fin unit is near complete and consist of a phenolic tube core, with 4 MDF diamond aerofoil cores. Over which has been applied a first layer of uni-directional carbon, a sencond layer of light glass bi-directional mat is to be applied.

The Pathfinder is currently undergoing final finishing and will be painted ready for display at the end of year expos for both Adelaide and Flinders Universities.

A revised launch plan has been drafted which will see a low fidelity launch on a commercial Hypertek hybrid motor, from a launch site in Queensland. The full briefing document for the launch will be available from this blog page by the first week of November.

Adelaide University Sub-controller Work

2007-09-27T11:38:00.000+10:00

The University of Adelaide Team has produced a prototype board based on the STR710. This was necessary to test tooling at the university and basic hardware concepts.

The PCB was manufactured at the University by the technical staff and loaded by a student team member. During testing some minor errors were noted. The PCB was modified and a fully functional circuit was yielded.

As the prototype has been tested successfully, the PC104 Recovery Controller can now be manufactured confidently knowing the basic hardware has been validated.
When the Recovery Controller is completed it will undergo initial testing with a PC, followed by integration to the central Flight Computer (FC).

The Linux based flight computer code is being developed, for use on the Arcom Vulcan XScale board. Integration and testing of a wireless telemetry using 900Mhz spread spectrum transmitters, will be conducted using Aerocomm data modems supplied by Tekdis.
To help speed implementation the team decided to use a PC104 carrier card from embedded arm to interface the Aerocomm modem directly to the Vulcan PC104 data bus.

Flinders University IMU update

2007-09-14T18:06:00.000+10:00

The Electronics for the payload unit being developed at Flinders University are now 90% built. The inertial sensor and GPS board is shown mounted on top of the PC104 single board computer. This configuration will form the payload module from Flinders University.

The build was mostly successful although a few complications occurred in the process. The gyros used are ADXRS300 parts which are only available in a 32 ball BGA part which is difficult to mount by hand without the necessary equipment. 2 of 3 were successfully placed on the first attempt using a hot air tool, the third was a failure. Another gyro is being sourced as a replacement.

The board is currently being tested and programmed to interface to the Vulcan single board computer. The single board computer is running an extended kalman filter under the eCos operating system to estimate the rockets position and attitude from the inertial data and GPS.

ASLI Rocket Team VaPak Propulsion Update

2007-07-21T17:35:00.000+10:00

A critical milestone in for the Pathfinder 01 development program was scheduled to take place July 24th, when the newly designed liquid propellant motor was to undergo qualification firings. However last minute logistical issues required that our team postpone the planned firing, pending a new safety review.

The term VaPak has been applied to propulsion systems that utilise the vapor pressure of one or more volatile propellants, to deliver said propellants to the rocket motor. Thus negating the need for separate high pressure feed or pump systems to deliver propellants to the rocket motor, leading to greater overall simplicity and reduced cost.

Our innovative design uses a high vapor pressure liquid oxidizer (Nitrous Oxide) and standard Methylated Spirits (95% Ethanol), to provide a simple, safe and efficient propulsion system. And is based on the proven heritage of Nitrous Oxide based hybrid rocket developments of the last 10 years.

Potential hazards associated with other forms of propulsion are largely eliminated due to the following.

1/ Nitrous Oxide is loaded remotely with operators more than 50 meters from loaded flight tank.

2/ There is no explosive or toxic agents used, and ignition is only possible via the introduction of oxygen gas and high voltage spark. This is again facilitated remotely from a safe distance.

3/ Nitrous Oxide is non-toxic except for slight narcotic effect (Laughing Gas), as to is Ethanol.

Above is the motor hardware showing the outer casing, injector, phenolic chamber liner and nozzle housing closure.

The team did complete critical testing of the Nitrous Oxide Fill & fire system and the static test stand assembly, and are ready for rescheduling of qualification trials.

Flinders University Team Update

2007-07-21T17:16:00.000+10:00

The Inertial Measurement Unit (IMU) being designed for the rocket consists of 3 single axis MEMS rate gyros, 2 dual axis accelerometers, 2 dual axis magnetic sensors and a GPS unit. The magnetometer and the GPS provide absolute heading and position reference to minimize accumulated error in the inertial measurements. The IMU has been designed together with a CAN bus expansion module on a PC104 form factor. The base board has two smaller boards connecting at right angles to provide inertial sensing in all 3 axis. This board will be mounted on top of a PC104 XScale based single board computer(SBC) interfacing via two high speed UARTs (one for CAN bus, one for IMU). The board design has been completed and all components have been source courtesy of RS Components.

The eCos real-time operating system has been ported to run on the Arcom Vulcan board sponsored to the project by RS Components. eCos is a deeply embedded operating system designed for applications requiring fast deterministic response time.

Currently a Kalman Filter implementation is being to developed to run on the SBC along with a roll control algorithm to drive the discontinuous reaction jets.

Project UNIVULCAN update

2007-07-09T21:49:00.000+10:00

Through out the holidays the Uni of Adelaide team has been working hard to get all the items ready for the static test rig.

The ST development board kindly donated by ST along with other tools has been excellent to work with. It has offered an easy medium to develop & test software. Also lessons learned from the board will give invaluable insight into the development of our own STR7 based microcontroller boards.

The test stand load cell and pressure transducer have had there circuitry developed and built. Each apparatus has had simple tests to verify there functionality, with excellent results.

The real time data capture and wireless control systems are being continually developed. Currently the real time graphing we wish to use through the test fire is almost complete. Next the graphical control will have it output linked to the microcontroller.

Our nitrous components have arrived.
The nitrous oxide solenoids draw 8amps. Because of this and also the need to have a mechanical interlock, a control box was made to take a signal as input from the microcontroller. The box then outputs the function to the appropriate relay via a transistor switching arrangement, to cycle 3 solenoids ( 1 for NOX fill/ 1 for NOX purge / 1 for O2 flood ). The solenoids have been connected to the control box and tested successfully. Completed box is shown above.

An ignition test was completed to test how much time is needed for the ignition spark to take effect and to cause burning on the nylon hose. This nylon hose will hold the fuel and we are relying on it to burn to open the lines and allow the fuels to mix to produce a burn. To test a small section of nylon hose was taped to the ignition wire, it as placed in an oxygen rich beaker. As you can see in the movie it took very little time for it to burn. The shorter the sparks time the better as it reduces the EMC on small sensitive devices such as microcontrollers.

The team at University of Adelaide thank RS Components, Coregas & STMicroelectronics for thier generous support, of the A.S.L.I 2007 program.

Airframe Parts Arrive

2007-06-26T20:50:00.000+10:00

Over the last few weeks the numerous components of the Pathfinder airframe have arrived, from both local and international suppliers. For the purposes of strength and weight efficiency the airframe is based on a convolute wound paper/phenolic core, with a seamless glass/ epoxy overwrap.

Shown in the above picture from left to right:
1: Paper/Phenolic Airframe Tube (bare) 2: Paper/Phenolic Coupler Tube 3/6" Fiberglass Nose Cone 4: Paper/ Phenolic Airframe Tube w E-Glass Sock.

HV Ignition sparker test

2007-06-21T20:40:00.000+10:00

Students at Adelaide University conduct a test of the HV spark system, which will be used in the rocket motor fill & fire system.

Rocket motor components

2007-06-20T18:36:00.000+10:00

We have over 70% of the hardware for our liquid propellant motor finished.

Parts shown from left to right: 1/ Head dome Nitrous Oxide tank 2/ Bottom dome/ injector plate 3/ Nozzle retainer/ aft boat tail

Parts shown from left to right: 1/ Head dome Nitrous Oxide tank 2/ Bottom dome/ injector plate 3/ Nozzle retainer/ aft boat tail

Close up of injector face showing press-fit pneumatic fittings used for propellant loading as per U/C valve concept.

We will be completing the motor for static testing & qualification on the 12th of July 2007, watch this space for video footage soon after.

ASLI welcomes LEAP Australia & Alibre to our list of supporters

2007-06-20T17:47:00.000+10:00

The ASLI team has secured a new sponsorship agreement with leading engineering/ CAD software reseller LEAP Australia, and software developers Alibre.

LEAP Australia under agreement from Alibre, will supply the ASLI program with its powerful and easy to use CAD/ mechanical modelling software Alibre Design Professional for life of the program. Allowing our team to rapidly design, create and share virtual prototypes before committing to hardware.

We extend our thanks to Nathan Dwyer of LEAP Australia and the developers of Alibre Design.

For further info visit

www.leapaust.com.au

New 3D Drafts

2007-06-17T21:09:00.001+10:00

Render of the Pathfinder 01 Airframe

Pathfinder 01 payload section takes shape

Welcome

2007-06-17T19:56:00.000+10:00

Welcome to the blog page for ASLI 2007 a multi-year effort to produce a nanospace launch capability, by bringing together leading academic institutions, rocketry experimentalist and industry supporters.

The corner stone of this year’s program is the development of the following systems:

1/ The Pathfinder 01 reusable sounding rocket - ASLI

2/ A new Nitrous Oxide/ Alcohol bi-propellant rocket motor - ASLI

3/ Rocket loading firing system – Adelaide University

4/ Rocket avionics including ARM/ Linux flight computer – Adelaide University

5/ INS, guidance processor & roll control thrusters – Flinders University

We have almost completed the rocket motor, and construction has commenced on the Pathfinder airframe.

Watch this space for updates, images, videos and progress post as we proceed toward our September 2007 launch date.