Team History
Background
When the first solar car was designed and built, in 1982, not much was thought of it. It was a novelty, it worked, and it travelled at an average speed of 23km/h for 20 days to cross Australia from Perth to Sydney. At the time, people said it would never be practical. Had it not been for the efforts of a small community willing to challenge convention, solar car racing may have been confined to the history books as a one line item. In the last 25 years, environmental conservation has become an increasingly more important issue. Recently, new discoveries of oil reserves have for the first time fallen behind demand. The public interest in solar cars has been piqued. No other engineering endeavour in the last 25 years can claim to have fundamentally altered the public perception of what is possible with renewable resources in the same way as solar racing. This achievement has been made possible by the tireless dedication of teams around the world. The UNSW Solar Racing Team has faced many technical, social and physical challenges as any team in the world. This is the story of the Sunswift project...
The Sunswift Project
The Sunswift project is a real-life, full-scale, student-led
engineering project at the University of New South Wales (UNSW). The project aims to deliver the most innovative,
exciting, challenging and socially relevant student led engineering project in Australia. The UNSW Solar Racing
Team (UNSW SRT) is made up of undergraduate and postgraduate students who volunteer their time to design, build,
fund, manage, and race a state of the art solar car.
The project started in 1995, with the aim of providing engineering students with the skills and experience to become excellent professional engineers. In the past 14 years the project has had four main focuses: (i) Develop Innovative Technologies, (ii) Provide Practical Education for Students, (iii) Increase Public Awareness of Sustainability Technologies and (iv) Promote a Healthy Work Ethic.
The project’s claim for excellence is based on the knowledge that
the UNSW Solar Racing Team is the only solar racing team to have successfully mastered all of these areas of solar
car development. The team has developed student skills and experience, set world records and inspired a nation.
The UNSW Solar Racing Team is focused on providing an opportunity
for students work on cutting edge research. The Sunswift project continues to redefine the boundaries of what is
possible and push the development of what is required for the future. The very essence of solar car racing is
merging of disparate technologies to produce an integrated vehicle. Students learn how to bring designs to be
accessible to the public. Implementation of the technology used in solar cars is based on the necessity and
relevance of future land transport. The underpinning principle is to develop energy efficient design. Students
become proficient at design in the context of developing futuristic ideas and designs that have practical
implementation.
The majority of the engineering industry is limited to providing financially focused solutions, which are needed to supply day to day needs of society. To meet the challenges of the 21st century, engineers need to challenge current day convention. Technically, many of these solutions exist, however little progress has been made with regard to attitude change in the broader community. Arguably the Sunswift projects greatest engineering achievement is that over the past 14 twelve years the it has touched the lives of tens of thousands of Australians. The Sunswift project continues to be a practical demonstration of branching emerging research and development with end user orientated solutions.
In The Beginning
In 1995 a final year student electrical engineering student, Byron
Kennedy, was looking for a relevant and informative thesis project. Byron led what became the first student led
engineering project at UNSW. The team acquired a defunct solar car from a rival team, and began improving it. The
car Sunswift (formally Q1) was raced in the 1996 World Solar Challenge (Darwin to Adeliade), against teams such as
Honda and Biel, and finished in a very respectable ninth place. Byron Kennedy, now the Research and Development
director at FASCO Asia Pacific states that:
The lessons learnt and experience gained whilst being involved with Sunswift have directly contributed to where I am today. After completing the 1996 World Solar Challenge I worked at the Northern Territory University (now Charles Darwin University) researching further applications for axial flux motors (used in 90% of solar cars worldwide). In 2001 I was part of a team who setup the first spin off company from Charles Darwin University, In Motion Technologies, to commercialise the motor technology. We successfully raised funds and worked with a number of multinational companies before being acquired by Australia's largest motor manufacturer, Fasco Australia. Fasco is a subsidiary of the Tecumseh Products Company with sales of over $1billion worldwide. My present role is as the R&D Director of Fasco Asia Pacific working to commercialise motor technology originally developed for solar car motors in residential and commercial applications.
Having improved the vehicle to its technical limit the UNSW SRT were
keen to design and build their own car, UNSW Sunswift II. Extensive research and development was conducted into the
technologies available for use in the car. Over a period of 7 years, hundreds of students had the opportunity to
work on a cutting edge research and development engineering project, decades in advance of a practical
implementation of the technology.
The quality of work is evident in the technology produced in this
era of the project. There were four distinct refinements of UNSW Sunswift II built, each version incorporating new
developments, including electrical systems, solar cells and carbon fibre wheels, often as world firsts.
In 2004, the team took what they'd learned from the development of Sunswift II and designed a third car, Sunswift III, which was more efficient than it's predecessor, and had room for a passenger. After three successful events, and thousands of kilometres on the road, the team is innovating yet again, with the latest car... Sunswift IV. Designed to be more practical, with a steering wheel and an up-right seating position, the design looks to bring solar cars one step closer to reality.
The TopCell Project - Awarded the 2002 SunRace Enterprise Award for Technical Innovation
In 2000-2001, the UNSW SRT embarked on the TopCell project -- an
ambitious plan to manufacture 4,000 solar cells for a new array. The manufacture of solar cells was (and still is)
a world first for any solar car team. In addition, the UNSW SRT developed a new method of encapsulation that
allowed the team to construct solar panels with composite curves – another world first.
The TopCell project was established for several reasons – it
provided an unprecedented opportunity for hands-on experience to photovoltaics engineering students at UNSW. The
students learnt about the manufacturing process and engineering research techniques. 26 students relinquished their
summer break in 2000-01 to manufacture 7,000 high efficiency Buried Contact Solar Cells (BCSC), at 19.5%
efficiency. The entire project was completed in under 4 months and involved approximately 10,000 work-hours
The students managed the project themselves with the guidance from academics and laboratory staff. This required operating the laboratories, maintaining the equipment, fabricating the cells at all stages, testing the cells and solving the engineering problems associated with process control and process optimisation. The result was world record efficiency cells, manufactured by students. Due to this project, the team would have a more efficient array than was commercially available for the same cost. Ultimately the greatest engineering challenge was simply that the project had never been achieved anywhere else.
According to Jamie Green (Student Leader of the TopCell project), the project was an exciting education. “It has given the team a ‘real world’ chance to become experienced with semiconductor and solar cell technology, and an unsurpassed engineering opportunity,” said Jamie. “I feel that we have been given a head-start in the industry because of the unique skill level and experience that we all now possess.
“It’s really amazing what keen students can accomplish given the opportunity,” said Dr Jeff Cotter, one of the project’s academic supervisors …. “The TopCell students started the project with no skills or knowledge in photovoltaics and ended up with over 8 square metres of high-efficiency solar cells — and they overcame some pretty difficult problems along the way!”
Aside from the challenges in the lab, and the sheer quantity of
cells manufactured and fabricated into modules, there were several other interesting problems that arose while
making the array. The largest of which was the monumental challenge of encapsulating the cells into the curved
shape of the array. Once the encapsulation material had been chosen, the entire mould of the car needed to be put
under vacuum. Unfortunately, the 9m2 mould was not strong enough to withstand the vacuum pressure without
distorting. The only solution within time and budget was for the students to manufacture a custom vacuum chamber,
to support the mould as well as keep it under vacuum. Over a period of three months, the students designed and
constructed a 4 tonne steel mould, and finished making the array.
The outcome of a year's work were two world firsts -- an entire
array made by students, and the first time solar cells had been manufactured in curved panels. The students
involved gained valuable experience into a real life engineering process, including the difficulty of implementing
plans, and engineering solutions to the problems that arise. Many of the students involved in the project are now
working in solar cell research across the world.
The CAN electrical system – Awarded the 2002/2003 Siemens Prize for Innovation NSW division
UNSW Sunswift II saw one of the first implementations of a
Controller Area Network (CAN) within the solar car. The network monitors and controls the electrical system of the
car, from the high voltage battery pack and array, to the low voltage lights and horn, as well as the telemetry
network, which sends vital information about the car to the support vehicles.
While CAN systems have been used previously in solar cars, none have been implemented with as much success as in UNSW Sunswift II. The excellence of the CAN system lies with it’s reliability, simplicity, and ease of use. The network resulted from a realisation that the then-current electrical system was a highly specialised and centralised, and that these qualities led to its being unreliable and un-maintainable.
Prior to the development of the CAN system, a slight modification of
the electrical system would more than likely have resulted in an entire redesign. The wiring was complicated, and
the system was centralised, allowing only one user to see the data. The development and implementation of the CAN
has resulted in several major benefits.
The CAN system’s greatest strength is that it is decentralised. This
allows more than one user (the driver, the strategist, etc) to see the data generated by the various components of
the car, such as battery power, array power, speed etc. In addition to data readability, control functions, such as
speed control, indicators, brake lights etc, can be controlled over the network. The driver can now see the
critical data for the car, as can the support vehicles. Previously only one of the support vehicles could access
the data, and if the telemetry link between the solar car and the support vehicle car failed, the data would be
hidden and lost. A decentralised system also means that if one component in the system fails, the rest of the
system can continue to operate. The flexibility of a decentralised system allows for results in significantly less
down time for the electrical system and improved safety for the driver.
A decentralised protocol also means that if one component in the
system fails, the rest of the system can continue to operate, which was not the case prior to the development of the
CAN system. The flexibility a decentralised system allows for results in significantly less down time for the
electrical system and improved safety for the driver.
The technologies and ideas used in the CAN system, if not a modified
version of the CAN system, are easily transferable to modern motor vehicles.
The ’plug and play’ simplicity of the CAN system has opened the way
for many other electrical projects in the team. This has improved the development capability within the electrical
team as projects are able to be worked on in more depth than previously. This has allowed the team to introduce
many new monitoring systems to the car, such as tyre pressure sensors, to warn about upcoming flat tyres, a tilt
sensor to measure the angle of the car to the road as well as complex algorithms to optimise across various
predefined parameters, a GPS for position sensing, suspension position sensors, and other improvements.
In conjunction with the implementation of the CAN system, the power
electronics section of the car was modified. The result of the changes is that power generated at the solar cells
is utilised in the car at an efficiency of over 95%. That is, the losses in the electrical system were reduced to
less than 5%.
The UNSW Solar Racing Team has effectively set the benchmark for electrical systems for solar cars worldwide. The majority of solar car teams now run electrical systems based on the pioneering work of UNSW Sunswift II, and this is just one of the technologies that the UNSW Solar Racing Team has developed.
Commercial Technologies
The UNSW Solar Racing Team has, over the years, developed several
technologies which rival commercially available technologies.
Motor Controller
The motor controller controls current to and from, and hence the power used by the wheel motor, which powers the car. It is one of the most important, and irreplaceable parts of the solar car. The efficiency of the motor is a major component. The UNSW Solar Racing Team’s current motor controller is made by Tritium, suppliers of one of the world’s most advanced motor controllers.
The UNSW SRT was Tritium's first customer, and has enjoyed a close
relationship with this Australian startup. The team tested Tritium's first motor controller in 2001, and thoroughly
tested and ruggedised the device in 2002/2003. In 2004, one of the students on the team modified the motor
controller improving the controlling software and improving the efficiency of the drive train. The results of this
thesis were used to help guide the subsequent development of Tritium’s new WaveSculptor motor controller.
Carbon Fibre Wheels
The UNSW Solar Racing Team has had a long standing sponsorship from Boeing Hawker de Havilland, Bankstown. For the past 8 years, Boeing have been a technical partner of the team, and have provided material, facilities, and expertise with carbon fibre for the team. This partnership has given students an excellent opportunity to work with and learn about carbon fibre composite structures.
The longest standing design are the carbon fibre wheels on the
solar car. They have survived eight years, and tens of thousands of kilometres. The UNSW Solar Racing Team is not
the only team to use carbon fibre wheels, but they are the only team to design and make their own.
