Robogals Blog
Hear thoughts from active volunteers in the Robogals community.
Surely at some point, we've been fascinated by fingerprints and how they can be used to solve crimes. Human fingerprints are unique and are fairly consistent over time. Thanks to technological advancements, fingerprint pattern recognition systems are becoming automated and are increasingly used in applications such as identity management and access control [1].

Image taken from Fingerprinting Express.
Fingerprint Physiology
All humans are born with flow-like pattern of ridges and valleys on each finger. No two people have the same pattern – not even identical twins [2]. Light injuries on the finger surface only damage the pattern temporarily, and hence, the ridge will reappear when the injury heals [1].
![Image taken from [3]](https://dl.dropbox.com/u/14133270/0870210403003_level1.png)
Level 1 Features. Image taken from [3].
Fingerprint ridges can be categorised into three levels [4]:
- Level 1 features (Patterns) refer to macroscopic details such as ridge flow and pattern type. Generally, there are three basic pattern types: arches, loops, and whorls. These types are still insufficient in fingerprint identification.
- Level 2 features (Points) are the minutiae such as when ridges split into two, ridge endings, "eyes", and "hooks" etc. These features are sufficient in establishing the individuality of fingerprints.
- Level 3 features (Shape) include all dimensional attributes of the ridge and other permanent details such as line shape, creases, pores, breaks, and scars etc. These features are what forensic experts look for.
Level 2 and 3 features can provide quantitative and qualitative information in identification, which are useful in latent or partial fingerprint examinations [4].
![Level 3: Minutiae. Image taken from [3]](https://dl.dropbox.com/u/14133270/0870210403001.png)
Level 2 Features: Minutiae. Image taken from [3].
Fingerprint Sensing
Fingerprints can be sampled using the following methods [1]:
- The traditional "ink and paper" method involves applying ink to the finger surface, rolling the finger on a card, and scanning the card to generate a digital image.
- The manual "lifting" method usually refers to the dusting technique used to sample latent fingerprints during crime scene investigations.
- The automated "live-scan" method produces a digital image which is obtained by placing the finger on the surface of an electronic fingerprint reader/scanner.
For Automated Fingerprint Identification Systems (AFIS), there are two main types of "live-scan" sensors: optical and solid-state [1,5].
Optical sensors require the finger is to be placed on the top side of a glass prism (part of the sensor). Afterwards, one side of the prism is illuminated via a diffused light. The fingerprint valleys which have no contact with the glass platen reflect the light, whereas ridges that touch the platen absorb the light. This differential property of light reflection allows the ridges (which appear dark) to be discriminated from the valleys [4].
Solid-state sensors use silicon-based, direct contact sensors to convert the physical information of a fingerprint into electrical signals [4]. Differences in physical properties, such as capacitance and conductance of the ridges and valleys are detected by pressing or sweeping a finger against the solid-state sensor [1].
Fingerprint Matching
Automated fingerprint recognition systems usually have two stages of operation: enrollment phase and identification phase [1].
During the enrollment phase [1], the sensor scans the user's fingerprint and converts it into a digital image. A minutiae extractor processes the fingerprint image to identify minutia points that are unique for every user. The system saves the minutiae information, such as location and direction, along with the user's information in the enrollment database.
During the identification phase [1], the user touches the same sensor, generating a new fingerprint image called a query print. Minutiae matching is one of the most common approaches used in fingerprint-matching algorithms: minutia points are extracted from the query print, and the matcher module compares the extracted set with stored data in the enrollment database to find the number of common minutia points. Minutiae that have similar location and directions are deemed to be matched. The match score between two fingerprints should be high for the same finger and low for those from different fingers.
...
Things become more difficult and complicated when altered, fake, or severely damaged fingerprints [6] come to play, but this should hopefully get you interested in fingerprint matching.
This is a great example of how technology can aid identity management, forensics and law enforcement.
Cheers,
Sarah Li
References
- A. K. Jain, J. Feng, and K. Nandakumar, "Fingerprint Matching", IEEE Computer Society: Computer Magazine: February 2010, pp. 36-44, Feb. 2010. Web Link.
- A. K. Jain, S. Prabhakar, and S. Pankanti, "On the Similarity of Identical Twin Fingerprints", Pattern Recognition, vol. 35, no. 11, pp. 2653-2663, 2002.
- D. Braggins, "Fingerprint sensing and analysis", Sensor Review, vol. 21, no. 4, pp. 272-277, 2001.
- A. K. Jain, Y. Chen, and M. Demirkus, "Pores and Ridges: High-Resolution Fingerprint Matching Using Level 3 Features", IEEE Transactions on Pattern Analysis and Machine Intelligence, vol. 29, no. 1, pp. 15-27, Jan. 2007.
- T. Harris, "How Fingerprint Scanners Work", HowStuffWorks.com. Web Link.
- J. Feng, A. K. Jain, and A. Ross, "Fingerprint Alteration", MSU Technical Report, MSU-CSE-09-30, Dec. 2009.
Last Tuesday, Marita and I were at a lecture and dinner with Nobel physics laureate Professor Brian Schmidt, hosted by one of Robogals' sponsors, NICTA. Professor Schmidt was part of an international team who proved, contrary to what was previously thought, that the rate of expansion of the universe is currently expanding, which he explained to us in a very engaging presentation. At the dinner afterwards we were fortunate enough to meet Nina Hooper, a recent high school graduate who has just been accepted into Harvard University to further her dreams of becoming an astronaut! Marita interviews her in this short video about her goals and ambitions for the future.
This was the essay I wrote that awarded me with a scholarship to attend the ICWES15 Conference. The scholarship was given by the Victorian Division of Women in Engineering. The topic we had to discuss was "The best way to attract, develop and retain women engineers and scientists".
The topic of the best way to attract, develop and retain women engineers and scientists is a subject that is very close to my heart. I have done a lot of work in the area of women in engineering as the founder and director of Robogals, so I am aware of the issues that influence whether women pursue a career in engineering or not. I think the best way to attract more women to engineering is through outreach programs where female engineers can present themselves to schoolgirls as role models and do fun engineering activities with them to get girls inspired about engineering. On completion of their tertiary degrees, engineering companies need to engage with female engineering graduates and address any concerns they have about the industry. Once engineering companies deal with the concerns women have about the industry, developing and retaining female engineers is not a problem. This topic has an enormous impact on me as an engineer in the 21st century as I want to start my own robotics company in the next couple of years.
I am the founder and director of Robogals, which is committed to substantially increasing the number of young women pursuing engineering in their tertiary studies and careers. As well as teaching over 1200 girls LEGO robotics lessons last year to get them inspired about science, technology and engineering, our other activities include the Robogals Rural and Regional programme, which allows us to reach out to and inspire girls in rural and regional areas, as well as the Parents and Daughters Science Challenge, which will be launched in late July this year, and which gets girls and their parents from all over Australia to videotape and submit a science experiment online to win some great prizes. The activities Robogals undertakes around the world are designed for girls primarily aged 10 – 14, as girls in this age range are yet to choose their senior year subjects and hence still have the opportunity to easily go down the engineering study pathway. I think activities such as these are key influences in engaging girls in the possibility of studying engineering and I think more support for them will ensure that more women are attracted to studying engineering and science. Organisations like Robogals will ensure that more girls study engineering in the future.
Once girls have finished their tertiary engineering degrees, engineering companies must engage with women by dealing with the concerns women have about their industry. I think there are two primary concerns for women working in the engineering and science industries – the work/life balance of having a great career, but also having children, and the engineering culture not always being very favourable towards women.
On the first point of the work/life balance, I think this differs for women in academia and women in industry. For women in academia, I know that taking a few years off to have children will result in a lower number of papers and citations, which affects their ability to raise money for research as compared to their male counterparts. I do not have a solution to that. For women in industry, I think it’s just a matter of forward planning. I’ve thought of this issue a great deal as I plan to have a life in technology, but I also want to have a family. Sheryl Sandberg, the Chief Operating Officer at Facebook provided the inspiration behind my solution. I intend to work very hard on my career and company until I’m 29, and then I intend to take a few years off work to start a family, while still being involved in my company in a reduced capacity. That way, I will be able to create a family without compromising on my career and professional contributions to the world. In order to attract women and allay them about their concerns of a work/life balance, I think it’s very important to speak with them and be upfront about the issue from the beginning so they can come up with a plan to have it all, while establishing a great career for themselves in engineering. To retain and develop women engineers and scientists, I think it’s important for employers to recognise that women may want to take leaves of absence in order to go and begin families, and to factor that into the company’s training programmes. If engineering companies were more open about having the conversation about integrating family planning into career planning, retaining and developing women engineers will be a lot easier.
On the second point about the engineering culture not always being very favourable towards women, I think that this will change when we have more women engineers and scientists. As well as that, in the technology industry, I think that companies who have more females in the higher up positions at the company contribute greatly to creating a culture that is kind to females. So, I think the solution to this issue is to just create a bigger pipeline of more women getting involved in science, engineering and technology in the first place.
As I want to start my own robotics company, the subject of how to best attract, develop and retain women engineers and scientists will have a significant impact on me as an engineer in the 21st century. In order to make my company one where both females and males will work willingly, I intend to incorporate all my suggestions into the recruiting process of my company and ensure that women engineers who come to work for me will be encouraged to come up with a life and career plan to ensure they can have a family while also being a professional engineer. I have already begun developing the technology for my company and expect to launch in the next couple of years. It would be great fun to have other women engineers join me on the journey, so I hope more women step up to the challenge to be an engineer with me.
In conclusion, I think that if we focus our efforts on getting more females into engineering degrees in the first place through programs such as Robogals, then we will have a greater number of women engineers and scientists in general. Following that though, I think that companies need to understand women’s concerns and address them early on so that women can have the freedom to enjoy their engineering careers while also having the flexibility to choose to have a family.
From Tuesday 19 July to Friday 22 July, I attended the ICWES15 Conference on a scholarship from the Victorian Division of Women in Engineering. On Friday 22 July, I was lucky enough to be given the opportunity to launch the Robogals Science Challenge (a national competition for girls aged 5 - 18) in front of the entire delegation! I'm very grateful to the Victorian Division of Women in Engineering for giving me the opportunity to attend. These are the notes for the short speech I gave at a Women in Engineering dinner later in the year summarising my highlights and experiences of the Conference.
Arriving at the ICWES Conference in Adelaide on Tuesday, I made my way to the Gallery of South Australia. Never before in my life had I seen such big gathering of technical women representing such a diversity of cultures. It took me at least 2 days of the 3-day conference to get over that feeling of overwhelm!
What was really great was the number of scholarships that were given out to young women from all over the country. A Robogal (female university student who was to participate in our second Robogals Rural and Regional Weekend in Melbourne in August 2011) from Newcastle, who I had never met beforehand, was fortunate enough to also get a scholarship to the conference. Upon hearing that I was going as well, she contacted me and over the course of the conference, we became close friends. It’s little things like that that make conferences like these so special.
On Wednesday, I found Dame Professor Jocelyn Bell Burnell very inspiring. Jocelyn is an astrophysicist who is known for discovering the first four pulsars. Her groundbreaking work in this area led to a Nobel Prize for her supervisor, Hewish, even though it was Burnell's own initiative that revealed the presence of pulsars. She told a story where another woman said to her, “you have a husband, a son and a home to keep. Isn’t that enough?” But it wasn’t enough for her because she wanted to be intellectually challenged in her work. Her speaking about the challenges she faced as a women scientist made me appreciate that we live in a very different world now where it's more socially acceptable to even have women at work and contribute to the fields of science, engineering and technology.
On Thursday, the highlight for me was the CEO Circle, and the Gala Dinner. The CEO Circle was inspiring for me, as I enjoyed hearing top female executives from all over the country speak about their leadership challenges and lessons. I love the courage, confidence and self-belief all those women showed in order to rise through the ranks and make it to the top. The Gala dinner was a very festive affair with dancing, a fashion show and great food. I enjoyed seeing all these women scientists and engineers just have fun together.
One of the key people I connected with at the conference was the MC, Ms Bernie Hobbs, who is a popular panellist from the former ABC show "The New Inventors". She overheard me tell one of the CEOs after the CEO Circle about Robogals, and she said, "I think that's a great idea!" We then later bumped into eachother in the bathroom where she offered to help us out if she could. And so she became a judge in our inaugural Robogals Science Challenge! Not only is she a judge, but she was instrumental in encouraging Sally and Veena, also from the New Inventors, to come on board as judges, and in getting Dr Karl to tweet about the competition. All of which gave the competition a lot more credibility and added to our promotions.
ICWES15 was a very positive experience for me and I hope the friendships I formed there will last a very long time.
The train ride from Melbourne to Adelaide takes 10.5 hours. Our train ran a bit late though and took just over 11 hours instead! 8am - 6:40pm. (Adelaide time is 30 minutes behind Melbourne time). (I spent most of the time sleeping). The Overland was pretty fun. The majority of the clientele were the young at heart, the seats were big and comfy, and the cafe prices were extremely reasonable - like those you'll find at a country store! (Which is great! And meant we could pig out on scones as well as our normal lunch). :)
We were welcomed at the station by Sarah Cirillo, the outgoing Adelaide chapter President and also the on-the-ground SINE Organiser in Adelaide.
Not only will this SINE be the best SINE ever, but we also had the most luggage ever, with 3 boxes of training materials and goodies to give away, and a suitcase!
After leaving our things at the hostel, we went to Sushi Train, a block away, for dinner.
There are 4 Sushi Train franchises in Cairns where I'm from, so I know the franchise well and am a big fan! Unfortunately, there are no Sushi Train franchises in Melbourne, so I've been looking forward to the Adelaide Sushi Train for a while now!
It was nice to catch up with Sarah over dinner.
Then it was back to the hostel for some winding down emails and business, before bed.
I also found out about Codecademy tonight. For those who want to learn how to code, it has a nice and easy-to-follow introductory tutorial. If you do give it a go, please leave your feedback below as I'll be interested to hear your thoughts about it!
Cheers,
Marita
PS: I'll upload some photos and delete this post script tomorrow. Need some forty winks now...
Hello everyone!
My name is Marita and I'm the Founder and Executive director of Robogals.
I'm currently in my 5th year of mechatronics engineering and computer science at the University of Melbourne. It's a long degree, but it's very challenging and stimulating. :)
I'm posting because tomorrow is when I leave (by train!) for Adelaide to attend the Robogals SINE (national conference) AU/NZ 2011. It's the 5th SINE we've ever run, and I'm promised that it will be the best. :)
There'll be heaps of fun activities, free stuff and amazing female engineering students there, so I cannot wait!
To have a peek at what's in store, we have new t-shirts! They arrived on Monday - two days ago - after the Melbourne and Global chapters went to the Synchrotron for a site-visit, which is why some of us were able to model the shirts.
Front:

Back:

The winning design is by Jonathan Diolaso from New South Wales, who wins a free t-shirt and the joy of seeing his design on hundreds of people all over Australia, the UK and the USA.
As well as that, we have free swag from our fantastic sponsors GE, Leighton Holdings, and Google for our early RSVPs.
Anyway, there's heaps more to do until tomorrow, so I'll blog again when I'm on the train on my way to Adelaide :)
Cheers,
Marita
Don't you hate it when after a photo is taken, you discover that you've missed the perfect moment or it turns out blurry? Now there is a camera, made by the company Lytro, that let's you "shoot first, focus after".
Shutter lag is the delay between triggering the shutter and when the photograph is actually recorded. A shorter delay means you can take more pictures in a short amount of time. This is especially useful when capturing photos of objects or people in motion. According to the company's website and PC World, the Lytro camera has no shutter lag and lets you take pictures quickly.
What's more interesting about the camera is that it utilises light fields. A light field is the amount of light traveling in every direction through every point in space. The camera is able to capture and store the entire light field of a given scene due to advanced hardware sensors and software algorithms. You can read a brief explanation on how the camera works here.
And why is a light field camera cool? It allows me to stop worrying about blurred images and choose where I want to focus:

Feel free to experiment with photos in the Picture Gallery!
Sarah
Hello again,
It's the Mid-year Break and there are no university assessments (for now). Hooray!
Today, I'd like to share a music application that was shown in our Machine Learning course.
UJAM is an application that allows everyone - from novices to skilled musicians - to compose music. UJAM is able to learn and analyse a simple input melody (sung or played on an instrument) and generate options for accompaniments such as harmonies, bass line, and drum beats etc. The user is able to edit, save, and publish their newly created music. A neat explanation on how it works is given by Jon Stokes in the Wired Magazine:
"Before ujam’s AI can lay down accompaniment, it must figure out which notes the user is singing or playing. Once it recognizes them, the algorithm searches for chords to match the tune, using a mix of statistical techniques and hardwired musical rules. The stats are part of the software’s AI and can generate myriad chord progressions. The rules-based module then uses its knowledge of Western musical tropes to narrow the chord options to a single selection. ...
As ujam gathers more data on users’ preferences and musical tastes, programmers feed this info back into the system, improving its on-the-fly performance. In this respect at least, ujam is like a human: It gets better with practice."
Pretty cool, right? Go ahead and have a try.
Cheers,
Sarah
A prominent ancient Greek philosopher once philosophized that a person is ‘defined by the choices they make’. I guess this would be an appropriate way for me to introduce myself to the one reader that happened to stumble across this page (so, a spammer).
I would love to be the perfect little engineering role model, but the sad truth is that I am far from being the girl with the best grades, or the one with the charismatic dreams, or even type of person who always makes the correct choices. Luckily, the happy truth is that I truly and honestly love being an engineer despite the 'I-want-to-kill-my-coursework!' thoughts. And through this blog I hope to show you exactly what our ever-changing and cool world is like. They say that enthusiasm and fun is infectious; hopefully this rule holds through the interwebs too :)
As a plump child who pretended she had a spaceship and alien friends, I began forming a dream. I wanted to be an adventurer! An explorer who pioneered beyond the unknown and fought off bad guys. Slowly this goal would evolve beyond recognition (I mean, I’m a nuclear engineer right now), but you have to have a starting point.
But as I progressed through my Mechanical Engineering degree, it began to dawn on me that I could be more useful if I remained closer to Earth. All my readers will be familiar with ideas such as 'global warming' and 'fuel conservation' (yes, even that spammerbot). Reading articles in the press made me think about nuclear energy as our main energy source in the future. But our current nuclear power plants (in the UK) were old and mouldy and totally outdated (kind of like the cheese in my fridge). I wanted to be a part of the nuclear renaissance, designing cool technologies such as Generation IV reactors and Fusion power plants. It was around this time last year that I moved from Imperial College London to UC Berkeley.
So I guess that’s where I am now. I know I’m on my way to fulfilling my dream, even though I’m not fighting baddies (unless you call CO2 a villain?). But I certainly feel like I’m exploring new territory with groundbreaking technology. I’m only an insignificant miniscule in the nuclear power engineering world, but I like to think that my grad school work will eventually contribute in some convoluted way.
I guess the main point I wanted to get across this jumble of words is that: Don’t be scared to dream big. And don’t be scared if your goals and desires change along the way. In fact, I recommend having more than one dream. I mean, the worst that can happen is that you can't remember what answer you put down to your password security question 'What's your dream job?' As long as you are still passionate and driven about what you want to do, you will change the world. Even if it’s just one math problem at a time.
Hello!
This is my first post entry as a blogger for Robogals. Perhaps I should introduce myself. Here goes...
My name is Sarah. I've always liked maths and science in high school. That's my justification for choosing to study Engineering at university. Doing things you enjoy can't be that bad, right? Fast forward 3 years and here I am: a final year engineering student studying at the University of Queensland, Australia. No regrets!
I am majoring in Electrical and Biomedical Engineering - combining problem solving skills from electrical engineering with biomedical sciences to improve health care. Some university courses I have completed or am currently taking include:
- Human Anatomy - the study of form and structure of the human body;
- Systems Physiology - the study of major organ system functions of the human body;
- Signal and Image Processing - the analysis and application of signals and images;
- Image Formation - an introduction to medical imaging techniques such as Magnetic Resonance Imaging;
- Photonics - the science of harnessing light to create devices that comprise both electrical and optical functions, such as LASERs;
- Machine Learning - a branch of artificial intelligence concerned with the development and application of algorithms that allow computers to evolve behaviours based on example data or previous experience.
So back to this blog. Hmm... What should I post? I'm still a student and hence, there are many things I don't understand. So let's start with what we learn in university, brief updates on new technology, and science-fiction / cyberpunk awesomeness to enthuse the imagination.
You'll hear from me soon :)
Sarah
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