Abdullah-Zeerak Educational and Learning Group

Segway Project

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Base cutting with dimensions 14", 17", 4"

Posted by azelg2 on March 16, 2011 at 7:26 AM Comments comments (0)

Material Purchased for Base Structure

Posted by azelg2 on March 16, 2011 at 7:25 AM Comments comments (0)

Further research on the PT

Posted by azelg2 on December 13, 2010 at 7:20 AM Comments comments (0)

After submitting the FYP abstract and clearing up some confusions regarding the advisor and co-advisor, we sped up the hunt for ideas. We also began "market research" of those things which we will need to buy to in order to make the PT. Among the main things required are batteries, motors, microcontroller, gyroscopes, accelerometers etc. The inventory of the components required is as follows:

Batteries Around 500 Wh capacity, 24 or 48 V (depending on the motor). Lead-acid ones, even they have a poor energy/weight ratio, are the only ones we can afford. Cost : approx PKR 4000.

Motors To accelerate a 100 kg load to 10 m/s in 10 seconds with wheel diameter of 0.30 m, would require two 200W motors. The original segway uses 2 highly compact neodymium-magnet motors of 1,500W each, but they also cost thousands of dollars. We have to make do within few thousand Rs. So we will have to use slightly bulky and under-powered motors, but those which still do the job satisfactorily. Hence use of brushless DC motors is currently in planning. A pair will cost approx 5-10 thousand PKR.

Microcontroller We will be using the AVR ATMEGA32 microcontroller. It is quite powerful and will be more than enough for operating the PT. Cost (including board): PKR 600.

Gyroscopes and Accelerometers They will be used for tilt sensing. We have several options regarding this, including ones from Analog Devices and STMicroelectronics. Cost: approx Rs. 3000.

Idea Selection

Posted by azelg2 on October 10, 2010 at 7:14 AM Comments comments (0)

The path to the selection of this project was not straightforward. To decide one, we brainstormed several ideas and there was also some inter-group conflict regarding the FYP choice. But there was agreement on one thing: that the project should be a challenging one and never before been done at NUST. Thinking along those lines, we seriously considered these three ideas (in chronological order) before settling on the current one:
3. Segway

1. Directional microphone using phased array
This is a system of microphones placed in a pattern of 1, 2, or 3 - dimensional arrays (in linearly increasing order of performance and exponentially increasing order of complexity). We intended to make a system to enable listening to a distant source of sound while rejecting other noise in its periphery. However, after extensive online literature and commercial product surveys, we decided that the result (in terms of SNR) achievable within our capability and budget would not be enough to enable sufficient voice clarity at an acceptable range.

2. Electromagnetic coil gun After rejecting the mic array idea, we came up with another even more daring one: the electromagnetic coilgun. It is (not so closely) related to another, even more powerful system: the electromagnetic railgun. In those, electromagnetically propelled projectiles weighing 7 kg have reached speeds in excess of 3,000 m/s. By comparison, the most powerful sniper rifle's bullet speeds (weighing 0.05 kg) normally top out at around 1,500 m/s and normal handguns fire at ~500 m/s. Our minimum aim was a modest 100-200 m/s, still fast enough to seriously injure if it hit someone.
Before deciding on the project, we actually conducted practical feasibility experiments in the labs using 400V capacitors and motor winding coils. Though the tests were encouraging, upon further research, we calculated that to make a sufficiently powerful working gun, the costs of the required components (mostly the megajoule capacitors and 1000V/400A SCR's) would be too much for us, and so we had to abandon this idea as well.

3. Segway This idea was originally floated by Mr. Abdul Afram and was actually the first one we agreed upon. But before finalizing, we decided to explore the above-mentioned ideas.