Accelerometer Data

After a lot of toil and time (or not), I finally got my data from the accelerometers, and it does nt look bad at all! (Maybe good even!). I can now proceed towards analysis and make a scheme out of these. But there is a catch that I see in the preliminary results, I may need a better ADC and a much much better processor than the itty bitty ATMega168 on an Arduino board that I m using currently.

I need to write a report and submit it within this week about my results. Results are pretty much as I expected, I learned that I definitely need to filter my signals, which means computational power, (Kalman Filter maybe?) and that I can give a good estimation of tilt with the current sensors. I have nt been able to see forces, and partly because of the ADC. Forces are very very short in duration and I need a faster sampling to get some good data. Maybe 10, 20 times better sampling rate would give me better results. This would mean new components and new components would in turn mean a learning curve. I m swamped with assignments so I ll be putting this off for a little later, or maybe just slow down my pace so I can compensate.

Of Gyroscopes And Accelerometers

These days I have nothing much to do about my project, since I have ordered parts and waiting for them to arrive. I have always hated waiting, I m an impatient and impulsive person tending to have more than one obsessive compulsive disorders. But thats not what the post is about, so my current objective is to make a remote unit which can be used to determine the relative position of the user.

Now relative position may mean a lot of things and therefore in this context it means the current position with respect to the previous position. Now what I have decided is to do this use inertial sensors.

What are inertial sensors? They are sensors used to measure the change in inertia applied to the sensor, in lay man’s terms, if you apply a force and the object STARTS or stops to move, these sensors would give a corresponding voltage value. Now this is also not for the complete lay man (Read ouff) but I dont know any way simpler to explain this.

Ok, anyone who’s worked on this stuff would say big deal, This is old old technology and people have been using IMU (inertial Measurement Units) and INS (Inertial Navigation Systems) for a while now so whats new here. Well to tell the truth, nothing is really new here… Hell some people have also used this for smaller applications too like for determining orientation of an object. So there is nothing new to this… So why am I doing this and why the heck am I writing about it? Well I m thinking up a way to do this just by employing accelerometers! I bet this can be done, I m still working out the theoretical details. Now why would I use only accelerometers and not Gyros.

For that let me first explain what are Gyros and What are accelerometers. So the latter first, accelerometers are devices used to calculate translational acceleration, translational means moving from one point to another in a straight line. Now Gyros are more fun, they are used to measure rotational velocities, Now using the two together is usually the method used by everyone. But Gyros are expensive and difficult to get measurements from, plus you need to implement more household circuitry to maintain an output from them. While accelerometer are much more easier to do. So my motivation is simple. To make it easier for myself. But the more I come to think about it the more discouraged I get about this idea. Cuz the maths involved is way out there.

People, Any bright ideas? Please help!!!

Skittles and Me

I m pretty baffled by the size and scale of my project… And the quantity of expectations that my supervisor has of me and thus the proportional work required of me. He probably think I m some unsung under dog wiz kid outta Karachi who is just about to spread his glorious wings and stun the world. In the words of the Great Danny Crane, He wants me to pull a rabbit outta my hat (or ass, cuz I dont really have a hat).

I was lately studying Multi touch screens, I did a post somewhere here. Dont expect me to make it any easy for you and hyperlink that link here, GET IT YOURSELF!!!!. Now I m working on incorporating Gyroscopes and Accelerometers to give a more engrossing feel to the user carrying this remote unit which would be used in the project. Which is supposed to be somewhat familiar territory

Now previously, before the advent of the acclaimed iPhone, accelerometers (and Gyros) were some obscure sensors which only military used. Hell no body probably did nt even know their name and what they were used for.

So Currently I m making a design and a scheme which is used to to give a relative position (from the previous position) of a remote unit which you can currently think of as a 3-dimensional mouse. The idea I have right now is the combined effort (brain storming) of me with a german dude name Micheal Leigsnering (sorry dude if I mispelled your name). Since the idea is nt mature yet, I ll just keep it to myself and work on it, so that I dont give you guys any reason to call me nerd or geek or stupid.

So why am I writing this post??? Cuz I m on an overdose of sugar (read skittles) and my brain is on overdrive. I m at my lab sitting by my workstation with a bag of skittles. I have a habit of keeping a bag of skittles on me while I m working and write down some of my thoughts and ideas so that I can keep them in perspective and make references. So this post is kinda my reference point at the moment.