INFO305

Beacon Testing This week we got our test app working and then began our first test of the estimote beacons. We wanted to test how different the x and y coordinates were on the android app in comparison to the actual positions. Method The phone was positioned 1.35 meters from the ground (the height of the beacons) using a tripod. We took measurements at meter intervals across the room, taking three measurements at each position. To take a measurement we opened our test app and waited for the reading to stabilise. We then closed and reopened the app in order to reset the app fully, to then take further measurements. The difference between the sensor and actual x and y positions were calculated for each testing position by subtracting the actual value from the test value. Frequency plots were made to gauge the accuracy and precision of the sensors to locate the mobile device in the x- and y-axes separately For the next analysis, we calculated the mean o...

Compass Testing As well as the Estimotes we were given the task of evaluating the accuracy and precision of the compass on a cell phone. The phone’s compass app uses a combination of two sensors, the magnetometer (a sensor that measures the earth’s magnetic fields), and the accelerometer (which can tell where the cell phone is pointing) to come up with a digital equivalent of a traditional compass. The magnetometer determines where North and South are based on how the sensor interacts with the Earth’s magnetic fields and then takes the direction of the compass to calibrate that information and give us a result. To test the accuracy and precision we first wanted to break down what is is to be “accurate” and what it is to be “precise”. Accuracy and precision may seem similar in a lot of way, but have two distinct meanings. We can say that something is accurate if it matches the ground truth; that is, it matches the desired outcome. For example, a dart thrower is accurate if they ...

Set Up Coming into our second week of working with the estimote beacons, we met up after the Monday lecture to discuss what we achieved in our first week and what our next steps are moving forward. Last week we all downloaded android studio to our laptops and forked from a central repository. Oliver then coded a small android application which downloaded and tracked information from the closest beacon. In our meeting we discussed a few variables that we could change in order to test for precision and accuracy of the sensors, including changing the distance of the beacons, the orientation (whether the beacon is flat on the surface or stuck onto the wall) and the surrounding environment of the room (including size and whether magnetism would affect the sensors). Tuesday’s meeting consisted of us tidying up the code to our application, enabling us to combine all the information from multiple beacons, not just the closest one. It also gave us a chance to talk to Tobi and realise we ...

Estimote Sensors This week marked the first week for our project, and consisted of finding a team and choosing a type of sensor to evaluate over the duration of the project. Upon forming our team, we decided upon the ‘Estimote Location Beacon’ ( https://estimote.com ) sensors to analyse over the course of our project. The aim of this project is to gather data from our sensor technology, then contextualize and portray the results in an informative way, by performing tests and analysing the results, we will be able to collect informative data on the accuracy and precision of the devices we are studying. All the readings are to be gathered by programming a small Android application. The devices themselves, are somewhat interesting in nature, they are intended to provide real time tracking information of a specific Bluetooth enabled device inside a room, using a form of Bluetooth tracking technology. The sensors must be attached to walls about chest height around the room, and after...