FYP2 : Week 13

Start writing Chapter 4

Objective : 

• To write project form the project

• To get the fall signal reading threshold from accelerometer

Activity: The main important part of this project is to get the fall accelerometer reading threshold to detect fall occur. This is to differentiate between fall with other routine activities such as walking upstairs, walking downstairs, sitting down and sitting up.. Accelerometer was attached on the wrist during the experiment.

Graph during walking upstairs

Graph during walking downstairs

Graph of sitting down

Graph of sitting up

Graph of falling

As the accellerometer have 3-axis which are X, Y and Z. The Y-axis represent vertical acceleration, X-axis is forward acceleration and Z-axis for side-away acceleration. The starting value for X and Y axis at 0 while for Y-axis at -256. Most of the activities did not give much different to the accelerometer reading except for sitting down and fall. Sitting down produced negative peak value of Y-axis meanwhile fall produced positive value of Y-axis which is 700. From all activities, Y-axis give the most differences value of changes during the activity so this project chose to only detect the Y-axis of accelerometer and set the threshold value at 700.

Conclusion : All routine activities produced different value of accelerometer output. The axis that produced the biggest changes among the three axis was Y-axis so noted that only value of teh Y-axis of accelerometer was covered in this project and the threshold for fall detection is 700 and above.