Table 1.

State-of-the-art on smart cushions based on pressure sensor arrays.

Author	Sensor Array Type	Placement of the Sensors	Detected Postures	Classification Technique/Method	Accuracy
Xu et al. [26]	E-textile	cushion on the seat	Sit up, forward, backward, lean left/right, right foot over left, left over right	Gray scale image	85.9%
Tekscan [27]	E-textile	cushion on the seat and backrest	N/A	Pressure mapping	N/A
Tan et al. [28]	E-textile	cushion on the seat and backrest	N/A	PCA, Grayscale image	96%
Mota et al. [29]	E-textile	cushion on the seat and backrest	Lean forward/back, lean forward right/left, sit upright/on the edge, etc.	Neural Network	87.6%
Meyer et al. [30]	textile pressure sensor	cushion on the seat	Seat upright, lean right, left, forward, back, left leg crossed over right etc.	Naive Bayes	82%
Multu et al. [31]	pressure sensor on the seat and backrest	19 pressure sensors	Left leg crossed, right leg crossed lean left, lean back, lean forward etc.	Logistic Regression	87%
Kamiya et al. [32]	$8\times 8$ sensor array	cushion on the seat	Normal, lean forward, lean backward, lean right, right leg crossed, lean right with right leg crossed etc.	SVM	98.9%
Xu et al. [33]	Seat $6\times 8$, backrest $2\times 8$	Cushion on the seat and backrest	Lean left front, lean front, lean right front, lean left, seat upright, lean right etc.	Binary pressure distribution, Naive Bayes	82.3%
Fard et al. [34]	$8\times 8$ sensor array	cushion on the seat	Sitting straight with bent keens, crossed legs left to right and right to left, stretched legs	pressure mapping technology	N/A