# An Interactive Method for Detection of Process Activity Executions from IoT Data +
## 2 Background and Motivation
### Smart Manufacturing Running Example
#### 2.2.1 Smart Factory Model  
We base the running examples on a smart factory model that serves as a typical representative of a CPS [2]. It includes different CPS components (here, production stations), each equipped with a number of sensors and actuators that allow us to demonstrate our approach in a sophisticated IoT environment. The smart factory model simulates a complete production line consisting of the production stations, sensors and actuators depicted in Figure 2. In general, we find the following types of sensors and actuators (cf. Table 1 for a generic and Table 2 for a concrete example) as part of the following CPS components. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Type** & **Name** & **Device** & **Measurement** & **Range** \\ \hline Sensor & i(x)\_pos\_switch & position switch & binary & \{0, 1\} \\ \hline Sensor & i(x)\_light\_barrier & light barrier & binary & \{0, 1\} \\ \hline Sensor & i(x)\_color\_sensor & color sensor & discrete & \{blue, white, red\} \\ \hline Actuator & o(x)\_valve & valve & binary & \{0, 1\} \\ \hline Actuator & o(x)\_compressor & compressor & discrete & [0.. 512] \\ \hline Actuator & m(x)\_speed & motor & discrete & [\(-\)512.. 512] \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Sensors and actuators of CPS components in the smart factory simulation model. * **VGR_1**: The vacuum gripper robot with delivery and pickup station includes the central transportation robot and a station for delivery and pickup of new or produced workpieces. The vacuum gripper emits its current position as triple _current_pos_[_x,y,z]_ and its target position as triple _target_pos_[_x,y,z]_ of continuous values. * **HBW_1**: The high-bay warehouse allows for storage and retrieval of workpieces in containers in a 3 \(\times\) 3 matrix. Its loading robot emits its current position as a tuple _current_pos_[_x,y]_ and its target position as a tuple _target_pos_[_x,y]_ of continuous values. * **OV_1**: The oven allows for simulating the baking of a workpiece. It features a door that can be opened and closed, and a sled to move the workpiece in and out of the oven. * **MM_1**: The milling machine allows for simulating the milling of a workpiece. It features a turntable to move the workpiece inside and outside of the milling area. * **WT_1**: The workstation transport component features a vacuum gripper to transport a workpiece between the oven and milling machine along a slide. * **SM_1**: The sorting machine uses a color sensor to determine the color of a workpiece. It then uses compressors to push the workpiece into one of three ejection bays according to the color. * **EC_1**: The environment and camera station features an RGB camera and a comprehensive environment sensor. The environment sensor provides continuous measurements of air quality (_aq_), gas resistance (_gr_), humidity (_lt_), indexed air quality (_iaq_), relative humidity (_rh_), pressure (_p_), temperature (_t_), relative temperature (_rt_), brightness (_b_), and \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Type** & **Name** & **Device** & **Measurement** & **Range** \\ \hline Sensor & i3\_pos\_switch & position switch & binary & [0, 1] \\ \hline Sensor & i4\_pos\_switch & position switch & binary & [0, 1] \\ \hline Actuator & o5\_valve & valve & binary & [0, 1] \\ \hline Actuator & o6\_valve & valve & binary & [0, 1] \\ \hline Actuator & o8\_compressor & compressor & discrete & [0.. 512] \\ \hline Actuator & m2\_speed & motor & discrete & [\(-\)512.. 512] \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Sensors and actuators of the WT_1 (Workstation Transport) component. Figure 2: Components and layout of the smart factory model, partially adapted from [22] with permission. light-dependent resistance (_ldr_). This station also includes two joysticks for calibration of the smart factory. The design of the physical smart factory simulation model and the separation of CPS components according to the descriptions above are based on the configuration provided in [22].