# Smart Healthcare: Exploring the Internet of Medical Things with Ambient Intelligence
## 3 Sensors and Actuators in the IoMT  
Sensors are the foundation of any IoMT environment. They collect data from the physical IoMT environment and transfer them to communication gateways for storing and analysis purposes. Typically, these sensors can be broadly classified into two categories: body sensors (as shown in Figure 2) and ambient sensors (as shown in Figure 3) [17]. Body sensors collect physiological information such as heart rate, body temperature, blood pressure, blood glucose information, oxygen saturation, etc. By leveraging advanced computational methods, the collected data can be analyzed and interpreted to extract meaningful insights and identify patterns indicative of specific activities or health conditions. Ambient sensors, on the other hand, collect physical information such as gravity, room or outside temperature, humidity sensor, motion sensor, etc. Detailed information on different body sensors and ambient sensors, including sensor type, description, data type, benefits, challenges, and integrations, is provided in Tables 2 and 3. Figure 2: Different body-based IoMT devices. \begin{table}
\begin{tabular}{p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt} p{56.9 pt}} \hline \hline
**Sensor Type** & **Type** & **Invasive?** & **Usage** & **Benefits** & **Challenges** & **Device (If Applicable)** \\ \hline Heart Rate Monitor & W & No & Monitors heart rate & Early detection of cardiac abnormalities & Subject movement can impact accuracy due to noise from inertial force. & Smartwatches, Fitness Trackers \\ \hline \multirow{3}{*}{Blood Pressure Monitor} & \multirow{3}{*}{W/NW} & \multirow{3}{*}{No} & Measures blood pressure & Manages hypertension and cardiovascular risk & Weak signals lead to irrelevant and positioning. & Wearable devices, Automated blood sorens, sleep disruptions, and skin irritation. & Wearable devices, Automated blood pressure cuffs \\ \hline ECG & W & No & Records heart activity & Diagnosis of arrhythmias, heart conditions, mental stress identification & Demands electrode placement and skin preparation. & Wearable devices, ECG machines \\ \hline Blood Glucose Monitor & \multirow{3}{*}{W/NW} & \multirow{3}{*}{No} & \multirow{3}{*}{Monitors blood glucose levels} & \multirow{3}{*}{Diabetes management and glucose control} & Accuracy is affected by factors such as hydration, anemia, site of testing, environmental conditions, extreme hematocrit values or medication interferences. & Continuous blood glucose monitors (CBGM), glucose medium, photography (PPG) device \\ \hline \multirow{3}{*}{Pulse Oximeter} & \multirow{3}{*}{W/NW} & \multirow{3}{*}{No} & Measures oxygen saturation & Early detection of hypoxemia and respiratory issues, detection of sleep apnea & Accuracy can be influenced by poor circulation, skin pigmentation, thickness, temperature, tobacco use, and fingerprint polish. & Wearable devices, Medical oximaters, fingerprint pulse bar \\ \hline Temperature Sensor & \multirow{3}{*}{W/NW} & \multirow{3}{*}{No} & Measures body temperature and infections & Early detection of fever with environment & Requires calibration. Accuracy varies with environment & Wearable devices, Smart thermometers \\ \hline \multirow{3}{*}{Accelerometer} & \multirow{3}{*}{W/NW} & \multirow{3}{*}{No} & Measures acceleration & Activity tracking, fall detection & Accuracy is affected by sensor placement. Policies on zero count data after PA and sedentary time estimation. & Wearable devices, Motion trackers, smartphones \\ \hline Gyroscope & W & No & Measures orientation & Motion tracking, gesture recognition & Measurements drift over time. Sensitive to external factors such as vibration and shock & Smartphones, smartwatches \\ \hline \hline \end{tabular}
\end{table} 
Table 2: List of body sensors used in the IoMT. Figure 3: Various ambient IoMT devices.