# Design and Testing of a Wearable System for Monitoring Car Drivers
## 4 Discussion  
The experience carried out with the prototype of the proposed monitoring device, as reported with the results of the discussed tests, demonstrates potential and limitations in the efficiency and operation of the designed solution. In particular, the potential of the device can be considered in terms of easy wearing and comfort without impediments for car drivers, as shown in the example in Figure 5. The limited size of the units, each contained in a box of approximately 5.5 \(\times\) 5.0 \(\times\) 2.0 cm, also ensures easy portability. Even the relatively low cost, which can be estimated overall at less than EUR 100 for the prototype, much lower than that of existing systems, allows us to foresee the potential success of practical implementation for both vehicle and truck drivers. Limits for practical use can be identified in its structural and functional complexity due to its composition of three independent units; however, these can be easily maintained and managed. The potential of the proposed device is also related to the wide monitoring area with the parameters of motion and physiological reactivity when compared to existing systems which focus mainly on states of drowsiness of vehicle drivers. Data management with direct acquisition of signals and evaluation of the state of aggressiveness by comparison with threshold values makes the ADC calculated using Equation (1) and displayed in Table 1 easy to use with immediate effect. This also presents the possibility of further developments for sound or visual alarm systems that can also be integrated into the same units of the device. This informatic aspect characterizes the functional efficiency of the device, which was designed for use in a system to monitor the aggressive driving of vehicles, due to various reasons, but the physiological monitoring is achievable with few parameters. The parameters used were found to be useful and very efficient in monitoring the driver movement resulting from aggressive conditions, while those more dedicated to the physiological reactivity of the heartbeat and skin reaction did not give the desired results due to evident indications of variations in physiological state. Although the heart rate and skin conductance sensors were found to be inefficient in the proposed device, this evidence can still be considered a significant result of monitoring research and design in the sense that it indicates the need for better sensors of that type or to examine alternatives. The exclusion of heart rate and skin reactivity monitoring in existing devices is not documented by any other studies, and therefore, the result reported in this work can be considered interesting for this purpose. Implementing a monitoring system comprising separate devices, such as the proposed wristband, torso box, and headband, presents several practical challenges despite their individual autonomy. These challenges include the following:  
* Device Management and Maintenance: Each device requires periodic recharging, which can be cumbersome for users, particularly during long driving sessions. Managing multiple devices introduces logistical complexities, as users must ensure that all components are charged and functioning before use. * Comfort and Usability: Although the three device units are designed to be lightweight and wearable for long periods, they could lead to discomfort while driving. The physical presence of the wristband, torso box, and headband may cause distraction or irritation, potentially impacting the driver's experience and driving performance. * Calibration and Sensor Reliability: Calibration is a critical issue to ensure accurate measurements for significant data elaboration. However, discrepancies and malfunctions can occur, necessitating frequent recalibration of sensors. This issue can affect the reliability of the data and the system's overall performance.