Sentinel
Sentinel
Sentinel is part of my Bachelor project, a project made on 1 year in autonomy on a personnal and specific topic, which is the bike security in a rural context.
⏱️ : November - June 2025
👤 : 1 Designer
🧑💻 : UX research, UX design, UI design, Prototyping, 3D design
⏱️ : November - June 2025
👤 : 1 Designer
🧑💻 : UX research, UX design, UI design, Prototyping, 3D design
Context
Context
For both well-being and environmental reasons, and as part of shift toward sustainable mobility, cycling, especially in rural areas, has seen a significant rise (+46% in rural zones since 2025, according to ONISR). Unfortunately, this increase in usage has also come with a rise in road accidents.
For both well-being and environmental reasons, and as part of shift toward sustainable mobility, cycling, especially in rural areas, has seen a significant rise (+46% in rural zones since 2025, according to ONISR). Unfortunately, this increase in usage has also come with a rise in road accidents.
According to ONISR
7%
of fatal accidents are cyclists, around 250 lives that could potentially have been saved.
According to ONISR
7%
of fatal accidents are cyclists, around 250 lives that could potentially have been saved.
The problem
The problem
Several factors contribute to cycling accidents in rural areas:
- Poor visibility
- Bad infrastructure
- High car speeds
- Cyclists' isolation, making them more vulnerable in case of an accident
This reflection led me to the following question:
How can we improve the safety of rural cycling, while taking into account the specific characteristics of the territory and the habits of cyclists?
Several factors contribute to cycling accidents in rural areas:
- Poor visibility
- Bad infrastructure
- High car speeds
- Cyclists' isolation, making them more vulnerable in case of an accident
This reflection led me to the following question:
How can we improve the safety of rural cycling, while taking into account the specific characteristics of the territory and the habits of cyclists?
Research & understanding
Research & understanding
Research & understanding
I focused my research on understanding why cycling in rural areas can be more dangerous than in cities. To dig deeper and identify the root of the problem, I interviewed both a professional and an amateur cyclist.
I focused my research on understanding why cycling in rural areas can be more dangerous than in cities. To dig deeper and identify the root of the problem, I interviewed both a professional and an amateur cyclist.
I focused my research on understanding why cycling in rural areas can be more dangerous than in cities. To dig deeper and identify the root of the problem, I interviewed both a professional and an amateur cyclist.
Interviews
Interviews
Interviews
I interviewed two participants:
– Ramzi, 35, engineer & designer, founder of a start-up focused on improving urban cyclist safety, based in Nantes.
– Oscar, 25, amateur cyclist for over 15 years, mainly rides in rural and isolated areas, based in Toulon.
The main insights gathered are:
– Isolation delays assistance.
– Drivers lack visual alerts.
– Cyclists are looking for a simple, lightweight, and autonomous device.
I interviewed two participants:
– Ramzi, 35, engineer & designer, founder of a start-up focused on improving urban cyclist safety, based in Nantes.
– Oscar, 25, amateur cyclist for over 15 years, mainly rides in rural and isolated areas, based in Toulon.
The main insights gathered are:
– Isolation delays assistance.
– Drivers lack visual alerts.
– Cyclists are looking for a simple, lightweight, and autonomous device.
Challenge
Challenge
Challenge
I framed my project around three specific objectives to best address the issue:
– How can we simplify the alert process as much as possible when a cyclist is involved in an accident?
– How can we optimize the service to reduce the victim’s response time?
– Create a device that further enhances the cyclist’s visibility while ri
I framed my project around three specific objectives to best address the issue:
– How can we simplify the alert process as much as possible when a cyclist is involved in an accident?
– How can we optimize the service to reduce the victim’s response time?
– Create a device that further enhances the cyclist’s visibility while ri
Concept & Process
Concept & Process
Concept & Process
Sentinel is a compact device mounted on the back of the bike, combining:
– Smart fall detection (gyroscope + accelerometer)
– Emergency alert via GSM module with automatic GPS location sending
– Local communication through Bluetooth Mesh (up to 800 m) to warn nearby road users
– Enhanced visibility with high-intensity LEDs visible from 360°
– Manual mode: main button to trigger an alert even without a detected fall
The goal: a fast, reliable, and rural-area-friendly alert system, combining long-range networks (Sigfox, GSM) with short-range communication (Bluetooth Mesh).
Sentinel is a compact device mounted on the back of the bike, combining:
– Smart fall detection (gyroscope + accelerometer)
– Emergency alert via GSM module with automatic GPS location sending
– Local communication through Bluetooth Mesh (up to 800 m) to warn nearby road users
– Enhanced visibility with high-intensity LEDs visible from 360°
– Manual mode: main button to trigger an alert even without a detected fall
The goal: a fast, reliable, and rural-area-friendly alert system, combining long-range networks (Sigfox, GSM) with short-range communication (Bluetooth Mesh).
Small and lightweight
Waterproof and durable
Signal LEDs
Small and lightweight
Waterproof and durable
Signal LEDs
Small and lightweight
Waterproof and durable
Signal LEDs
I also had to address a significant product constraint related to the device itself. For performance reasons, cyclists aim to minimize weight as much as possible. Therefore, it was crucial that the device be compact, lightweight, easy to attach, and, above all, durable enough to withstand falls and harsh weather conditions. These requirements required careful consideration.
I also had to address a significant product constraint related to the device itself. For performance reasons, cyclists aim to minimize weight as much as possible. Therefore, it was crucial that the device be compact, lightweight, easy to attach, and, above all, durable enough to withstand falls and harsh weather conditions. These requirements required careful consideration.
User-flow
User-flow
User-flow
This user flow illustrates how Sentinel works. The elements in green highlight the product’s added value. Today, when a lone cyclist crashes, the time it takes for emergency services to arrive can be critical. Sentinel immediately alerts nearby road users so they can provide initial assistance, which can be crucial.
This user flow illustrates how Sentinel works. The elements in green highlight the product’s added value. Today, when a lone cyclist crashes, the time it takes for emergency services to arrive can be critical. Sentinel immediately alerts nearby road users so they can provide initial assistance, which can be crucial.
By combining these technologies, Sentinel ensures that a cyclist can be quickly and easily located even in very remote areas — a capability often missing from traditional fall detectors.
By combining these technologies, Sentinel ensures that a cyclist can be quickly and easily located even in very remote areas — a capability often missing from traditional fall detectors.
Next part of the project
Next part of the project
Next part of the project
At this stage of the project, although the concept seemed overall well developed, I identified several weaknesses that required a thorough reassessment. For example, the ability to alert loved ones in case of an accident was not included, despite being an essential feature. I therefore had to carefully analyze each functionality of Sentinel to identify and address these gaps, ensuring a solution that is both comprehensive and reliable.
Linking the concept to a mobile app would help address the issues I encountered.
At this stage of the project, although the concept seemed overall well developed, I identified several weaknesses that required a thorough reassessment. For example, the ability to alert loved ones in case of an accident was not included, despite being an essential feature. I therefore had to carefully analyze each functionality of Sentinel to identify and address these gaps, ensuring a solution that is both comprehensive and reliable.
Linking the concept to a mobile app would help address the issues I encountered.
App features
App features
App features
Sports outing sharing
The app records your activity in real time and shares the data with your loved ones when needed.
User visualization
Locate your loved ones in real time, and receive alerts when a Sentinel user is in danger.
Group integration
Create groups within the app to enjoy outings safely together.
Conclusion
Conclusion
Conclusion
Sentinel addresses a specific and urgent need: reducing response times after a bicycle fall in rural areas. By combining automatic detection, proactive visibility, and local communication, this device enhances both the actual and perceived safety of cyclists.
This project taught me:
The importance of simultaneously considering hardware and UX
How to design for a technologically limited environment
The value of local communication in safety devices
However, several challenges slowed down the process:
The technical complexity of integrating multiple communication modules (Sigfox, GSM, Bluetooth Mesh) within a limited space
Hardware constraints to ensure robustness, waterproofing, and compactness, while maintaining strong LED visibility
The difficulty of realistically simulating certain isolated situations to validate system reliability
The need to simplify the interface for quick adoption without sacrificing functionality
These obstacles required numerous iterations and adjustments but ultimately strengthened the quality and relevance of the device.
Finally, this project fits perfectly into my ongoing studies, especially within a master’s program focused on entrepreneurship and technological innovation, where I aim to continue developing concrete solutions that combine design, technology, and social impact.
Sentinel addresses a specific and urgent need: reducing response times after a bicycle fall in rural areas. By combining automatic detection, proactive visibility, and local communication, this device enhances both the actual and perceived safety of cyclists.
This project taught me:
The importance of simultaneously considering hardware and UX
How to design for a technologically limited environment
The value of local communication in safety devices
However, several challenges slowed down the process:
The technical complexity of integrating multiple communication modules (Sigfox, GSM, Bluetooth Mesh) within a limited space
Hardware constraints to ensure robustness, waterproofing, and compactness, while maintaining strong LED visibility
The difficulty of realistically simulating certain isolated situations to validate system reliability
The need to simplify the interface for quick adoption without sacrificing functionality