Cars have become very popular as a mode of transportation ever since their development. In recent years, however, alternate modes of transportation have also become more widely used. For a variety of reasons including cost, health, and eco-friendliness, bicycles and e-scooters are becoming more popular and cities are adapting in order to use them. With more bike lanes and the incorporation of e-scooter stations into cities comes a greater need to recognize these users on the road. However, one current major drawback is the fact that bike- and e-scooter-users are a lot smaller and less obvious than cars on the road at night, and as such, they are far more susceptible to accidents which could also injure these relatively unprotected riders.

Furthermore, we decided this investigation would be best to frame as an engineering design decision.

The General Idea

The procedure below generally outlines how we came up with specific features in our design, but a summary of the technology is as follows. Essentially, we wanted to have the bike rider wear a coat or velcro strap which they would tie around their chest, and this would have some LEDs in the shape of left and right arrows on it. Using motion-sensing technologies (our model used only flex sensors), we would design such that when a person moved as if to turn the steering wheel on their bike or scooter, their motions would be detected and the correct turn signal would be displayed on their back. This allows for bike riders to become more visible to drivers at night without having to do anything more than ride as they usually would. Another benefit of our design is that even though we are using arm motion to determine when the rider wishes to turn left or right, this will not conflict with traditional hand signals. That is, if a person is used to using the L/R hand signals on a bike, their motions in arm bending would still trigger the correct response from the device.


Primary stakeholders: Cyclists and E-Scooter users, who the design aims to benefit by providing a means to protect them from car and motorcycle-drivers on the road, particularly on dark roads. Other drivers on the road including car and motorcycle-users. The design aims to help these stakeholders see the primary stakeholders on the road, and have an idea of where they will be turning. The desired outcome of this is that the primary stakeholders will become more noticeable on the road, and thus less vulnerable to accidents. Pedestrians on the road. The design would also impact this group in that it is easier for them to see the primary stakeholders, and as such road safety will be enhanced for both parties.


Higher-Level Objective: To improve road safety via some technology that will reduce accidents between cars and bicycle and e-scooter users.

(this is not a rigorous set of metrics and criteria, as the nature of a hackathon is that one must turn to many approximations for the sake of time. Given more time for research and development, claims and requirements would be more clearly defined, and more proper resources cited. For the sake of developing some sort of design frame within the given time, however, we chose to stick with the following as notes to keep in mind as we build this design.)

Lower-level objectives, and corresponding metrics, criteria, and incorporated design decision based on previous information + improvements to be made with more time:

1. For the design to increase the visibility of bicycle and e-scooter users to other people on the road. Metric 1: Whether the design incorporates lights (of approximately the size of normal turn signals) onto the user. Criteria: Presence of this metric is preferred. Incorporated Design Decision: Lights mounted on the body of the design enhance the visibility of the user to others on the road. Back-light component remains to be incorporated, such that all-around visibility of the user will be achieved.

2. For bicycle and e-scooter users to be able to indicate their direction of travel via turn signals (ie. left/right turn signals) M2: Whether the design incorporates a method for users to communicate signals. C: Presence of M2 preferred. Incorporated Design Decision: Light signals activated by user motion incorporated in the design to communicate turn signals and make them obvious to all road users.

3. For the design to not inhibit the user’s ability to safely operate their bicycle/e-scooter, by not requiring the user to do more than their usual hand-gestures while operating the vehicle. M3: Whether the design requires the user to remove their hands from the handles for longer than a few seconds. C: Lack of M3 preferred. Incorporated Design Decision: The hands-free design of the device allows the user to easily improve their ability to communicate with others on the road without having to sacrifice their ability to travel without additional handicaps. The overall design will be improved to minimize bulkiness, and to enhance ease of wearing through better incorporation with the jacket and increased lightness of the design.

4. For the user to be able to operate the design through typical hand-gestures that would be expected to be used on the road. (ie. design to require minimal additional knowledge to operate) M4: Whether the design requires more than common hand gestures to be operated. C: No is preferred. Incorporated Design Decision: The incorporation of motion-sensing technology via flex sensors allows the user to effortlessly use the device alongside their conventional turn-signals to enhance their ability to communicate their moves to other road users.

5. For the design to recognize different motions of the specific user and respond by displaying the correct turn signals. M5: Whether the device can adjust its responses based on the degree of arm flexing the user typically has when riding normally/ signalling turns. C: Yes preferred. Incorporated Design Decision: Current setting based on the degree of flexing of the tester. This shows to work after setting up correct measurements and ranges for each person, however expansion to accommodate different types of users remains to be done.

This would be simply achieved. The device setup would require an initial testing where the user wears the device as they ride their bike or e-scooter, and to make turn signals with each arm when indicated by the device’s setup program. The device would measure the degree of flex throughout this testing, and store the data. Thus, the device would be capable of responding more accurately to the unique motions of the user, and give the correct turn signals based on the current user situation.

6. For the design to be easy to turn off and on as needed, so that it works only when necessary. M6: Whether the design has an easily accessible switch. C: Presence preferred. Incorporated Design Decision: The switch is mounted onto the sleeve to support the design for ergonomics. The ability to easily activate or deactivate the device as needed makes the design adaptable to different situations. Since the lights can be integrated more aesthetically into a jacket, it also becomes easy for users to wear the device both comfortably and fashionably (so they won’t feel awkward wearing it).

How we built it

A combination of Arduino coding, circuit calculations, and many many iterations led us to the final design. We developed ideas for matters we wanted our design to address as well as ways for these goals to be accomplished (as outlined in the design decision portion of this document), and we attempted to create as much of our design as we could using the limited time we had. We were proud to develop our prototype, and look forward to showing it off to the judges!

Challenges we ran into

Soldering and wiring were our biggest challenges. Many times we had to go over the circuits and find where there was a short-circuit causing problems with the LED, but eventually we managed to correct all of that. Furthermore, figuring out how best to work the flex sensors and how to mount them into the design as well as deciding what reading on the sensor should be considered 'flexed' was also quite the challenge. The latter component of the issue was what inspired us to consider technologies that would decide these factors based on inputted user data. That is, the device would initially be worn by a user who would tell the device when their arm was flexed or not, and the settings would take these initializing values for future prediction of movement.

What I learned

Each of us was good at a different thing, whether it was circuit building, software, or sewing parts onto a hoodie. We all came out learning a bit about what each other member had to contribute to the group, and we are proud to have accomplished what we did during this short period of time.

What's next for Team 18 - GO TEAM

We hope to continue learning, and finding more opportunities to develop engineering designs which could potentially benefit society. This particular project we want to also continue improving upon, as we have more ideas and want to see how they could grow given more time. We generally look forward to gaining more skills as we continue attending hackathons, and to hopefully creating something meaningful which can positively contribute to society!

Share this project: