OneSun Final Report- BME 440
Business proposal
Project overview, objectives, major milestones and schedule
OneSun will provide users with a reliable, wearable device that will remind them when to reapply sunscreen. Unlike other products currently on the market, our product is the only one that utilizes UVA reflectance technology, giving us a direct quantitative measurement of sunscreen effectiveness. Currently, our team at OneSun has developed a detailed design schematic and ordered all of our parts needed to create our first prototype which will be assembled in January. Although, we are yet to receive all the parts for our prototype, we have begun building with a UV sensor and bluetooth component:
Figure 1: First attempt at our prototype; includes Arduino, UV sensor, and Bluetooth Low Energy (BLE)
Market Need and Potential
The market OneSun is looking to target is the large number of sunscreen users in the United States. According to a Consumer Reports study in 2008, 69% of Americans claim to wear sunscreen on occasion. According to this study, that gives us a potential market of 222 million Americans. OneSun would like to reach approximately 5% of this market, giving us a potential market size of 11.1 million customers [1].
Product Proposal
OneSun proposes a wearable and waterproof band that reminds users when to reapply sunscreen. Our product will come equipped with a UVA LED and a UV Sensor that will directly measure the reflectance of UVA off the skin of the user, giving us a direct quantitative measure of the effectiveness of their sunscreen. The device is initialized by measuring the UVA reflectance of the skin with and without sunscreen. After initialization, OneSun will continuously measure UVA reflectance of skin surface. Once the UVA reflectance drops below a certain threshold, OneSun will vibrate, notifying the user to reapply sunscreen.
Strategic Fit
Current mainstream products on the market only provide an estimated measure of when the user needs to reapply sunscreen by measuring only environmental UV exposure. However, OneSun will be the only product to utilize our skin reflectance technology to obtain a direct measure of the effectiveness of the user’s sunscreen and let them know when it is time to reapply. We will provide our customers with a durable, reliable, comfortable, and affordable product. Our device will come equipped with a lightweight, waterproof adjustable band with a solar-powered battery for under $60.
Risk Assessment
Business-wise, the main risk to OneSun is the reliability of the product. Naturally, customers will be turned off if the product gives false alerts, or worse, no alert. The accuracy of the UV reflectance technology we propose to use can potentially be marred by various constraints:
- Some sunscreens are designed to scatter light. In this case, the reflectance reading may not be an accurate representation of the UV reflectance.
- OneSun will be located in one part of the body and will also cover that part. So, it won’t directly represent the UV reflectance for the rest of the body.
These questions about reliability would have to be answered via heavy experimentation and the development of algorithms that take all the constraints into consideration.
In addition, we envision OneSun to be a seasonal product with most of the sales coming during periods of heavy sunshine. This provides some risk for our product being unnecessary for users during the colder, winter months. However, we plan on educating the public via marketing about the dangers of UV exposure during seasons other than Summer.
Economic Analysis
The total projected cost of assembling parts and manufacturing a single product is around $30. We are pricing the OneSun at $60 each, which will result in about a $30 profit for each unit sold. Out of the 322 million people currently residing in the United States, 69% claim to wear sunscreen on occasion, leaving us with approximately 222 million potential customers. We want to initially reach 5% of that number, which is around 11 million people. That’s a potential market of half a billion dollars and more (200+ million in profits if we sell that many units).
At OneSun, we are also looking towards the International market as a potentially lucrative one. The amount health conscious customers who are choosing to use wearable sensors is on the rise. Enabling factors such as the reducing price of sensors, improved wireless connectivity and low energy consuming technologies (i.e. Bluetooth Low Energy) have contributed towards making wearable sensors affordable mainstream options for consumers. The worldwide market is projected to undergo a dramatic rise. A recent report projected the production of 3 billion wearable sensor units by 2025 with 30% of them from new sensor technologies [2].
Introduction and Background
Skin cancer is currently the most prevalent cancer in the United States [3]. It is the uncontrolled growth of abnormal skin cells. Skin cancer occurs when a stressor, such as ultraviolet radiation from the sun, cause mutations and genetic defects leading to rapid abnormal skin cell proliferation and tumor growth [3]. The exposure to ultraviolet radiation can be brief and intense when an individual steps outside without proper skin protection. According to the Skin Cancer Foundation, 42% of individuals will get sunburned at least once a year, and a person’s risk for melanoma will double after five sunburns. Individuals can protect themselves from harmful ultraviolet radiation by using sunscreen, but only if it is reapplied frequently. Currently, sunscreen products give their users an estimate of when they should reapply their sunscreen with something called an SPF. SPF stands for Sun Protection Factor. Everyone has a natural SPF, which can be obtained by estimating the average amount of time (in minutes) that it takes for your skin to burn. In order to determine the amount of time a user can wait before reapplication, sunscreen users must multiply their natural SPF by the one given on the bottle. However, there are many limitations to this process. The main problem is that this value is only an estimate, and therefore does not take into account factors that can cause the reapplication time to vary such as the UV index and exposure, swimming, towel drying, and sweating. As a results, many sunscreen users fail to reapply their sunscreen in time and find themselves sunburned by the end of the day. In order to solve this problem, our team at OneSun has developed a product that allows users to obtain direct quantitative measurements of the effectiveness of their sunscreen. With our product, users will no longer need to estimate a reapplication time or worry about getting sunburned because OneSun will let them know directly.
Design History
We are targeting a percentage of all occasional sunscreen consumers who have specific customer needs. We will also have to keep in mind the technical constraints that come with designing such a product. We have research similar products that are popular in the market and observed the online reviews. Going over these reviews, it became clear to us that six essential properties were the make or break factors for the consumers. Scaling from the highest priority to lowest, these needs included: reliability, durability, adjustable length, affordable price, lightweight, comfort, and style. These six ‘customer needs’ are shown in the Quality Function Deployment (QFD) table below. QFD is a tool that puts into perspective the relations between the customer needs and technical requirements. This allows us to see the bigger picture before making design decisions. Reliability and durability were ranked number 1 and 2 in our customer needs since we found that most of the customers were not satisfied with the accuracy of the sensors or the life of the products in the online reviews.
In our QFD table, the top three customer needs are reliability, durability and an affordable price. These three have stronger correlations to the technical requirements compared to the other customer needs in the body matrix. Fortunately for us, this means that we can focus our energy towards these needs and produce a customer friendly product. The OneSun will be a product that will be worn outdoors in harsh environments for electronics (i.e. beach). It will also be operating for lengthy periods, periodically checking for sunscreen deteriorations. To survive these challenges OneSun must be reliable and durable; with good battery life and waterproof design. The affordability of the product will be determined by the technical qualities of the product: battery life and data acquisition. We will utilize the majority of our time in optimizing these two factors without negatively affecting the affordability.
The roof of the QFD table shows the correlations between technical requirements. As seen below, there is a strong positive correlation between biocompatibility and a waterproof design. Therefore, we have to choose a material that fulfills these two requirements. Since battery life has a negative correlation to fast data acquisition, we must be take this into consideration when designing the product.
Currently, our design priority is to build the first product prototype and run numerous experiments to gauge the response of the product to different variables. The UV reflectance detection we propose to use has not been used before in UV sensing devices. Besides that, certain factors of our design (i.e. the sensor only covering a small part of the overall body & the sunscreen on the skin under the sensor being protected from the environment unlike the rest of the body) have to be observed in action and we have to optimize the design further to get reliable results in any conditions. Our prototype will rely on the Arduino program during the alpha stage. So, we have to work with coding languages used in Arduino.
We are looking at a rechargeable battery system as an alternative to our proposed solar powered batteries since we had difficulties finding a solar powered battery small enough to fit our lightweight design. The design of the actual sensor and the adjustable band has not been finalized yet. For the band, we are looking at conventional leather watch band designs with holes and buckles, flexible metal chains design and also a snap on magnetic band.
Figure 2: QFD Body Matrix: Correlation between customer needs and technique requirements
Product Specifications
Customer Need / Product SpecificationReliable Product /
- Minimum 10 hrs Battery Life
- Direct reflectance measurements taken at pulses at 1/60 Hz for a duration of 30 ms
- Notification by vibration with maximum 5 sec delay.
Durable /
- Water-tight design (under 130 ft of water, avg depth for Scuba Diving)
- Strong material (i.e. Aluminium Alloy)
Affordable /
- Slow data acquisition (1/60 Hz)
- Low cost material/components (Free 3D printing)
Comfort and Style / Wearable, biocompatible material, lightweight material, latex free and hypoallergenic. Bands available in different colors.
Table 1: Product specifications based on customer needs
Design Specifications
Requirements / Design SpecificationDirect quantitative sunscreen effectiveness measurement / Direct reflectance measurements:
- Adafruit UV Index Sensor (400-800nm, UV Index scale of 0 to 15 [4])
- UVA LED (400 nm) pulses at 1/60 Hz for duration of ~30ms.
Notification / Piezoelectric Buzzer will vibrate once intensity of reflected UVA to the detector is below threshold (Threshold is variable and to be determined via future studies)
Durability / Water-tight design (Titanium alloy material)
Long-lasting solar-powered battery
Worst-case battery: minimum of 3.7 V and 8 hours durability with 1/300 Hz data acquisition (worst-case data acquisition).
Reliability / Bottom of device is elevated (as seen in Fig 2) to allow room for UV pulse to be directed onto skin and measured by UV sensor
Solar-powered battery
Worst-case: If we are unable to find a small solar-powered battery that fits the lightweight requirement of our design, a rechargeable battery will be used.
Comfort and Style / Wristband, biocompatible material, lightweight material
Table 2: Design specifications to meet product specifications
Design Description
As seen in the schematic below, the 4 main components of our device are a UVA LED, UV detector, battery and piezoelectric buzzer, all enclosed within a waterproof case. The dimensions of OneSun are anticipated to be 43x37x14 mm. The device can be joined to a detachable and adjustable wrist band. The flexibility of using a detachable band allows the user to measure loss of sunscreen in parts of the body other than the wrist region, when OneSun is detached. Hence, the device alone is a clip. When the bracelet is securely strapped, the device will be slightly elevated on the skin surface. This is to provide room for the UVA LED beam to be directed towards and reflected from the skin for detection by the UV sensor. The UVA LED is positioned at an angle to allow for improved UV detection as opposed to having the UV LED directed perpendicularly to the skin surface. The opening that permits UVA to be directed onto the skin will be as small as possible (~1mm diameter). OneSun must be initialized prior to use by measuring the UVA reflectance of skin surface with and without sunscreen. This establishes a UVA reflectance range specific to each user. Once the UVA reflectance drops below a certain threshold, the piezoelectric buzzer will vibrate, thus notifying the user to reapply sunscreen. The battery is rechargeable and in the event that we have extra time and resources, we intend to build a charger for OneSun.
Figure 3:Design schematic for bottom of bracelet, include UVA LED, UV sensor, battery, and piezoelectric buzzer for notification
Figure 4: Design schematic showing UV reflectance technology
Figure 5: Design schematic including dimensions
Part List and Cost
Adafruit UV Index Sensor$10.00
UVA LED$0.50
Mini breadboard$4.00
Piezo buzzer$1.50
PCB$5.00
Battery $6.00
References
- Skincancer.org
1