Wouldn't it be convenient if you could see your physical condition every day?

"I want to detect any physical abnormalities as quickly as possible."
"I want to live and work more comfortably and safely."

In response to such needs, the use of wearable devices is rapidly expanding.

Macnica Manufacturing Consulting (MonoCon®) has been involved in multiple wearable device development projects as a technology partner that can provide end-to-end support from sensor design and component selection to circuit design, mass production, and procurement. Here, based on several case studies, we will introduce the specific support we provide and how we support "technology that listens to the body's voice."

The development requirements for wearable devices vary depending on their intended use.

The development requirements for wearable devices vary greatly depending on their intended use.

• Occupational safety: Robustness in harsh environments, real-time communication, and sustained working hours (8 hours)
• Medical Clinical Applications: High-precision vital sign measurement, compliance with medical device regulations, and continuous operation for 24 hours or more.
• Fitness/Consumer Use: Balancing design, comfort, and mass production costs.
• Healthcare/Wellness Management: Lightweight for everyday wear, battery lasts for several days, smartphone connectivity.

Lumping all "wearable" devices together can lead to misjudging requirements during the planning stage. This article explains the development requirements matrix by application, three common hurdles that arise regardless of application (battery, miniaturization, and communication), and even the selection of a vendor, using real-world examples from MonoCon®'s actual development experience.

Related articles How to choose the right outsourcing method for product development, Five patterns of failure when outsourcing the development of electronic devices Please also refer to the following.

[Comparison Table ①] Development Requirements Matrix by Application

Even with the same wearable device, the starting point can be completely different depending on whether or not regulatory compliance is required, such as battery requirements of several days vs. 8 hours, or waterproof requirements of IPX4 vs. IPX8. Narrowing down the application to one (or separating development by application) at the planning stage is a prerequisite for success.

Where does our company's application fit in?

By arranging the four applications in a 2x2 grid, with the vertical axis representing the strictness of regulatory requirements and the horizontal axis representing the length of wear time, you can see at a glance which quadrant your company's application falls into.

The bottom right quadrant (long duration x lax regulations) represents the largest market, with competition between healthcare and consumer products. The top right quadrant (medical clinical applications) sees significant development costs due to stringent regulatory compliance. The bottom left quadrant (occupational safety) offers short wear times but presents high challenges in terms of robustness and real-time performance.

Application A: For occupational safety (heatstroke and fall detection)

Market needs
The revised Industrial Safety and Health Regulations came into effect on June 1, 2025, requiring stricter vital sign monitoring of workers in harsh environments. This has accelerated the adoption of wearable devices for heatstroke prevention, fall detection, and location/movement monitoring in construction, logistics, and manufacturing sites.

Required technology
- Continuous measurement of body temperature, heart rate, and acceleration.
• Battery that lasts for the duration of work (8 hours or more)
- Real-time transmission to the cloud via gateway
• Durability against harsh environments (sweat, rain, impact) (IPX4 or higher)

Implementation Reality
It's difficult to satisfy both the requirement of being comfortable to wear and having sufficient robustness. A heavy, bulky casing is unpleasant to wear, while a lightweight, thin design compromises durability. Selecting a mounting method that suits the work environment, such as helmet-integrated, armband, or clip-on types, is key to the initial decision. For communication, since the Wi-Fi environment at the work site is often unstable, gateway-aggregated systems such as LTE-M/Sub-GHz are also an option.

Application B: For medical and clinical use

Market needs
The expansion of DCT (distributed clinical trials) is increasing the demand for wearable devices that can continuously collect vital data without the supervision of healthcare professionals.

Required technology
• Medical-grade measurement accuracy
- Continuous operation for more than 24 hours
• Highly reliable real-time communication
• Compliance with medical device regulations

Implementation Reality
Whether a wearable device qualifies as a "medical device" depends on its intended use.

- Provided as "reference information for health management" → General-purpose wearable
- Purpose of "diagnosis, treatment, and prevention of disease" → Subject to medical device regulations (PMDA regulatory approval)

The boundary between medical devices and general-purpose wearables must be clearly defined in the early stages of development. Changing course midway through development to "make it a medical device" is virtually impossible. It would necessitate redesign and certification, significantly increasing development costs and time. Macnica MonoCon® specializes in the development of general-purpose wearables, but also handles the design and manufacturing of medical devices.

Application C: Fitness/Consumer

Market needs
For consumer products such as smartwatches, smart rings, and sports patches, design and branding are the main motivations for purchase.

Required technology
- Basic functions such as heart rate, steps, and calories
• Lightweight, compact, and comfortable to wear
• Casing design that aligns with the brand
• IPX5 to IPX8 water resistance (suitable for swimming and diving)

Implementation Reality
For consumer products, it's necessary to develop the electronic circuitry and enclosure design in parallel. This is because the board size, antenna placement, battery placement, and sensor placement are all linked to the enclosure shape.

▶ In the development of a bangle-type wearable device, we collaborated with an external design partner to create the casing design, which was then progressively verified using 3D-printed mockups. This is an example of how we were able to successfully design a casing with a unique shape that houses electronic circuits by refining the electrical design and casing design simultaneously.

Application D: Healthcare/Health Management

Market needs
There is a growing demand from companies to visualize the health status of their employees. The global wearable device market is said to be worth 30 trillion yen, and investment in everyday wearable devices is increasing amid the trend of health management combined with data utilization.

Required technology
- Continuous measurement of heart rate, activity level, sleep, and SpO2
• Battery design that lasts for several days to a week
BLE (Bluetooth Low Energy) connection with smartphone
・Daily waterproof (IPX4 to IPX7)

Implementation Reality
The biggest challenge is the trade-off between battery life and measurement frequency. Continuous measurement will result in the battery not lasting even a day, while intermittent measurement (e.g., every 10 seconds) extends the lifespan but reduces detection accuracy. To create a user-friendly device, the measurement frequency, communication interval, and sleep mode design must be determined based on power consumption profiling.

▶ In one case, the power consumption issue remained unresolved, and the realization that they wouldn't have proceeded with mass production if they had known about it before the prototype stage was reached. Subsequently, improvements in power consumption were found to reduce it by 10%, assuming system stabilization, demonstrating that continuous improvements in power consumption are necessary at each prototyping stage.

Common obstacles in wearable device development

Regardless of the intended use, there are common hurdles that inevitably arise in the development of wearable devices.

Difficulty ①: Battery life (power consumption profiling)

The biggest headache in wearable device development is battery life. Wearable batteries are typically a few hundred mAh or less, and they won't last a full day with "continuous measurement + continuous communication." Designing them to extend lifespan through intermittent measurement + low-power communication (BLE) is essential. Microcontroller selection also requires balancing cost, technical compliance requirements, and low power consumption.

As mentioned earlier, in the development of a certain general-purpose wearable device, power consumption became the biggest obstacle, causing hesitation to move to mass production prototyping. It is essential to conduct power consumption profiling at each prototyping stage and continuously optimize the measurement frequency, communication interval, and sleep mode design.

Difficulty ②: Miniaturization (components cannot be mounted on the circuit board)

The sensor, microcontroller, communication module, battery, and charging circuit must all fit into a space of just a few centimeters square. Standard practices include the active adoption of SoCs (System on Chip), the use of 4-6 layer multilayer circuit boards, flexible circuit boards, and the use of ultra-small 0402-size chip components.

Difficulty #3: Stability of BLE communication (the human body absorbs radio waves)

BLE connectivity becomes unstable when the device is worn on the body. Measures such as positioning the antenna as far away from the body as possible, conducting radio wave measurements while the device is worn from the early stages of development, and considering a design that combines BLE with I2C communication are necessary.

Furthermore, changing the antenna position to an external location means that certification under the Radio Law must be obtained again. Certification, including verification and display requirements for the BLE module's technical compliance number, is an issue that should be incorporated from the design stage.

[Comparison Table ②] Three Patterns for Selecting a Contractor for Wearable Development

For healthcare/fitness, a one-stop solution is ideal if design is a priority; for rapid implementation, a module-based solution is best; and for compliance with medical and clinical regulations, either an ODM (Original Design Manufacturer) or a one-stop solution is appropriate. The choice depends on the application and purpose.

Macnica MonoCon®'s Wearable Development Support Area

MonoCon®'s role is to handle and consolidate all the necessary steps in wearable device development—from planning and design to prototyping, mass production, and maintenance—through a single point of contact. Here are some specific examples of our support services.

Selection of safe and secure materials

In a wearable development project with a certain company, we developed a device that is worn on the human body to continuously monitor the body's condition. In this project, reducing the risk of allergic reactions was a crucial challenge in selecting materials for parts that come into direct contact with the skin. We proposed materials with a proven track record in medical applications, achieving both safety and comfort during wear.

In selecting the materials, we negotiated directly with manufacturers to find a resin material that was not only gentle on the skin but also balanced softness and strength, enabling us to design a wearable device that can be used safely by everyone from babies to the elderly. Furthermore, we conducted numerous tests to ensure that the material would not deform or discolor due to sweat or sunlight.

Through these efforts, we were able to create high-quality wearable devices that prioritize the health and safety of our users.

Realization of long-term continuous operation (low power consumption)

Furthermore, we actively worked to reduce the power consumption of the sensor module, aiming for stable operation in field environments and long continuous operation on a single charge. In particular, by adopting an ultra-low power consumption CPU, which Macnica handles as a distributor, we succeeded in significantly reducing power consumption while enabling continuous operation of the sensor.

During firmware design, we encountered numerous challenges related to power consumption, such as optimizing operating modes and sleep control. However, through the Company technical support and a collaborative system involving the manufacturer's engineers, we were able to provide consistent, high-quality support from the initial design phase to the mass production phase, achieving the low power consumption that our customer desired.

Furthermore, in battery selection, we faced an unexpected situation when the battery we initially planned to use suddenly became unavailable due to its end-of-life (EOL). However, we quickly proposed and procured alternatives from battery manufacturers around the world, minimizing design changes and avoiding project delays. This ability to communicate with manufacturers worldwide and respond flexibly and quickly is one of our capabilities.

The design makes it easy to wear, making you want to wear it

Beyond high performance, the ability to make wearable devices desirable is essential for their widespread adoption. As mentioned earlier, recent products prioritize user comfort, using materials that reduce skin irritation, allergy-friendly resins, and IPX7 or higher waterproof designs, but improvements have also been made in terms of appearance, sleekness, and lightweight feel.

​MonoCon® brings together designers who have worked on designs for well-known products to create stylish designs that resonate with users' sensibilities. Furthermore, by collaborating with manufacturing partners who can faithfully realize those designs, we are able to develop products that combine both functionality and beauty.

If the device has a stylish design rather than looking like a typical medical device, it won't be embarrassing to wear all the time. In childcare settings, some devices incorporate sensors inside stuffed animals so that children won't mind wearing them.

As an example, we created a mockup of smart glasses, as shown in the photo below.We started by commissioning a designer to create design drawings, shared the final image with renderings, and the mockup, which was actually manufactured using a 3D printer, turned out to be very satisfactory.Furthermore, we can add our own unique touches to the mockup. In this case, we refined the paintwork to achieve a color that more closely resembled the final smart glasses. For example, the glasses were painted in a bluish-black color, with a metallic finish achieved through color mixing, while the band was given a matte finish by changing the texture. By incorporating various requests, we can create something that is closer to the final product image.

Design drawing

Rendering

Mockups made with a 3D printer

"Proactive safety management" achieved through sensors, cloud computing, and AI

Macnica 's cloud technology also supports systems that link vital data and environmental information collected by sensors to the cloud in real time, and immediately notify administrators of alerts when abnormalities are detected. Unified management of sensors and the cloud eliminates variations between sites and serves as the foundation for optimal safety measures.

In addition to real-time warnings, AI can also analyze accumulated vital signs data to predict which times and tasks are dangerous.

For example, on one production line, it became clear that the risk of accidents tended to increase after lunch breaks, and by moving work hours forward, the accident rate dropped significantly. Sensors are no longer just monitoring tools; they are also beginning to demonstrate their value as tools for predicting the future. Accumulating data and making predictions makes it possible to move towards "proactive safety management."

Integrated support from procurement to mass production

In terms of parts procurement, we also support overseas procurement and manufacturing (so-called OUT-OUT) with a view to the global market. To prepare for supply instability due to climate change and geopolitical risks, we have secured procurement routes from multiple regions both domestically and internationally in advance, creating a system that can flexibly respond to sudden supply disruptions.

Furthermore, even in the mass production phase, we can establish an overseas manufacturing system in cooperation with local EMS (Electronics Manufacturing Services). By optimizing the circuit and enclosure from the design stage, taking into account mountability and assembly man-hours, we ensure smooth on-site inspection and mass production startup. Our know-how in overseas mass production of a wide variety of products in small lots supports both cost competitiveness and supply stability.

Frequently Asked Questions (FAQ)

Q1. How much does it cost to develop a wearable device?

The cost varies greatly depending on the application and complexity. PoCs starting from several million yen are possible, and we will first provide an estimated quote after a consultation.

Q2. What is the designed battery life?

It depends on the measurement and communication frequency. With measurements at 10-second intervals plus BLE transmission, it is technically possible to operate the device for several days to a week even with a small 200mAh battery. For continuous measurement and communication, one day is a more realistic upper limit. To ensure "sustainability for one shift (8 hours)" in occupational safety applications, power consumption profiling and design based on usage patterns are essential.

Q3. What level of waterproofing can be achieved?

We can design devices to meet your specific requirements, from IPX4 (splash-proof) to IPX8 (submersible). Macnica has a track record of implementing IPX7-equivalent waterproofing and materials that meet medical standards. However, since higher waterproofing ratings increase cost, size, and weight, it is important to select the optimal rating for your intended use.

Q4. How long does the development process take?

While a proof-of-concept (PoC) can be completed in a few months to half a year, getting to mass production can sometimes require an estimate of several years. The prototyping stage progresses in stages, with repeated design modifications and evaluations at each stage.

Q5. Can you also handle cases where we want to sell it as a medical device?

Responding to medical device regulations requires collaborating with regulatory experts to determine design policies in the early stages of development. MonoCon® specializes in supporting the development of general-purpose wearable devices and provides initial consultations, including assessment of medical device classification. Since a change in policy to medical device classification midway through development will necessitate redesign and certification, it is crucial to make this determination at the planning stage.

To stay one step ahead in development, you need a reliable partner

The success or failure of wearable device development largely depends on "narrowing down the application to one at the planning stage and accurately estimating the requirements necessary for that application." To summarize the key points for each application:

• Occupational safety → Continuous operation for one shift (8 hours), real-time communication, robustness, compliance with revised labor safety regulations.
• Medical and clinical applications → High-precision measurement, 24-hour continuous operation, and early clarification of medical device regulatory boundaries.
• Fitness/Consumer-oriented → Design, simultaneous design of electronics and enclosure, mass production cost
• Healthcare/Wellness Management → Battery life of several days to one week, BLE connectivity, comfortable fit

And across all applications, three common challenges inevitably arise: battery life, miniaturization, and communication. Choosing a partner who can manage all of these—from planning and design to prototyping, mass production, and maintenance—through a single point of contact will determine the success or failure of the development.

If you're having trouble developing wearable devices, please consult MonoCon®.

"I don't know where to start technically."
"The specifications haven't been finalized yet, but we'd like to discuss it from the conceptual stage."

Even at that early stage, we can help. Delivering the optimal technology to those who need it, without any hassle, is the foundation of our manufacturing support. As a reliable partner for companies challenging themselves in wearable device development, we continue to support them from concept to implementation and mass production with our solid technology and flexible response capabilities.

Recently, wearable devices for babies, the elderly, and pets are also being developed. Even just considering heatstroke prevention, systems are being considered that would automatically activate cooling materials when a rise in body temperature is detected, and simultaneously send an alert to the caregiver, for use in strollers, wheelchairs for the elderly, and beds.

​MonoCon® is a group of electronics development professionals that excels under these complex conditions. We provide optimal support in every phase of manufacturing, from material selection and circuit design to enclosure manufacturing, component procurement, evaluation, and mass production.

If you're having trouble developing wearable devices, please consultMacnica MonoCon®.

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