HomeEngineering Projects For YouSmart Body Fat Scale Reference Design

Smart Body Fat Scale Reference Design

The scale measures body fat, BMI, and more, using sensors and smartphone connectivity for health management.

smart body fat scale

In contemporary society, individuals are closely monitoring their health metrics, including body weight, body fat percentage, and overall body composition. This heightened health consciousness has spurred the popularity of body fat scales. Renesas’ Smart Body Fat Scale solution stands out in this space, offering a user-friendly means to track health data such as body fat. The scale is adept at measuring body impedance and is equipped with four weighing sensors and four metal electrodes. When users stand on these electrodes, their body impedance is gauged through an impedance detection circuit. This data, combined with personal details like height, gender, age, and weight, allows for precise calculation of body fat and other vital health parameters. These measurements are displayed on an LCD monitor for immediate viewing and can be accessed and monitored through a smartphone application, enabling seamless health management.

Renesas has launched a smart body fat Scale reference design to simplify the design process. This design incorporates the RL78/L1A Microcontroller Unit (MCU), which is equipped with extensive analogue peripherals and a Liquid Crystal Display (LCD), along with the RL78/G1D MCU’s Bluetooth Low Energy (BLE) communication functionality. This combination makes it suited for healthcare bio-sensing applications. The company says that the solution is a non-medical device.

- Advertisement -

The demonstration board for this system includes the RL78/L1A (a microcontroller unit) and the RL78/G1D module. The RL78/L1A microcontroller is equipped with a Flash Read-Only Memory (ROM) size of 96 Kilobytes (KB) and a Random Access Memory (RAM) size of 5.5KB. This setup is designed to work with a smartphone application, enabling communication with the Smart Body Fat Scale via its integrated Bluetooth module. The scale features four weighing sensors for accurate weight measurement and four metal electrodes for body impedance measurement, employing the Bioelectrical Impedance Analysis (BIA) technique. It can display a range of health metrics, such as body weight, body mass index (BMI), body fat percentage, and body impedance. Power for the system is provided by four AAA batteries, ensuring both portability and ease of use.

To showcase the application’s functionality, it’s necessary to program both the BLE protocol stack and the application software into the RL78/G1D module and RL78/L1A microcontroller, respectively. Following this, by installing a compatible app on an Android smartphone, communication can be established between the smartphone app and the smart body fat scales via BLE (Bluetooth Low Energy) function. The app is designed to receive scales’ weight and body impedance data. It then integrates this data with user-entered information such as height, gender, and age to calculate and display the body fat percentage.

- Advertisement -

Renesas have tested this reference design. It comes with a Bill of Materials (BOM), schematics, etc. You can find additional data about the reference design on the company’s website. To read more about this reference design, click here.

Nidhi Agarwal
Nidhi Agarwal
Nidhi Agarwal is a Senior Technology Journalist at Electronics For You, specialising in embedded systems, development boards, and IoT cloud solutions. With a Master’s degree in Signal Processing, she combines strong technical knowledge with hands-on industry experience to deliver clear, insightful, and application-focused content. Nidhi began her career in engineering roles, working as a Product Engineer at Makerdemy, where she gained practical exposure to IoT systems, development platforms, and real-world implementation challenges. She has also worked as an IoT intern and robotics developer, building a solid foundation in hardware-software integration and emerging technologies. Before transitioning fully into technology journalism, she spent several years in academia as an Assistant Professor and Lecturer, teaching electronics and related subjects. This background reflects in her writing, which is structured, easy to understand, and highly educational for both students and professionals. At Electronics For You, Nidhi covers a wide range of topics including embedded development, cloud-connected devices, and next-generation electronics platforms. Her work focuses on simplifying complex technologies while maintaining technical accuracy, helping engineers, developers, and learners stay updated in a rapidly evolving ecosystem.

SHARE YOUR THOUGHTS & COMMENTS

EFY Prime

Unique DIY Projects

Truly Innovative Electronics

Electronics News

Latest DIY Videos

Electronics Components

Electronics Jobs

Calculators For Electronics