Higosense

Clarification and conceptual design

At the start of the project, the requirements were not clearly defined and there were several technical challenges which we needed to solve in hardware and software. In this phase we developed the five functions independently in proof of concepts: the otoscope, stethoscope, thermometer, skin analysis and throat imaging. Furthermore we were solving several technical challenges, such as the need for high speed data processing through direct memory access, image recognition algorithms and the detailed capture of medically suitable images and sound.

The aim was to validate technical implementations as quickly and efficiently as possible. With these proofs of concept, we were able to medically validate the functions in the field. Also, the concept design of the end product and the UX design were developed and could be validated.

System design

As Higo is a handheld device with multiple functions, the ergonomics of the product and the graphical user interface needed to be well thought through. We have created several design concepts and tested these internally and with potential users (doctors). On a technical level we needed to create a performant and future proof electronics design and embedded software architecture which could support all functions and facilitate high-speed data processing.

Development

The Higo device is based upon a multi PCBA design using flex-rigid PCB connections. The core of the device is an ARM Cortex M7 based STM32H7 MCU with external SDRAM running FreeRTOS using our in-house developed modular built system.

Due to the high data rate requirements in the system and limited power budget we made extensive use of the powerful hardware accelerated peripherals of the MCU. This means that the continuous stream of HD images from the camera is received and converted by the integrated DCMI interface and is directly processed using image recognition algorithms to provide feedback to the user through a custom IPS LCD display connected using the hardware accelerated ART+LTDC interface of the MCU. Besides the image processing flow the device also captures, filters and processes audio and body temperature from the stethoscope and IR thermometer modules.

The resulting exam data is subsequently encrypted and sent wirelessly to the cloud using a combined WiFi/BLE module or stored in the on-board FLASH.

Industrialization

In the industrialization phase, the product was prepared for mass production with a target production volume of 10.000 pieces per year. This phase includes DFM, DFA and DFT for the electronics and mechanical components, where all designs are being analyzed for manufacturability, assembly and testing. Furthermore, all test engineering for electronics and final product (FCT and EOL) was done by Zign Innovations, based on our in-house testing environment. The final production files of Higo have been delivered successfully and are being used to manufacture Higo.

Mass manufacturing

After successful completion of the Industrialization phase, we ensured a smooth transfer to regular mass manufacturing. We are currently a proud supplier to Higo for these products!