HMI
Medico & Life science
Case

Engineering and manufacturing of a wearable keypad

31. March 2024

For their patented grip-strengthening glove, Bioservo needed an HMI partner to deliver a complete HMI assembly

Bioservo’s patented Carbonhand, ensures that users can grab, for example, a cup or a pen.. Carbonhand consists of a glove with built-in pressure sensors that register when the hand grabs onto things. The glove is equipped with a small control keypad on the wrist. Our collaboration with Bioservo was concentrated around engineering, prototyping and manufacturing of the keypad.

"It is a great strength that Mekoprint can both develop and produce, because they then must produce what they themselves propose in the development process.

Chief Technology Officer, Bioservo

Ola Markusson

The challenge: wearable HMI with bendable circuitry

In addition to controls accessible via a mobile phone, the glove also required the integration of a physical keypad mounted on the wrist. Therefore, this keypad had to be:

bendable, placing special demands on the circuitry
comfortable to wear, limiting its size
intuitive to use, with a specific focus on light diffusion
water-tight, requiring special sealing of the gasket
stitched onto the glove, putting pressure on the design

Our task was to combine and engineer the right "keypad building blocks" that would meet all requirements within budget and time,

"They [Mekoprint] are ambitious and proactive and come up with good suggestions to make the product even better."

Chief Technology Officer, Bioservo

Ola Markusson

Our Approach: Structured HMI development

To find a solution that has never been tested before, we employed our deep HMI know-how and a natural curiosity. We innovated together with our customer, in a documented, constructive and structured way. This has been an iterative process: prototyping a concept, testing it, and then fine-tuning various elements to achieve the right balance among all requirements.

Outcome: An HMI assembly

Our development process included a long list of deliverables along the way, including a rigid-flex circuitry development, button layout, test specification and design. The final product is an HMI assembly consisting of a silicone rubber keypad, a rigid-flex circuit, and a long flexible wire assembly, able to withstand pull.

Photo credit: Bioservo

Complete HMI solution with silicone rubber keypad, PCB and cables

Photo credit: Bioservo

"We expected a lot from Mekoprint. The circuits had to be able to bend. The product had to be easy to operate, not take up too much space, and look good. It is difficult, but Mekoprint has managed to solve the challenges."

Industrial Designer, Bioservo

Emma Linder