The components are stored in the backpack, which can also be used to carry the user’s belongings (photo: press)

Published on 04/28/2025

By Maria Fernanda Ziegler  |  Agência FAPESP – Researchers from the São Paulo State University (UNESP) and the Federal University of Espírito Santo (UFES) in Brazil have developed a wearable device to help visually impaired people move around. The technology has tactile beacons that can warn of the presence of obstacles, guaranteeing users greater autonomy and safety when walking.

Integrated into a backpack, the system consists of a camera with an RGB depth sensor – which captures images in a way very similar to the human visual experience – and an image processing unit with various components, including a Jetson Nano processor. The minicomputer is suitable for tasks such as image classification, object detection, segmentation and speech processing. The details of the research were described in the journal Disability and Rehabilitation: Assistive Technology.

“The components are stored in the backpack, which can also be used to carry the user’s belongings. The wires run inside the backpack and the straps, which vibrate when the user approaches an obstacle. If it’s on the left, the left side vibrates. If it’s on the right, the right vibrates. And if it’s in front, both vibrate,” says Aline Darc Piculo dos Santos, currently a professor at the School of Architecture, Urbanism and Design of the University of São Paulo (FAU-USP) and first author of the article.

The device was developed during Santos’ doctoral studies at the Faculty of Architecture, Arts and Communication (FAAC) at UNESP’s Bauru campus. The work was supported by FAPESP, the National Council for Scientific and Technological Development (CNPq) and the Espírito Santo Research Foundation (FAPES).

The researcher says she chose to use tactile feedback instead of an audible warning because auditory information plays an important role in the orientation and mobility process for visually impaired people.

“Our main objective was, based on wearable technology, to increase obstacle detection, because with a cane you can only map what’s below the waistline. So the idea isn’t to replace the cane – a device the user is already used to and is unlikely to stop using – but for it to complement the backpack,” she explains.

The development of the prototype, called NavWear, involved an interdisciplinary team of designers and electrical engineers, taking into account not only functionality but also aspects such as comfort, device interaction with the user and ease of use.

“In addition to a major review of studies on mobility for visually impaired people and research on assistive technologies available for this public, we also partnered with a blind institution to understand user needs. Most devices of this type only address functional aspects. Few studies deal with aspects related to the interaction between the user and the device, which can influence acceptance and satisfaction with the product,” says the researcher.

Preliminary study

To arrive at the model described in the article, the researchers conducted a study with 11 visually impaired adults and a health professional specializing in orientation and mobility.

“In this preliminary study, visually impaired people expressed a high level of concern about their safety in external and unfamiliar environments, as well as difficulty in identifying obstacles not detected by the common cane,” says Santos.

The researcher says that the prototype was evaluated from two perspectives: usability of the device and observers’ perception of the user. The first evaluation was carried out in a controlled environment that simulated tasks such as blindfolded walking. “In this testing stage, it was possible to observe that the combined use of the technologies resulted in fewer collisions. Participants also reported feeling more secure and that it was less difficult to complete the route,” she emphasizes.

According to the researcher, one limitation of the study was the inability to test the prototype on blind people. “Since it was developed during the social isolation period of the COVID-19 pandemic, there was this limitation. Although the results cannot be generalized to visually impaired users, as they may have a different interaction, they’re promising and highlight the device’s potential for outdoor use,” she says.

The article “NavWear: design and evaluation of a wearable device for obstacle detection for blind and visually impaired people” can be read at: www.tandfonline.com/doi/full/10.1080/17483107.2025.2477681.

 

Source: https://agencia.fapesp.br/54589