New Apps Enable Safer Indoor Navigation for Blind People

A blind navigator tests an indoor navigation app in the halls of the Baskin Engineering building.

Two new smartphone apps in development aim to help blind people navigate indoor spaces with spoken directions, addressing the challenge of wayfinding in environments where GPS doesn’t work. UC Santa Cruz professor of Computer Science and Engineering, Roberto Manduchi, an expert in accessible technology, has focused on developing tools for indoor navigation to assist the blind and visually impaired. Manduchi’s research group presented two smartphone apps in the journal ACM Transactions on Accessible Computing that “provide indoor wayfinding, navigation to a specific point, and safe return, the process of tracing back a past route.”

“Moving around independently in unfamiliar places is especially difficult without visual references,” Manduchi explains. His team has developed two apps that offer indoor navigation and safe return capabilities, providing audio cues without the need for users to hold out their phones, which can be inconvenient and risky as one hand is always required for a guide dog or a cane to navigate.

Unlike existing systems that require costly infrastructure like indoor sensors, Manduchi’s apps use smartphones' built-in sensors, such as accelerometers and gyros, to track movement and orientation, making it much more accessible. Particle filtering is also applied to correct for errors, ensuring users don’t appear to walk through walls or other obstacles. The apps work similarly to GPS navigation but without the need for a satellite signal, which is often blocked indoors.

Students in Professor Roberto Manduchi's lab help set up the indoor navigation app so it can be tested with a blind navigator.

The backtracking app is particularly useful for helping users retrace their steps, while a magnetometer assists in detecting magnetic anomalies that can act as landmarks in a building. Both apps provide spoken directions and can be paired with a smartwatch for additional cues through vibrations.

Manduchi’s team tested the system successfully in the UC Santa Cruz Baskin Engineering hallways and plans to add AI features for scene descriptions and improved map access to give users more context to their surroundings. He credits the local blind community for their invaluable feedback, emphasizing the importance of starting from the user’s needs when designing technology for accessibility.