The Augmented Listening Laboratory at the University of Illinois Urbana-Champaign has developed 3D-printed, humanoid robot heads that can talk and listen to each other. The team hopes to use these realistic talking heads to investigate how humans receive sound and develop audio technology.
The Talking Human Head Simulators
The talking human head simulators were designed to help algorithms used to improve human hearing by considering the acoustic properties of the human head. Hearing aids, for example, adjust sound received at each ear to create a more realistic listening experience. For the adjustment to succeed, an algorithm must realistically assess the difference between the arrival time at each ear and amplitude of the sound.
The researchers hope to study human listening in natural environments, such as cocktail parties, where many conversations occur at once. However, simulating realistic scenarios for conversation enhancement often requires hours of recording with human subjects. The entire process can be exhausting for the subjects, and it is extremely hard for a subject to remain perfectly still in between and during recordings, which affects the measured acoustic pressures. Acoustic head simulators can overcome both drawbacks. They can be used to create large data sets with continuous recording and are guaranteed to remain still.
In a feat of design and engineering, the heads are 3D-printed into components and assembled, enabling customization at low cost. The highly detailed ears are fitted with microphones along different parts to simulate both human hearing and Bluetooth earpieces. The “talkbox,” or mouthlike loudspeaker, closely mimics human vocals.
To facilitate motion, the researchers paid special attention to the neck. Because the 3D model of the head design is open source, other teams can download and modify it as needed. The diminishing cost of 3D printing means there is a relatively low barrier for fabricating these heads.
The Augmented Listening Laboratory has also created wheeled and pulley-driven systems to simulate walking and more complex motion. The researchers hope that the 3D-printed talking robot heads will be used in the future to simulate realistic scenarios for conversation enhancement, leading to the development of better audio technology.