During my time working at Nuro, I worked on an 8-person team to prepare the company’s R1 delivery robot to make its debut on public roads. After the “unmanned launch” in Scottsdale, we ran a trial of 100 grocery deliveries to residents in a small area of the city. In addition to the trial, we used the robot to conduct user testing, in which local volunteers were surveyed by a researcher during their experience interacting with the bot during their grocery delivery. This is what first got me thinking about robot HMI and User Experience.

Giving proper feedback to the user gives them confirmation about their actions. It makes them know that the product is working, and that they know how to use it. It prevents the user from making mistakes, and connects them to the thing they’re using. Short audio tones can’t communicate very complex ideas, but they are perfect for communicating very simple ones, such as warnings and positive feedback for button presses.

The audio

I set myself three main criteria for the sounds:

• They need to be congruent with the playful features of the bot’s exterior.

• They need to ‘go together’.

• They need to sound good on a wide range of possible speakers used in future versions of the robot.

I produced two sets of sounds. The first is a bit more playful, using higher pitch, shorter tones, and an ascending major fifth for positive feedback. The second set is more monotone, using more neutral sounding intervals. Everything is kept very mid-range heavy to accomodate a wide range of speakers. All of the sounds were created using a Korg MS-20 analog synthesizer.

The demos are arranged in a way that simulates a real user flow. The user enters the PIN incorrectly at first, then correctly, prompting the cargo doors to open. The user takes their grocery bags and presses a button to close the doors. The bot emits one last warning sound before closing the doors.

This was mainly a project for myself as I thought it would be a great a learning experience. The sounds were eventually provided to Nuro to aid in the design process for their next generation bot, but were never used in any iteration of their robots.