
In today’s era, when robots are increasingly entering our workspaces and homes, their interactions with humans must be natural and meaningful. Traditional robotics often prioritizes function—optimizing movements for efficiency and precision, making them more mechanical. To address this, researchers from Apple have introduced a new framework -ELEGNT: Expressive and Functional Movement Design for Non-anthropomorphic Robots. It combines functional and expressive movement to enable non-humanoid robots to communicate their emotions, intentions, and attitudes to engage with humans.
What is the ELEGNT Framework?
The ELEGNT framework, developed by Apple researchers, allows robots to perform tasks effectively while expressing their internal states through motions such as nodding to show agreement and tilting to indicate curiosity. These features can significantly improve user experience and engagement with robots.
In a demonstration video shared by Apple, a lamp-like prototype robot could follow commands, nod in agreement, and complete tasks such as highlighting the spots based on the user’s hand gestures.
Apple researchers documented the process in a research paper published in the online pre-print journal arXiv. Let’s understand the process behind the research.
The Core Idea: Blending Function and Expression:
The core idea behind the ELEGNT framework is that adding features in robots, such as expressing their internal states and communicating through dynamic movements, can significantly enhance user engagement and trust. Based on this, the team has developed a robotic lamp that can move up to six degrees of freedom, along with functional capabilities such as providing light and projecting images, as well as, expressions such as dynamic motion and gazing. The goal was to balance task efficiency with the capability to express and convey intentions.
Designing Expressive Robots:
The Researchers used principles of animation, behavioral science, and human kinesics to design the lamp-like robot’s movements. Robotic movements are crafted on four expressive behaviors -Intention, Attention, Attitude, and Emotion. By incorporating these features the robot’s motion becomes more engaging and relatable in social settings.
- Intention: Includes movements that indicate the robot’s next action, such as looking at a target before proceeding toward it.
- Attention: Gaze-like behaviors using light and motion to indicate focus area.
- Attitude: Gestures that convey agreement, hesitation, or confidence, such as nodding or pausing.
- Emotion: Movements that imitate human-like expressions, such as bouncing to show excitement or lowering the head to indicate sadness.
User Study: Do Expressive Robots Improve Engagement?
A user study was conducted with 21 participants to assess the expressive lamp-like robots’ effectiveness, where the robots were observed in six scenarios such as playing music, adjusting lighting, providing reminders, indicating failure, social interaction providing assistance.
Each scenario was compared with two variations of robots- one using only function-driven movements and another integrating expression-driven behaviors. The researchers got remarkable results in this study.
Key Findings: Expression-Driven vs. Function-Driven Robots
Robots that exhibited expressive movements received significantly higher ratings for user engagement, intelligence, and human likeness. Participants also reported feeling a stronger connection with these robots, especially during tasks like playing music or having social conversations. In contrast, participants described purely functional robots as emotionless and boring.
Interestingly, the context of the task affected user preferences. Expressive behaviors were rated high in social settings where engagement plays a significant role. However, some participants found that expressive movements are unnecessary or distracting for function-oriented tasks, such as adjusting lighting.
Challenges and Opportunities:
The study revealed that while expressive movements of the robot significantly enhance interaction quality, aligning these motions with other robot modalities, such as voice and light, will significantly enhance the user experience. Mismatches—like a robot’s speech cadence not aligning with its gestures—can disrupt the user interaction with the robot. Additionally, the study noted that excessive or poorly timed movements might annoy users or hinder task efficiency.
Future research will likely focus on personalizing robot behaviors to individual user preferences. For example, while some users enjoy playful and animated robots, others may prefer minimalistic designs that prioritize functionality.
Implications for Human-Robot Interaction:
Apple’s ELEGNT framework demonstrates how the expressive movements of robots can transform them from mere tools into engaging companions. By integrating functional efficiency with emotional connection, there is a huge opportunity for Human-Robot collaboration. This approach has the potential to revolutionize how we interact with non-anthropomorphic robots. Whether assisting in daily tasks or providing companionship, robots designed with expressive and functional balance could become more intuitive, trustworthy, and enjoyable parts of our lives.
The Future of Expressive Robotics:
As robots continue to integrate into human environments, frameworks like ELEGNT offer a roadmap for designing machines that not only work but also connect on a deeper level. The future of robotics isn’t just about what robots can do—it’s about how they make us feel.