New workshop paper: What Are We Measuring? Bonding, Trust, and Human–Robot Relationships

I’m pleased to share that I’ve had a workshop paper accepted at the Human State-Aware Robotics (H-STAR): From Multimodal Data to Human-Adaptive Behavior in HRI workshop at RO-MAN 2026 in Kitakyushu, Japan.

The paper, What Are We Measuring? Bonding, Trust, and the Evaluation of Human–Robot Relationships, takes aim at a habit that has quietly become standard in HRI: using trust, usually captured with a self-report questionnaire, as a stand-in for the quality of a human–robot relationship as a whole.

In this short paper, I argue this is a category error. Trust is a cognitive appraisal of whether a robot will perform reliably: forward-looking, quick to update, and fragile, such that a single salient failure can undo it. Social bonding is something else i.e. an affiliative social connection that accumulates slowly through repeated interaction, and shows up in largely involuntary, bodily (physiological and biobehavioural) signals. Trust and bonding can track, and they often do, but they can also come apart.

So, when we treat bond and trust as two independent dimensions rather than one, we get a 2D space of relationship states, which I simply call the bond × trust space. The paper breaks this space down into four “regions” of relationship types, where low bond and low trust = avoidance, low bond and high trust = functional, high bond and low trust = dependence , and high bond, high trust = symbiosis. I discuss some of the practical and ethical considerations of thinking about bonding and trust in this way, and look forward to talking about it more at RO-MAN 2026.

This is part of a series of larger papers I’m currently working on, so I’d love to talk to anyone thinking about similar problems e.g. measurement, attachment, long-term deployments, or the ethics of bonding with robots and other artificial systems. Please do get in touch if any of this sounds interesting to you.