All of the potential applications of humanoid robots, which I have broadly divided into the robot workplace assistant or the robot companion, have one thing in common: dose interaction between human and robot. The nature of that interaction will be characterized by close proximity and communication via natural human interfaces—speech, gesture, and body language. Human and robot may or may not need to come into physical contact, but even when direct contact is not required they will still need to be within each other’s body space. It follows that robot safety; dependability, and trustworthiness are major issues for the robot designer. But given that we humans are unpredictable, then how can we design and build human robots to be safe in all circumstances?
Robots, like any machine that is tasked or entrusted with a particular job, need to be designed to be safe and reliable. This is the same level of dependability we would expect from our car or washing machine, i.e. that it’s been well designed, and built to meet or exceed standards of manufacture and product safety. But making a robot safe isn’t the same as making it trustworthy. One person trusts another if, generally speaking, that person is reliable and does what they say they will. So if I were to provide a robot that helps to look after your grandmother and I claim that it is perfectly safe—that it’s been designed to cover every risk or hazard—would you trust it? The answer is probably not.
Trust in robots, just as in humans, has to be earned. First you would like to see the robot in action (preferably not with your grandmother). Perhaps you would like to interact with it yourself; in so doing you build a mental model of how the robot behaves and reacts and, over time, if those actions and reactions are consistent and predictable for the circumstances, then you will build a level of trust for the robot The important thing here is that trustworthiness cannot just be designed into the robot—it has to be earned by use and by experience. Consider a robot intended to fetch drinks for an elderly person. Imagine that the person calls for a glass of water. The robot then needs to fetch the drink, which may well require the robot to find a glass and fill it with water. Those tasks require sensing, dexterity; and physical manipulation, but they are problems that can be solved with current technology.
Robotics
Automation Examples
The problem of trust arises when the robot brings the glass of water to the human. How does the robot give the glass to the human? If the robot has an arm so that it can hold out the glass in the same way a human would, how would the robot know when to let go? The robot clearly needs sensors in order to see and feel when the human has taken hold of the glass. The physical process of a robot handing something to a person is fraught with difficulty; Imagine, for instance, that the robot holds out its arm with the glass but the human can’t reach the glass. How does the robot decide where and how far it would be safe to bring its arm toward the person? What if the human takes hold of the glass but then the glass slips; does the robot let it fall or should it—as a human would—renew its grip on the glass? At what point would the robot decide the transaction has failed: it can’t give the glass of water to the person, or they won’t take it; perhaps they are asleep, or simply forgotten they wanted a glass of water, or confused. How does the robot sense that it should give up and perhaps call for assistance? These are difficult problems in robot cognition. Until they are solved, it’s doubtful we could trust a robot sufficiently well to do even a seemingly simple thing like handing over a glass of water. So how might we begin to consider designing a robot that would be trusted with this kind of task?
Industrial Robotics
From a technical point of view, the robot needs two control systems: one is the cognitive system that actually carries out the task. Another, parallel, safety system is one that would constantly check for unexpected faults or hazards. The primary job of the safety protection system is to stop the robot, but in a safe fashion (noting that there are some situations where freezing the robot would itself be an unsafe thing to do). First we must solve the problems of cognition and safety. Next a robot must prove itself dependable in use. Only then is it likely to earn our trust.