Physical human-robot interaction (pHRI) enables to achieve various assistive tasks for people by robots such as collaborative robotics or motion assistance. It pertains both planning-control and hardware considerations. We propose a new soft robot skin that can detect human contact through thermal features. An electrically conductive pipe is interposed between graphite sheet that has high heat conductivity and softmaterial for cover compliance. Then the temperature of the water pipe is controlled by a heat source and a small water pump .  Besides, an observer for estimating heat flow is implemented; it can detect human interaction by measuring the temperature change of the water pipe. Hence, there is no need to attach sensors to the robot skin's surface , which can be kept soft and eventually textured with a desired pattern . We assessed the validity of the prototype in experiments of  contact detection by human fingers .
 We propose a new robotic cover prototype that achieves thermal display while also being soft . We focus on the thermal cue because previous human studies have identified it as part of the touch pleasantness. The robotic cover surface can be regulated to the desired temperature by circulating water through a thermally conductive pipe embedded in the cover, of which temperature is controlled. Besides, an observer for estimating heat from human contact is implemented; it can detect human interaction while displaying the desired temperature without temperature sensing on the surface directly . We assessed the validity of the prototype in experiments of temperature control and contact detection by human hand .
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Physical human-robot interaction (pHRI) enables to achieve various assistive tasks for people by robots such as collaborative robotics or motion assistance. It pertains both planning-control and hardware considerations.
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soft robot skin that can detect human contact through thermal features. An electrically conductive pipe is interposed between graphite sheet that has high heat conductivity and softmaterial for cover compliance. Then the temperature of the water pipe is controlled by a heat source and a small water pump
robotic cover prototype that achieves thermal display while also being soft
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We focus on the thermal cue because previous human studies have identified it as part of the touch pleasantness. The robotic cover surface can be regulated to the desired temperature by circulating water through a thermally conductive pipe embedded in the cover, of which temperature is controlled.
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flow
from human contact
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by measuring the temperature change of the water pipe. Hence, there is no need to attach sensors to the robot skin's surface , which can be kept soft and eventually textured with a desired pattern
while displaying the desired temperature without temperature sensing on the surface directly
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temperature control and
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fingers
hand