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The rubber hand illusion (RHI) is a remarkable perceptual illusion affecting the experience of one's own body. However, methodological differences between studies are very common, which affects comparability across studies. This leads to inconsistent, sometimes contradictory, results and interpretations. One source of methodological differences is in the stimulation protocol of the illusion. Here we describe a simple and affordable device that automates the stimulation procedure in a typical rubber hand illusion setup. This device delivers tactile stimulation to the participant's real hand and the model hand. It allows variation of the frequency and delay between the two touches (i.e., asynchronous stimulation), some of most common parameters in the stimulation protocol of RHI studies. We present the results of a validation study, in which we compare it against the classical manual stimulation procedure. Crucially we show that the automated procedure leads to illusory experiences as expected with high illusion ratings during synchronous, but not asynchronous stimulation. Further, this procedure displays similar illusion strength and number of illusion responders as the manual procedure. These results suggest that automated induction is a viable alternative to manual induction with the advantage of precise control and description. Adopting an automated procedure will increase reliability and replicability for rubber hand illusion studies.

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