This paper presents a work in progress on the perception of the attributes of the shape of a resonant object. As part of the ecological approach to perception-assuming that a sound contains specific morphologies that convey perceptually relevant information responsible for its recognition, called invariants-the PRISM laboratory has developed an environmental sound synthesizer aiming to provide perceptual and intuitive controls for a non-expert user. Following a brief presentation of the di↵erent strategies for controlling the perceptual attributes of the object, we present an experiment conducted with calibrated sounds generated by a physically-informed synthesis model. This test focuses on the perception of the shape of the object, more particularly its width and thickness since these attributes, especially the thickness, have not been much studied in the literature from a perceptual point of view. The first results show that the perception of width is di cult for listeners, while the perception of thickness is much easier. This study allows us to validate the proposed control strategy. Further works are planned to better characterize the perceptual invariants relevant for shape perception.