A system comprising an object; a computer device with a digital model containing a virtual object corresponding to the object; a position sensor for detecting the position of the object; and a communication means to transmit the position of the object to the computer device. The object is stretchable and the system is further provided with sensors for detecting the stretched condition of the object and with communication means to transmit said condition to the computer device. A system with actuators to modify the position and/or the stretched condition of the object and use of such systems for a collaborative complex problem-solving procedure in the context of urban planning.