A device to control strength of interactions between adjacent nanostructures, namely Precise Interaction Control System for Nanostructures (PICSN) is developed. The PICSN is operated by combinations of DC motor and capacitancepositioning sensor. In this system, nanostructures are deposited on a flexible substrate and the strength of interactions can be controlled by changing a distance between adjacent nanostructures, stretching or shrinking the flexible substrate. Using the PICSN, we investigate photoluminescence of Au nanoclusters (NCs), which include at least Au5, Au8 and Au13 NCs, deposited on poly(dimethylsiloxane) substrate. We observed a blue shift of PL peak position with increasing interdot distance. Considering the relationship between absorption and emission energies of Au NCs, the blue shift is thought to be a result of fluorescent resonant energy transfer from smaller sized Au NCs to larger ones.