A system for contactless determination of one or more features of a coating with one or more layers , the system comprising a plurality of units having a determiner unit and a measurement unit (103; 303a) including an ingress-protected coating scanner , an ingress-protected vibration explorer and an optical arrangement ; wherein the ingress-protected coating scanner includes an ingress-protected transmitter configured to emit, in use, a scanning radiation and an ingress-protected receiver configured to sense, in use, an interaction radiation caused by interaction of the scanning radiation with the one or more layers of the coating ; wherein the ingress-protected vibration explorer includes an ingress-protected emitter configured to emit, in use, an exploration radiation and an ingress-protected sensor configured to sense, in use, a reflection radiation caused by reflection of the exploration radiation on the coating to detect a vibration of the coating depending on the sensed reflection radiation ; wherein the optical arrangement includes either at least one mirror configured to reflect, in use, the scanning radiation towards a common radiation direction with the exploration radiation and at least one mirror configured to reflect, in use, the interaction radiation towards the ingress-protected receiver , or at least one mirror configured to reflect, in use, the exploration radiation towards a common radiation direction with the scanning radiation and at least one mirror configured to reflect, in use, the reflection radiation towards the ingress-protected sensor ; and wherein the determiner unit is configured to determine the one or more features of the coating depending on the interaction radiation sensed by the ingress-protected coating scanner and the vibration detected by the ingress-protected vibration explorer . the ingress-protected coating scanner includes an ingress-protected transmitter configured to emit, in use, a scanning radiation and an ingress-protected receiver configured to sense, in use, an interaction radiation caused by interaction of the scanning radiation with the one or more layers of the coating ; wherein the ingress-protected vibration explorer includes an ingress-protected emitter configured to emit, in use, an exploration radiation and an ingress-protected sensor configured to sense, in use, a reflection radiation caused by reflection of the exploration radiation on the coating to detect a vibration of the coating depending on the sensed reflection radiation ; wherein the optical arrangement includes either at least one mirror configured to reflect, in use, the scanning radiation towards a common radiation direction with the exploration radiation and at least one mirror configured to reflect, in use, the interaction radiation towards the ingress-protected receiver , or at least one mirror configured to reflect, in use, the exploration radiation towards a common radiation direction with the scanning radiation and at least one mirror configured to reflect, in use, the reflection radiation towards the ingress-protected sensor ; and wherein the determiner unit is configured to determine the one or more features of the coating depending on the interaction radiation sensed by the ingress-protected coating scanner and the vibration detected by the ingress-protected vibration explorer . <EOS>