In this research work severe environment electronic packaging for mechatronic applications was developed. The control of intelligent cylinder electronics was designed on a rigid-flexible pc-board using surface-mounted technology and minimizing separate connections. The unit was placed inside the actuator structure considering the machine surrounding requirements. The reliability of the electronics was investigated experimentally using temperature cycling (-40°C...+85°C) and vibration tests. The results indicate the feasilibility of PCB-technology in very demanding applications. Component placement and detailed planning of the vibration isolation has become important. The knowledge was applied in the development of a commercial product: an intelligent paper roll clamp in a truck. The test results of electronics and the function in actual work indicate the similarity to theoretical calculations and the product is today commercially available. Also a short explanation of the space vibration design problem is given.