Typically, spacecraft development is costly and time-consuming because of the many iterations usually needed to reach optimal design solutions. This paper presents an innovative approach that eliminates the need to iterate the thermal design process using a network of variable conductance oscillating heat pipes (VC-OHPs) on every structural panel. The temperatures of the panels where components are mounted would thus be maintained at constant levels by VC-OHPs, even if the instruments' locations or heat dissipation changes. A structural thermal model was built to verify the proposed thermal and structural design in a simulated deep space environment and in a launch environment. It consisted of two VC-OHPs and six aluminum honeycomb panels. A thermal vacuum test was conducted to demonstrate the temperature control by the VC-OHPs. The test results showed that temperature control by VC-OHPs could maintain the panels operating as evaporators at stable temperatures and follow the reservoir temperature. A vibration test was conducted under the launch environment of a Japanese H2A rocket. The results confirmed that the structural thermal model met requirements for resistance to mechanical launch environment. The VC-OHPs functioned after the vibration test. The structural thermal model showed that the proposed thermal control architecture is feasible in an actual spacecraft in terms of thermal and structure design.