The process of 4D printing of composites (4DPC) can make curved laminates without the need for curved molds. This is due to the use of unsymmetric laminates. Stacks of laminates with specified layup sequence (for thin composite laminates) are deposited on to flat molds using an automated fiber placement machine (AFP). On curing, the laminate takes a curved shape which can be determined by laminate theory. The factors that contribute to the curvature of the samples are the difference in coefficients of thermal contraction and shrinkage of the resin during curing.
When a thin composite laminate made by 4DPC is placed in room conditions, it is observed to open up and changes its radius of curvature over time. This is due to the absorption of moisture from the surroundings through diffusion. 
This research aims to find the effect of the contribution of temperature, resin shrinkage and moisture absorption on the radius of curvature of the samples. 
To analyze the contribution of difference in coefficients of thermal contraction and resin shrinkage on the curvature of the samples, the samples were first completely desorbed of moisture by desorption test and then a temperature cycling test is carried out. The results obtained from temperature cycling test are compared with the theoretical results generated using the MATLAB program. To study the effect of moisture on the thin composite samples, moisture absorption tests were performed to determine the change in radius and weight of samples over the course of time.