  We investigate warm inflationary scenario in which the accelerated expansion
of the early Universe is driven by chameleon-like scalar fields. Due to the
non-minimal coupling between the scalar field and the matter sector, the
energy-momentum tensor of each fluid component is not conserved anymore, and
the generalized balance equation is obtained. The new source term in the energy
equation can be used to model warm inflation. On the other hand, if the
coupling function varies slowly, the model reduces to the standard model used
for the description of cold inflation. To test the validity of the warm
chameleon inflation model, the results for warm inflationary scenarios are
compared with the observational Planck2018 Cosmic Microwave Background data. In
this regard, the perturbation parameters such as the amplitude of scalar
perturbations, the scalar spectral index and the tensor-to-scalar ratio are
derived at the horizon crossing in two approximations, corresponding to the
weak and strong dissipative regimes. As a general result it turns out that the
theoretical predictions of the chameleon warm inflationary scenario are
consistent with the Planck 2018 observations.
