Pre-trained model conversion to tensorrt format from etlt using tlt-converter on Orin NX

You can refer to TAO Converter | NVIDIA NGC and download v4.0.0_trt8.5.2.2_aarch64 version for your case.

wget --content-disposition 'https://api.ngc.nvidia.com/v2/resources/org/nvidia/team/tao/tao-converter/v4.0.0_trt8.5.2.2_aarch64/files?redirect=true&path=tao-converter' -O tao-converter

You can also decode the .etlt model to .onnx file(refer to Fpenet retraining output file onnx but deepstream is using tlt - #12 by Morganh) and then use trtexec to generate tensorrt engine. Refer to TRTEXEC with YOLO_v4_tiny - NVIDIA Docs.