Methods and apparatus for operation and navigation of agents in global positioning system (GPS) denied environments

An apparatus, comprising:

• a processor;
• and
• a memory coupled to the processor, the memory storing a machine learning model, a multimodal model and a fine-tuning module,
• the machine learning model configured to receive at least one input image, the machine learning model configured to output a first location pair associated with the at least one input image and a first location indication of the apparatus,
• the multimodal model configured to receive the first location pair from the machine learning model, the at least one input image, and sensor data from at least one sensor, the multimodal model configured to output a second location pair associated with a second location indication of the apparatus, and
• the fine-tuning module configured to receive the first location pair from the machine learning model and the second location pair from the multimodal model, the fine-tuning module configured to output a third location pair associated with a third location indication of the apparatus based on the first location pair and the second location pair, the third location pair having an accuracy greater than an accuracy of the first location pair and an accuracy of the second location pair.