The primary challenge in robotics AI is the lack of real-world training data. To solve this, models are bootstrapped using a combination of learning from human lifestyle videos and extensive simulation environments. This creates a foundational model capable of initial deployment, which then generates a real-world data flywheel.

In robotics, purely imitating human actions is insufficient. A model trained this way doesn't learn how to recover from inevitable errors. Comma AI solves this by training its models in a simulator where they are forced to learn recovery paths from off-course situations, a critical step for real-world deployment.

Unlike cars, which gather data passively, humanoid robots need active training. To solve this, Musk's strategy is to build a physical 'academy' of 10,000-30,000 Optimus robots performing self-play on various tasks, using this real-world data to close the 'sim-to-real' gap from millions of simulated robots.

A major hurdle in robotics is the laborious collection of real-world training data. Atlas accelerates this by creating high-fidelity simulations from sparse real-world images ("real-to-sim"), enabling rapid training and randomization of robotic policies without extensive data capture.

Generalist CEO Pete Florence provides a tier list for robotics training data. He ranks "lived experience of the physical world" as S-tier, emphasizing the irreplaceable value of high-quality, real-world data. In contrast, he rates synthetic data from world models as F-tier, suggesting it is far less effective.

Instead of simulating photorealistic worlds, robotics firm Flexion trains its models on simplified, abstract representations. For example, it uses perception models like Segment Anything to 'paint' a door red and its handle green. By training on this simplified abstraction, the robot learns the core task (opening doors) in a way that generalizes across all real-world doors, bypassing the need for perfect simulation.

A common misconception is that simulation perfectly represents reality. In practice, it's a continuous loop: real-world data is required to tune simulator parameters, and this validation must be repeated until the gap between simulation and reality is small enough to trust the results.

Instead of using traditional, rule-based simulators, Comma AI trains its driving agent inside a learned "world model." This generative model creates photorealistic, diverse driving scenarios and, crucially, responds accurately to the agent's simulated actions—a key requirement for effective robotics training.

Creating realistic training environments isn't blocked by technical complexity—you can simulate anything a computer can run. The real bottleneck is the financial and computational cost of the simulator. The key skill is strategically mocking parts of the system to make training economically viable.