Physical AI from scratch
From one neuron to world action models, one interactive class at a time.
55 classes · 8 modules · 1 openM1Neurons and learning
- 01One neuron, by hand: weights, bias, step vs sigmoid, binary cross-entropy, one gradient step by the chain rule, and why one neuron can't learn XOROpen
- 02Hidden layers and backpropagation: an MLP learns XOR; gradient descent on the loss landscape and the learning-rate limitSoon
- 03Derivatives as a graph: the chain rule on a computation graphSoon
- 04Backpropagation I: build a tiny autograd engine (micrograd style)Soon
- 05Backpropagation II: train a small MLP with your engineSoon
- 06Layers and hidden units: width, depth and universal approximationSoon
- 07Classification: softmax, cross-entropy, and digits on CPUSoon
M2The deep learning toolkit
- 08Tensors and PyTorch autograd: the same ideas, at scaleSoon
- 09Optimizers: SGD, momentum, Adam, learning-rate schedulesSoon
- 10Generalization: overfitting, regularization, dropout, normalizationSoon
- 11Convolutions: filters, receptive fields, a small CNNSoon
- 12Embeddings and sequences: tokens, positions, why RNNs struggledSoon
- 13Attention from scratch: queries, keys, valuesSoon
- 14The transformer block: build and train a tiny GPTSoon
- 15Training in practice: data loading, mixed precision, checkpoints, debugging on 6 GBSoon
M3Generative models
- 16Autoencoders and latent spacesSoon
- 17Variational autoencoders and the ELBOSoon
- 18Diffusion I: adding noise and learning to remove itSoon
- 19Diffusion II: train and sample a small DDPMSoon
- 20Flow matching: straight paths from noise to dataSoon
- 21Conditioning and classifier-free guidanceSoon
- 22Tokenizing images and video: patches (ViT) and discrete codes (VQ)Soon
M4Robots and data
- 23Robot crash course: frames, rotations, forward kinematics [L24, L25]Soon
- 24Jacobians and inverse kinematics [L26, L27]Soon
- 25Trajectories and control loops [L20, L28]Soon
- 26Cameras and depth for robots [L30, L31]Soon
- 27Teleoperation: leader and follower arms on the SO-101Soon
- 28LeRobot datasets: episodes, frames, recording your ownSoon
- 29Action representations: joints vs end effector, chunks, frames of referenceSoon
- 30Simulation and sim-to-real with orbesimSoon
M5Imitation learning and RL
- 31Behavior cloning and compounding error [L33]Soon
- 32ACT I: action chunking and the CVAESoon
- 33ACT II: train ACT on a LeRobot datasetSoon
- 34Diffusion PolicySoon
- 35Evaluating policies: rollouts, success rate, honest statisticsSoon
- 36RL foundations: MDPs, returns, value, policy gradients [L34]Soon
- 37PPO in orbesimSoon
- 38Mixing the two: RL fine-tuning of imitation policiesSoon
M6VLMs and VLAs
- 39Contrastive vision-language learning: CLIP and SigLIPSoon
- 40Vision-language models: vision encoder plus language modelSoon
- 41From VLM to VLA: actions as outputs [L35]Soon
- 42SmolVLA I: the architecture and the action expertSoon
- 43SmolVLA II: fine-tune on your own SO-101 dataSoon
- 44π0 and flow-matching action expertsSoon
- 45GR00T: a fast and a slow systemSoon
- 46Deploying a VLA: latency, async inference, the real armSoon
M7Video world models
- 47What is a world model: from World Models to DreamerSoon
- 48Video diffusion: latent video models (Wan and friends)Soon
- 49World foundation models: NVIDIA CosmosSoon
- 50Synthetic robot data from video models: DreamGenSoon
- 51Latent actions: learning actions from video (LAPA, Genie)Soon
- 52Evaluating world modelsSoon
M8World action models
- 53DreamZero: predicting video and actions togetherSoon
- 54Dream-1 dissectedSoon
- 55Capstone: train a tiny world action model end to endSoon