File size: 8,428 Bytes
32502a8
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
"""Train the stable human-motion-to-Microduck-command policy used by the show."""

from __future__ import annotations

import argparse
import csv
import json
from pathlib import Path
import random
import time

import numpy as np
import onnx
import torch
from torch import nn
from torch.utils.data import DataLoader, TensorDataset


class CommandPolicy(nn.Module):
    def __init__(
        self,
        input_dim: int,
        feature_mean: torch.Tensor,
        feature_std: torch.Tensor,
        command_mean: torch.Tensor,
        command_std: torch.Tensor,
    ) -> None:
        super().__init__()
        self.register_buffer("feature_mean", feature_mean)
        self.register_buffer("feature_std", feature_std)
        self.register_buffer("command_mean", command_mean)
        self.register_buffer("command_std", command_std)
        self.net = nn.Sequential(
            nn.Linear(input_dim, 128),
            nn.ELU(),
            nn.Linear(128, 128),
            nn.ELU(),
            nn.Linear(128, 64),
            nn.ELU(),
            nn.Linear(64, 13),
        )

    def forward(self, features: torch.Tensor) -> torch.Tensor:
        normalized = (features - self.feature_mean) / self.feature_std
        return self.net(normalized) * self.command_std + self.command_mean

    def normalized_command(self, features: torch.Tensor) -> torch.Tensor:
        normalized = (features - self.feature_mean) / self.feature_std
        return self.net(normalized)


def run(args: argparse.Namespace) -> dict:
    random.seed(args.seed)
    np.random.seed(args.seed)
    torch.manual_seed(args.seed)
    started = time.time()
    source = np.load(args.retarget.resolve(), allow_pickle=True)
    features = source["human_features_14d"].astype(np.float32)
    targets = source["command_13d"].astype(np.float32)
    names = [str(value) for value in source["human_feature_names"]]
    val_mask = np.arange(len(features)) % 5 == 0
    train_mask = ~val_mask
    x_train, y_train = features[train_mask], targets[train_mask]
    x_val, y_val = features[val_mask], targets[val_mask]

    feature_mean_np = x_train.mean(axis=0)
    feature_std_np = np.maximum(x_train.std(axis=0), 1e-4)
    command_mean_np = y_train.mean(axis=0)
    command_std_np = np.maximum(y_train.std(axis=0), 1e-4)
    feature_mean = torch.tensor(feature_mean_np)
    feature_std = torch.tensor(feature_std_np)
    command_mean = torch.tensor(command_mean_np)
    command_std = torch.tensor(command_std_np)
    input_dim = features.shape[1]
    model = CommandPolicy(input_dim, feature_mean, feature_std, command_mean, command_std)
    train_y_normalized = (y_train - command_mean_np) / command_std_np
    loader = DataLoader(
        TensorDataset(torch.tensor(x_train), torch.tensor(train_y_normalized)),
        batch_size=args.batch_size,
        shuffle=True,
        generator=torch.Generator().manual_seed(args.seed),
    )
    optimizer = torch.optim.AdamW(model.parameters(), lr=args.learning_rate, weight_decay=1e-6)
    scheduler = torch.optim.lr_scheduler.CosineAnnealingLR(optimizer, T_max=args.epochs)
    noise_std = torch.tensor(
        [0.001, 0.001, 0.005, 0.005, 0.005, 0.015, 0.015, 0.01, 0.01, 0.005, 0.005, 0.0, 0.0, 0.0]
    )
    loss_fn = nn.SmoothL1Loss(beta=0.08)
    x_val_t = torch.tensor(x_val)
    y_val_t = torch.tensor(y_val)
    rows: list[dict] = []
    best_rmse = float("inf")
    best_state = None

    for epoch in range(1, args.epochs + 1):
        model.train()
        total = 0.0
        count = 0
        for batch_x, batch_y in loader:
            augmented = batch_x + torch.randn_like(batch_x) * noise_std
            predicted = model.normalized_command(augmented)
            loss = loss_fn(predicted, batch_y)
            optimizer.zero_grad(set_to_none=True)
            loss.backward()
            torch.nn.utils.clip_grad_norm_(model.parameters(), 1.0)
            optimizer.step()
            total += float(loss.detach()) * len(batch_x)
            count += len(batch_x)
        scheduler.step()
        model.eval()
        with torch.no_grad():
            predicted = model(x_val_t)
            rmse = torch.sqrt(torch.mean((predicted - y_val_t) ** 2))
            mae = torch.mean(torch.abs(predicted - y_val_t))
        row = {
            "epoch": epoch,
            "train_smooth_l1": total / max(1, count),
            "val_rmse_command": float(rmse),
            "val_mae_command": float(mae),
            "learning_rate": optimizer.param_groups[0]["lr"],
        }
        rows.append(row)
        if row["val_rmse_command"] < best_rmse:
            best_rmse = row["val_rmse_command"]
            best_state = {
                key: value.detach().cpu().clone()
                for key, value in model.state_dict().items()
            }
        if epoch == 1 or epoch % 50 == 0 or epoch == args.epochs:
            print(json.dumps(row))

    assert best_state is not None
    model.load_state_dict(best_state)
    model.eval()
    output = args.output.resolve()
    output.mkdir(parents=True, exist_ok=True)
    torch.save({
        "state_dict": best_state,
        "seed": args.seed,
        "feature_names": names,
        "architecture": [input_dim, 128, 128, 64, 13],
    }, output / "human_motion_command_policy.pt")
    with (output / "training_metrics.csv").open("w", newline="", encoding="utf-8") as stream:
        writer = csv.DictWriter(stream, fieldnames=rows[0].keys())
        writer.writeheader()
        writer.writerows(rows)
    np.savez_compressed(
        output / "normalization.npz",
        feature_mean=feature_mean_np,
        feature_std=feature_std_np,
        command_mean=command_mean_np,
        command_std=command_std_np,
        feature_names=np.asarray(names),
    )

    onnx_path = output / "human_motion_command_policy.onnx"
    torch.onnx.export(
        model,
        torch.zeros((1, input_dim), dtype=torch.float32),
        str(onnx_path),
        input_names=["human_motion_features"],
        output_names=["microduck_command_13d"],
        dynamic_axes={
            "human_motion_features": {0: "batch"},
            "microduck_command_13d": {0: "batch"},
        },
        opset_version=17,
        dynamo=False,
    )
    graph = onnx.load(str(onnx_path))
    for key, value in {
        "input_features": ",".join(names),
        "output_contract": "twist(3),head_pose(4),body_pose(6)",
        "control_hz": "50",
        "target_bpm": "111",
        "low_level_controller": "official Pollen Microduck policy family",
    }.items():
        item = graph.metadata_props.add()
        item.key = key
        item.value = value
    onnx.save(graph, str(onnx_path))
    with torch.no_grad():
        full_pred = model(torch.tensor(features)).numpy()
    error = full_pred - targets
    summary = {
        "schema_version": "1.0",
        "training_method": "supervised human-motion feature to deployable command policy",
        "seed": args.seed,
        "epochs": args.epochs,
        "frames": len(features),
        "best_validation_rmse_command": best_rmse,
        "full_sequence_rmse_command": float(np.sqrt(np.mean(error ** 2))),
        "max_abs_command_error": np.max(np.abs(error), axis=0).round(7).tolist(),
        "elapsed_seconds": time.time() - started,
        "input_features": names,
        "output_contract": "[twist(3), head_pose(4), body_pose(6)]",
        "safety_architecture": "learned choreography command policy + official Pollen balancing policies",
        "files": {
            "checkpoint": "human_motion_command_policy.pt",
            "onnx": "human_motion_command_policy.onnx",
            "metrics": "training_metrics.csv",
            "normalization": "normalization.npz",
        },
    }
    (output / "training_summary.json").write_text(
        json.dumps(summary, indent=2),
        encoding="utf-8",
    )
    print(json.dumps(summary, indent=2))
    return summary


def main() -> None:
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument("--retarget", type=Path, required=True)
    parser.add_argument("--output", type=Path, required=True)
    parser.add_argument("--epochs", type=int, default=500)
    parser.add_argument("--batch-size", type=int, default=256)
    parser.add_argument("--learning-rate", type=float, default=1e-3)
    parser.add_argument("--seed", type=int, default=20260830)
    run(parser.parse_args())


if __name__ == "__main__":
    main()