Initial snapshot: hand motion pipeline (Dyn-HaMR + dex-retargeting + SPIDER)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

third_party/Dyn-HaMR/third-party/DROID-SLAM/droid_slam/modules/clipping.py

@@ -0,0 +1,24 @@
+import torch
+import torch.nn as nn
+import torch.nn.functional as F
+
+GRAD_CLIP = .01
+
+class GradClip(torch.autograd.Function):
+    @staticmethod
+    def forward(ctx, x):
+        return x
+
+    @staticmethod
+    def backward(ctx, grad_x):
+        o = torch.zeros_like(grad_x)
+        grad_x = torch.where(grad_x.abs()>GRAD_CLIP, o, grad_x)
+        grad_x = torch.where(torch.isnan(grad_x), o, grad_x)
+        return grad_x
+
+class GradientClip(nn.Module):
+    def __init__(self):
+        super(GradientClip, self).__init__()
+
+    def forward(self, x):
+        return GradClip.apply(x)