diff --git a/src/BulletSoftBody/btDeformableBodySolver.cpp b/src/BulletSoftBody/btDeformableBodySolver.cpp
index 618bf7ed5..676df528d 100644
--- a/src/BulletSoftBody/btDeformableBodySolver.cpp
+++ b/src/BulletSoftBody/btDeformableBodySolver.cpp
@@ -376,8 +376,8 @@ void btDeformableBodySolver::predictDeformableMotion(btSoftBody* psb, btScalar d
     psb->updateBounds();
     
     /* Integrate            */
-    // do not allow particles to move more than 10% of the bounding box size
-    btScalar max_v = 0.1 * (psb->m_bounds[1]-psb->m_bounds[0]).norm() / dt;
+    // do not allow particles to move more than the bounding box size
+    btScalar max_v = (psb->m_bounds[1]-psb->m_bounds[0]).norm() / dt;
     for (i = 0, ni = psb->m_nodes.size(); i < ni; ++i)
     {
         btSoftBody::Node& n = psb->m_nodes[i];
diff --git a/src/BulletSoftBody/btDeformableNeoHookeanForce.h b/src/BulletSoftBody/btDeformableNeoHookeanForce.h
index 797addf8b..816d214ef 100644
--- a/src/BulletSoftBody/btDeformableNeoHookeanForce.h
+++ b/src/BulletSoftBody/btDeformableNeoHookeanForce.h
@@ -73,7 +73,10 @@ public:
                 size_t id3 = node3->index;
                 btMatrix3x3 dF = DsFromVelocity(node0, node1, node2, node3) * tetra.m_Dm_inverse;
                 btMatrix3x3 dP;
-                firstPiolaDampingDifferential(psb->m_tetraScratchesTn[j], dF, dP);
+//                firstPiolaDampingDifferential(psb->m_tetraScratchesTn[j], dF, dP);
+                btMatrix3x3 I;
+                I.setIdentity();
+                dP = (dF + dF.transpose()) * m_mu_damp + I * (dF[0][0]+dF[1][1]+dF[2][2]) * m_lambda_damp;
                 btVector3 df_on_node0 = dP * (tetra.m_Dm_inverse.transpose()*grad_N_hat_1st_col);
                 btMatrix3x3 df_on_node123 = dP * tetra.m_Dm_inverse.transpose();
 
@@ -210,7 +213,10 @@ public:
                 size_t id3 = node3->index;
                 btMatrix3x3 dF = Ds(id0, id1, id2, id3, dv) * tetra.m_Dm_inverse;
                 btMatrix3x3 dP;
-                firstPiolaDampingDifferential(psb->m_tetraScratchesTn[j], dF, dP);
+//                firstPiolaDampingDifferential(psb->m_tetraScratchesTn[j], dF, dP);
+                btMatrix3x3 I;
+                I.setIdentity();
+                dP = (dF + dF.transpose()) * m_mu_damp + I * (dF[0][0]+dF[1][1]+dF[2][2]) * m_lambda_damp;
 //                btVector3 df_on_node0 = dP * (tetra.m_Dm_inverse.transpose()*grad_N_hat_1st_col);
                 btMatrix3x3 df_on_node123 = dP * tetra.m_Dm_inverse.transpose();
                 btVector3 df_on_node0 = df_on_node123 * grad_N_hat_1st_col;