Fix ABA for models without joints

ami-iit · Jun 30, 2023 · 30f057e · 30f057e
1 parent b399c6a
commit 30f057e
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/src/jaxsim/physics/algos/aba.py b/src/jaxsim/physics/algos/aba.py
@@ -95,7 +95,7 @@ def loop_body_pass1(carry: Pass1Carry, i: jtp.Int) -> Tuple[Pass1Carry, None]:
         i_X_λi = i_X_λi.at[i].set(i_X_λi_i)
 
         # Propagate link velocity
-        vJ = S[i] * qd[ii]
+        vJ = S[i] * qd[ii] if qd.size != 0 else S[i] * 0
 
         v_i = i_X_λi[i] @ v[λ[i]] + vJ
         v = v.at[i].set(v_i)