The SLQ in OCS2 12.0 seems to have numerical stability issue when the mode schedule is not empty, for example the mode schedule shown below (ds means double support mode):
ds ds ds ds ds ds ds ds ds ds ds ds ds ds ds
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5
and a constant state feedback (always x0), will quickly cause the SLQ riccati equation to diverge with warm start after a few iteration:
If warm start is not used, it seems like the divergence will not happen.
The divergence gets faster as the interval between modes decreases.
The thread is set 1.
The SLQ in OCS2 12.0 seems to have numerical stability issue when the mode schedule is not empty, for example the mode schedule shown below (
dsmeans double support mode): ds ds ds ds ds ds ds ds ds ds ds ds ds ds ds 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5 and a constant state feedback (always x0), will quickly cause the SLQ riccati equation to diverge with warm start after a few iteration:Integration terminated since the maximum number of function calls is reached. State at termination time -0.891556: [ -3.68056e+94 3.26466e+99 -2.89575e+104 -4.7569e+90 4.21937e+95 -6.14801e+86 -6.40359e+100 5.67998e+105 -8.27625e+96 -1.11412e+107 6.48803e+96 -5.75488e+101 8.38538e+92 1.12881e+103 -1.1437e+99 -2.31334e+100 2.05193e+105 -2.98985e+96 -4.02484e+106 4.07791e+102 -1.454e+106 -2.60803e+93 2.31332e+98 -3.37072e+89 -4.53755e+99 4.59739e+95 -1.63922e+99 -1.84804e+92 5.71019e+98 -5.06494e+103 7.38008e+94 9.93482e+104 -1.00658e+101 3.58902e+104 4.04622e+97 -8.85905e+102 -1.76817e+89 1.56836e+94 -2.28525e+85 -3.07633e+95 3.11689e+91 -1.11134e+95 -1.25292e+88 2.74322e+93 -8.49439e+83 -5.96575e+98 5.29162e+103 -7.71037e+94 -1.03794e+105 1.05163e+101 -3.74964e+104 -4.2273e+97 9.25553e+102 -2.86599e+93 -9.66976e+102 2.29358e+95 -2.03441e+100 2.96431e+91 3.99046e+101 -4.04308e+97 1.44158e+101 1.62522e+94 -3.55837e+99 1.10185e+90 3.71762e+99 -1.42927e+96 -3.18932e+99 2.82893e+104 -4.12201e+95 -5.54891e+105 5.62208e+101 -2.00458e+105 -2.25994e+98 4.94806e+103 -1.53217e+94 -5.16951e+103 1.98746e+100 -2.76365e+104 1.23296e+94 -1.09363e+99 1.59352e+90 2.14514e+100 -2.17343e+96 7.74948e+99 8.73667e+92 -1.91286e+98 5.9232e+88 1.99847e+98 -7.68329e+94 1.06839e+99 -4.13029e+93 -1.48445e+99 1.31671e+104 -1.91856e+95 -2.5827e+105 2.61676e+101 -9.33019e+104 -1.05187e+98 2.30304e+103 -7.13139e+93 -2.40611e+103 9.2505e+99 -1.28632e+104 4.97277e+98 -5.9871e+103 -2.01347e+90 1.78595e+95 -2.60229e+86 -3.50311e+96 3.54931e+92 -1.26552e+96 -1.42674e+89 3.12379e+94 -9.67284e+84 -3.26359e+94 1.25471e+91 -1.74473e+95 6.74494e+89 -8.12075e+94 -1.10148e+86 1.23296e+94 -1.09363e+99 1.59352e+90 2.14514e+100 -2.17343e+96 7.74948e+99 8.73667e+92 -1.91286e+98 5.9232e+88 1.99847e+98 -7.68329e+94 1.06839e+99 -4.13029e+93 4.97277e+98 6.74494e+89 -4.13029e+93 -1.48445e+99 1.31671e+104 -1.91856e+95 -2.5827e+105 2.61676e+101 -9.33019e+104 -1.05187e+98 2.30304e+103 -7.13139e+93 -2.40611e+103 9.2505e+99 -1.28632e+104 4.97277e+98 -5.9871e+103 -8.12075e+94 4.97277e+98 -5.9871e+103 2.01426e+90 -1.78665e+95 2.60331e+86 3.50449e+96 -3.5507e+92 1.26602e+96 1.42729e+89 -3.12501e+94 9.67663e+84 3.26487e+94 -1.25521e+91 1.74542e+95 -6.74758e+89 8.12393e+94 1.10191e+86 -6.74758e+89 8.12393e+94 -1.10234e+86 -6.75657e+93 5.99308e+98 -8.73246e+89 -1.17553e+100 1.19104e+96 -4.2467e+99 -4.78767e+92 1.04824e+98 -3.2459e+88 -1.09516e+98 4.21042e+94 -5.85478e+98 2.26339e+93 -2.72507e+98 -3.69621e+89 2.26339e+93 -2.72507e+98 3.69766e+89 -6.20166e+92]
If warm start is not used, it seems like the divergence will not happen. The divergence gets faster as the interval between modes decreases. The thread is set 1.