I found the issue here. Setting the "sampling rate" in the trc/mot file to 100 Hz made the system stable!
Makes sense to me. So then I tried to increase the complexity of the model towards my goal system.
- Adding the other upper arm: works fine.
- putting this on top of a "boat-box" that is connect with another slider (called bJoint_3) to be able to move the boat: works fine.
This last slider is explicitly NOT being made a task in bb_CMC_Tasks.xml, the whole idea is to determine the value of it!
- Adding an upper leg and the upper half of a lower leg to the hip, and the lower half of the lower leg to a pinjoint on the boat: works fine.
- Adding a weldconstraint to connect the 2 lower leg parts: this crashes trying to compute the first time step!
The CMC_simple directory on github, see above, is updated to contain this last (selfcontained) example.
- The model that crashes
- cmc_simple_2.png (98.71 KiB) Viewed 488 times
Below the std-output of OpenSim.
Code: Select all
new OPENSIM_HOME =/home/sietse/Software/OpenSim/opensim-OK
Web Root URI: %s%nfile:/home/sietse/Software/OpenSim/opensim-OK/
Loading plugins from directory /home/sietse/.opensim/plugins
[info] Loaded model BootBaan from file /home/sietse/Roeien/Modelling/Rowing/BootBaan/CMC_simple/BootBaan.osim
Connected... adding peer
[info] Running tool 'CMC_row_subject'.
[info] No external loads will be applied (external loads file not specified).
[info] TaskSet size = 11.
[warning] A desired points file was not specified.
[info] Loading desired kinematics from file '/home/sietse/Roeien/Modelling/Rowing/BootBaan/CMC_simple/trajectory.mot'...
[info] Storage: read data file = /home/sietse/Roeien/Modelling/Rowing/BootBaan/CMC_simple/trajectory.mot (nr=593 nc=13)
[info] Not filtering the desired kinematics.
MODEL: BootBaan
numStates = 26
numCoordinates = 12
numSpeeds = 12
numActuators = 12
numBodies = 14
numConstraints = 1
numProbes = 0
ANALYSES (total: 3)
analysis[0] = MetabolicsReporter
analysis[1] = Un-named analysis.
analysis[2] = Un-named analysis.
BODIES (total: 14)
body[0] = Rowing_course. mass: 1
moments of inertia: ~[1,1,1]
products of inertia: ~[0,0,0]
body[1] = TheBoat. mass: 10
moments of inertia: ~[7.50833,7.50833,45]
products of inertia: ~[0,0,0]
body[2] = Stretcher. mass: 1
moments of inertia: ~[0.0108333,0.0108333,0.045]
products of inertia: ~[0,0,0]
body[3] = Seat. mass: 1
moments of inertia: ~[1,1,1]
products of inertia: ~[0,0,0]
body[4] = Bow. mass: 0.1
moments of inertia: ~[1,1,1]
products of inertia: ~[0,0,0]
body[5] = Lower_leg_lower. mass: 4
moments of inertia: ~[1,1,1]
products of inertia: ~[0,0,0]
body[6] = Lower_leg_upper. mass: 4
moments of inertia: ~[1,1,1]
products of inertia: ~[0,0,0]
body[7] = Upper_leg. mass: 8
moments of inertia: ~[1,1,1]
products of inertia: ~[0,0,0]
body[8] = Lower_back. mass: 16
moments of inertia: ~[1,1,1]
products of inertia: ~[0,0,0]
body[9] = Upper_back. mass: 16
moments of inertia: ~[1,1,1]
products of inertia: ~[0,0,0]
body[10] = Shoulder. mass: 8
moments of inertia: ~[1,1,1]
products of inertia: ~[0,0,0]
body[11] = Head. mass: 8
moments of inertia: ~[1,1,1]
products of inertia: ~[0,0,0]
body[12] = Upper_Arm_Left. mass: 4
moments of inertia: ~[1,1,1]
products of inertia: ~[0,0,0]
body[13] = Upper_Arm_Right. mass: 4
moments of inertia: ~[1,1,1]
products of inertia: ~[0,0,0]
JOINTS (total: 14)
joint[0] = courseJoint. parent: ground_offset, child: Rowing_course_offset
joint[1] = boatJoint. parent: ground_offset, child: TheBoat_offset
joint[2] = stretcherJoint. parent: TheBoat_offset, child: Stretcher_offset
joint[3] = seatJoint. parent: TheBoat_offset, child: Seat_offset
joint[4] = bowJoint. parent: TheBoat_offset, child: Bow_offset
joint[5] = hipJoint. parent: Seat_offset, child: Upper_leg_offset
joint[6] = knee_Joint. parent: Upper_leg_offset, child: Lower_leg_upper_offset
joint[7] = foot_Joint. parent: Stretcher_offset, child: Lower_leg_lower_offset
joint[8] = lbackJoint. parent: Seat_offset, child: Lower_back_offset
joint[9] = ubackJoint. parent: Lower_back_offset, child: Upper_back_offset
joint[10] = shoulderJoint. parent: Upper_back_offset, child: Shoulder_offset
joint[11] = headJoint. parent: Shoulder_offset, child: Head_offset
joint[12] = upper_arm_left_Joint. parent: Shoulder_offset, child: Upper_Arm_Left_offset
joint[13] = upper_arm_right_Joint. parent: Shoulder_offset, child: Upper_Arm_Right_offset
ACTUATORS (total: 12)
actuator[0] = bJ_act_3
actuator[1] = seatact
actuator[2] = hipact
actuator[3] = kneeact
actuator[4] = footact
actuator[5] = lbackact
actuator[6] = ualo_act
actuator[7] = ualt_act
actuator[8] = ualu_act
actuator[9] = uaro_act
actuator[10] = uart_act
actuator[11] = uaru_act
STATES (total: 24)
y[0] = /jointset/boatJoint/bJoint_3/value
y[1] = /jointset/boatJoint/bJoint_3/speed
y[2] = /jointset/seatJoint/seatpos/value
y[3] = /jointset/seatJoint/seatpos/speed
y[4] = /jointset/hipJoint/hipangle/value
y[5] = /jointset/hipJoint/hipangle/speed
y[6] = /jointset/knee_Joint/kneeangle/value
y[7] = /jointset/knee_Joint/kneeangle/speed
y[8] = /jointset/foot_Joint/footangle/value
y[9] = /jointset/foot_Joint/footangle/speed
y[10] = /jointset/lbackJoint/lbackangle/value
y[11] = /jointset/lbackJoint/lbackangle/speed
y[12] = /jointset/upper_arm_left_Joint/uarmleft_out/value
y[13] = /jointset/upper_arm_left_Joint/uarmleft_out/speed
y[14] = /jointset/upper_arm_left_Joint/uarmleft_trn/value
y[15] = /jointset/upper_arm_left_Joint/uarmleft_trn/speed
y[16] = /jointset/upper_arm_left_Joint/uarmleft_up/value
y[17] = /jointset/upper_arm_left_Joint/uarmleft_up/speed
y[18] = /jointset/upper_arm_right_Joint/uarmright_out/value
y[19] = /jointset/upper_arm_right_Joint/uarmright_out/speed
y[20] = /jointset/upper_arm_right_Joint/uarmright_trn/value
y[21] = /jointset/upper_arm_right_Joint/uarmright_trn/speed
y[22] = /jointset/upper_arm_right_Joint/uarmright_up/value
y[23] = /jointset/upper_arm_right_Joint/uarmright_up/speed
[info] AssemblySolver::track() attempt Failed: SimTK Exception thrown at Assembler.cpp:971:
Method Assembler::track() failed because:
Unable to achieve required assembly error tolerance.
Assembly error tolerance achieved: 1.5682095300458139e-08 required: 1e-10.
[error] Model unable to assemble: AssemblySolver::assemble() Failed: SimTK Exception thrown at Assembler.cpp:895:
Method Assembler::assemble() failed because:
Unable to achieve required assembly error tolerance.
Assembly error tolerance achieved: 1.5682080701025365e-08 required: 1e-10..Model relaxing constraints and trying again.
[info] Constructing function set for tracking desired kinematics...
[info] No Actuation analysis found in analysis set -- adding one...
[info] No Kinematics analysis found in analysis set -- adding one...
[info] Using the generalized coordinates specified in /home/sietse/Roeien/Modelling/Rowing/BootBaan/CMC_simple/trajectory.mot to set the initial configuration.
[info] Using IPOPT optimizer algorithm.
[info] Setting optimizer print level to 3.
[info] Setting optimizer convergence tolerance to 1.0e-05.
[info] Setting optimizer maximum iterations to 1000.
[info] Setting cmc controller to use verbose printing.
[info] CMC::computeControls, t = 0.0
[info] -- step size = 1.0e-08, target time = 1.0e-08
[info] ------------------------------
[info] CMC::computeControls, summary:
[info] ------------------------------
[info] -- Q = ~[5.73972e-42 -0.656532 0.41083 1.37093 0.199706 2.5309 0.663378 -0.504364 -0.0993496 4.23457e-32 0.656969 -0.460442 -0.0353807 1.28321e-33]
[info] -- U = ~[-6.71959e-24 0.706071 0.542015 -0.994904 0.00301259 -1.53692 0.760848 1.53081 -6.32736 0.916102 1.21376 -6.46196]
[info] -- Z = ~[]
[info] -- Qdesired = 5.73972e-42 -0.656533 0.410829 2.5309 1.37093 0.199706 0.663378 -0.504364 -0.0993496 0.65697 -0.460442 -0.0353806
[info] -- Udesired = -6.71961e-24 0.704209 0.551872 -1.54136 -0.989947 0.0030162 0.760862 1.53074 -6.32765 0.91614 1.21368 -6.46225
[info] -- Qcorrection = 2.17634e-49 5.35037e-07 7.46902e-07 -4.61961e-07 -6.35618e-09 -3.80285e-09 -6.06432e-08 6.61633e-08 -1.50523e-08 -6.16565e-08 6.51038e-08 -1.50301e-08
[info] -- Ucorrection = 2.28052e-29 0.00186202 -0.00985754 0.00444144 -0.0049571 -3.61482e-06 -1.34788e-05 7.21129e-05 0.000289815 -3.7365e-05 7.17767e-05 0.000281073
[info] ------------------------------
[info]
[info] Errors at time 0.0:
[warning] Task 'seatpos': pErr = -5.35037e-07, vErr = 0.0.
[info]
[warning] Task 'hipangle': pErr = -7.46902e-07, vErr = 0.0.
[info]
[warning] Task 'kneeangle': pErr = 4.61961e-07, vErr = 0.0.
[info]
[warning] Task 'footangle': pErr = 6.35618e-09, vErr = 0.0.
[info]
[warning] Task 'lbackangle': pErr = 3.80285e-09, vErr = 0.0.
[info]
[warning] Task 'uarmleft_out': pErr = 6.06432e-08, vErr = 0.0.
[info]
[warning] Task 'uarmleft_trn': pErr = -6.61633e-08, vErr = 0.0.
[info]
[warning] Task 'uarmleft_up': pErr = 1.50523e-08, vErr = 0.0.
[info]
[warning] Task 'uarmright_out': pErr = 6.16565e-08, vErr = 0.0.
[info]
[warning] Task 'uarmright_trn': pErr = -6.51038e-08, vErr = 0.0.
[info]
[warning] Task 'uarmright_up': pErr = 1.50301e-08, vErr = 0.0.
[info]
[info] xmin: -10000 -10000 -10000 -10000 -10000 -10000 -10000 -10000 -10000 -10000 -10000 -10000
[info] xmax: 10000 10000 10000 10000 10000 10000 10000 10000 10000 10000 10000 10000
[info]
[info] tiReal = 0.0, tfReal = 1.0e-08
[info] Min forces: -10000 -10000 -10000 -10000 -10000 -10000 -10000 -10000 -10000 -10000 -10000 -10000
[info] Max forces: 10000 10000 10000 10000 10000 10000 10000 10000 10000 10000 10000 10000
[info]
Total number of variables............................: 12
variables with only lower bounds: 0
variables with lower and upper bounds: 12
variables with only upper bounds: 0
Total number of equality constraints.................: 11
Total number of inequality constraints...............: 0
inequality constraints with only lower bounds: 0
inequality constraints with lower and upper bounds: 0
inequality constraints with only upper bounds: 0
Number of Iterations....: 224
(scaled) (unscaled)
Objective...............: 1.3206253192025302e+04 1.3206253192025302e+04
Dual infeasibility......: 2.2112779757943107e+02 2.2112779757943107e+02
Constraint violation....: 9.9613298614424525e+02 2.7842054820207704e+03
Complementarity.........: 9.0909092501173333e-07 9.0909092501173333e-07
Overall NLP error.......: 9.9613298614424525e+02 2.7842054820207704e+03
Number of objective function evaluations = 1489
Number of objective gradient evaluations = 220
Number of equality constraint evaluations = 1489
Number of inequality constraint evaluations = 0
Number of equality constraint Jacobian evaluations = 271
Number of inequality constraint Jacobian evaluations = 0
Number of Lagrangian Hessian evaluations = 0
Total CPU secs in IPOPT (w/o function evaluations) = 0.619
Total CPU secs in NLP function evaluations = 0.016
EXIT: Converged to a point of local infeasibility. Problem may be infeasible.
[error] SimTK Exception thrown at InteriorPointOptimizer.cpp:264:
Optimizer failed: Ipopt: Infeasible problem detected (status 2)
[error] OPTIMIZATION FAILED...
[error] CMC::computeControls: Optimizer could not find a solution.
Unable to find a feasible solution at time = 0.
Model cannot generate the forces necessary to achieve the target acceleration.
Possible issues: 1. not all model degrees-of-freedom are actuated,
2. there are tracking tasks for locked coordinates, and/or
3. there are unnecessary control constraints on reserve/residual actuators.
I see
Code: Select all
Unable to achieve required assembly error tolerance.
Assembly error tolerance achieved: 1.5682080701025365e-08 required: 1e-10..Model relaxing constraints and trying again.
[info] Constructing function set for tracking desired kinematics...
This occurs often and doesn't seem to be a problem, correct?
Then:
Code: Select all
EXIT: Converged to a point of local infeasibility. Problem may be infeasible.
[error] SimTK Exception thrown at InteriorPointOptimizer.cpp:264:
Optimizer failed: Ipopt: Infeasible problem detected (status 2)
[error] OPTIMIZATION FAILED...
[error] CMC::computeControls: Optimizer could not find a solution.
Unable to find a feasible solution at time = 0.
I now am stuck again
Adding the weldconstraint makes CMC crash. This should cause the boat to move a bit and it would be more difficult to get a larger acceleration, I see that. Note that I also tried an extremely slow trajectory but that crashes just the same.
I don't use RRA, and actually don't know how to use it. There are no muscles in the model, only coordinate actuators.
They have no a limit on the force like muscles, so no need for reserve actuators. Am I making sense here?
In "Getting Started with CMC" it is stated: The fast target requires the joint accelerations at each time step to be matched to the RRA results...
This suggests that RRA is to be done?
In the generated files
desiredKinematics_splinefit_accelerations.sto and
desiredKinematics_padded.sto I see that calculation from 0.6 seconds is done
before the start of the session.
There are wildely varying values for values and speeds. CMC is trying to determine a proper initial setting?
In "How CMC Works" there is talk about initial values for generalized coordinates and speeds.
Is there a way to set these speed? How? Would this help? My first guess would be to zet speeds to zero.
What can I do now? Thanks in advance.
Sietse