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Any number of available analyses can be added to a CMC run. To get a listing of available analyses, open the CMC tool in the GUI and go the the Analyses pane and click on Add or see the __40__Analyses chapter.

There are several properties associated with the analyses results. <results_directory> specifies the directory where results should be written. <output_precision> specifies how many decimal places should be used when writing results. A value of 20 is sufficient to avoid round-off error when reading results back in during other steps in the workflow. <step_interval> specifies how often to record results during numerical integration. A value of 10 means record results every 10 integration steps.

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There can be multiple sets of ground reaction forces for different locations on the body. These are specified in the file identified by the <external_loads_file> tags. The external loads .xml file specifies the source file for input forces and to which location and body the forces are to be applied. See __40__ Inverse Dynamics for additional details for applying any number of external loads as point forces and/or body torques. 

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A number of properties are available for controlling the optimizer. <use_fast_ optimization_target> specifies whether the fast or slow optimization target should be used (__40__How RRA Works). <optimizer_derivative_dx> specifies the perturbation size in the controls for computing numerical derivatives. <optimizer_convergence_criterion> specifies a convergence criterion; the smaller this value, the deeper the convergence. <optimizer_max_iterations> specifies an iteration limit for each time step. <optimizer_print_level> allows diagnostic information to be printed. The larger the number (up to a maximum of 3), the more information that is printed.

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A number of properties are available for controlling the CMC algorithm proper. <cmc_time_window> specifies the time allowed for time-dependent actuators like muscles to change force. If the window is too small, actuator forces will not have enough freedom to generate the desired accelerations. If the window is too large, the control will be too coarse to allow for good tracking (__40__How RRA Works). <use_curvature_filter> specifies whether or not to apply a curvature filter to computed excitations. If control values are oscillating, the curvature filter can used to attenuate these oscillations. To apply the curvature filter, set <use_curvature_filter> to true. <adjust_com_to_reduce_residuals> is a property used for residual reduction (Chapter 3). During CMC, this property should be set to false.

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The property <on> is used to turn a task on or off. The <active> property specifies which component of task is active. While other task types might have three components, joint tasks only have one, so the typical setting is true false false. Properties <kp> and <kv> specify the position and velocity error gains, respectively. See __40__ How RRA Works for an explanation of error gains. The <coordinate> property specifies to which model coordinate a task applies. The value of the property must agree with the name of the model coordinate exactly. Joints can be translational (e.g., pelvis_tz) or rotational (e.g., hip_flexion_r).

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Residual actuators are actuators that act directly between the model and the ground. These are used to control the global position and orientation of a model. If the residuals for a simulation have been reduced (see __40__ Residual Reduction Algorithm), the loads applied by these actuators should be relatively small. However, unlike muscles, the residual actuators can apply negative as well as positive forces. The minimum and maximum control values here, therefore, differ from the default values set at the top of the example file (0.02 and 1.0) and must be specified explicitly (-1.0 and 1.0).

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