Tendon#

class blueprints.Tendon[source]#

Bases: TendonType, NodeThing, ColoredThing, FocalThing

Attributes Summary

act_force_limited

Indicates whether the Actuator forces applied are limited.

actuatorfrclimited

Indicates whether the Actuator forces applied are limited.

actuatorfrcrange

The Actuator force range of the Tendon.

armature

Setting this attribute to a positive value \(m\) adds a kinetic energy term \(\frac{1}{2}mv^2\), where \(v\) is the tendon velocity.

damping

A positive value generates a damping force (linear in velocity) acting along the tendon.

frictionloss

Friction loss caused by dry friction.

limited

Indicates whether the Tendon length is limited by range.

max_act_force

Changing this value results in a change in the first component of actuatorfrcrange.

max_length

Changing this value results in a change in the first component of range.

min_act_force

Changing this value results in a change in the second component of actuatorfrcrange.

min_length

Changing this value results in a change in the second component of range.

range

The length range of the Tendon.

stiffness

A positive value generates a spring force (linear in position) acting along the Tendon.

width

This attribute is purely cosmetical.

Methods Summary

attach(*items[, copy])

Attachements are not allowed for Tendons.

Attributes Documentation

act_force_limited#

Indicates whether the Actuator forces applied are limited.

Returns:

In the attribute is None, the value is set to auto.

Return type:

bool | None

actuatorfrclimited#

Indicates whether the Actuator forces applied are limited.

Returns:

In the attribute is None, the value is set to auto.

Return type:

bool | None

actuatorfrcrange#

The Actuator force range of the Tendon.

Returns:

The two entries indicate minimum and maximum Actuator force applied to the Tendon.

Return type:

np.ndarray

armature#

Setting this attribute to a positive value \(m\) adds a kinetic energy term \(\frac{1}{2}mv^2\), where \(v\) is the tendon velocity.

Returns:

Inertia associated with changes in Tendon length

Return type:

float

damping#

A positive value generates a damping force (linear in velocity) acting along the tendon. If possible, Joint.damping should be used for stability.

Returns:

Tendon dampin.

Return type:

float

frictionloss#

Friction loss caused by dry friction.

Returns:

To enable friction loss, set this attribute to a positive value.

Return type:

float

limited#

Indicates whether the Tendon length is limited by range.

Returns:

In the attribute is None, the value is set to auto.

Return type:

bool | None

max_act_force#

Changing this value results in a change in the first component of actuatorfrcrange.

Returns:

Maximum force applicable by an Actuator

Return type:

float

max_length#

Changing this value results in a change in the first component of range.

The user should make sure, that the initial length of the tendon as computed by the distance between its bound Things does not exeed this attribute.

Returns:

Maximum length of the Tendon

Return type:

float

min_act_force#

Changing this value results in a change in the second component of actuatorfrcrange.

Returns:

Minimum force applicable by an Actuator

Return type:

float

min_length#

Changing this value results in a change in the second component of range.

Returns:

Minimum length of the Tendon

Return type:

float

range#

The length range of the Tendon.

Returns:

The two entries indicate minimum and maximum Tendon length.

Return type:

np.ndarray

stiffness#

A positive value generates a spring force (linear in position) acting along the Tendon.

Returns:

Stiffness of the Tendon

Return type:

float

width#

This attribute is purely cosmetical.

Returns:

Width of the Tendon.

Return type:

föoat

Methods Documentation

attach(*items, copy=False)[source]#

Attachements are not allowed for Tendons. Use Path.bind() instead.

Return type:

None

__init__(name=None, limited=None, act_force_limited=None, min_length=0.0, max_length=0.0, min_act_force=0.0, max_act_force=0.0, frictionloss=0.0, width=0.003, color=None, stiffness=0.0, damping=0.0, armature=0.0, **kwargs)[source]#

Some attribute descriptions are taken from Mujoco.

Parameters:

  • limited (bool | None) – Sets whether length limits constraints are imposed on the mujoco solver. Leaving this argument as None (recommended) enables autolimits derived from the other attributes.

  • act_force_limited (bool | None) – This argument is the equivalent to limited for actuator forces.

  • min_length (int | float) – Minimal length of Tendon

  • max_length (int | float) – Maximal length of Tendon

  • min_act_force (int | float) – Minimal force allowed to act on Tendon

  • max_act_force (int | float) – Maximal force allowed to act on Tendon

  • frictionloss (int | float) – Friction loss caused by dry friction. This value should be positive.

  • width (int | float) – Crosssection radius of the Tendon

  • stiffness (int | float) – If set to a positive value it acts as a Spring coefficient.

  • damping (int | float) – If set to a positive value it acts as a Damping coefficient.

  • armature (int | float) – Inertia associated with changes in tendon length

  • name (str | None)

  • color (object | None)

Return type:

None

classmethod __new__(*args, **kwargs)#