LIBRARY

RelativePosition

Measures the relative position vector between two frames.

This is a sensor: no forces or torques are exerted on either frame. The output is frame_b.r_0 - frame_a.r_0 resolved in the frame specified by resolve_in_frame.

Usage

MultibodyComponents.RelativePosition()

Parameters:

Name	Description	Units	Default value
resolve_in_frame		–	ResolveInFrame.FrameA()

Connectors

• frame_a - Frame3D is the fundamental 3D connector used for 6DOF motion. Most components have one or several Frame

connectors that can be connected together (Frame3D)

• frame_b - Frame3D is the fundamental 3D connector used for 6DOF motion. Most components have one or several Frame

connectors that can be connected together (Frame3D)

• r_rel_x - This connector represents a real signal as an output from a component (RealOutput)

• r_rel_y - This connector represents a real signal as an output from a component (RealOutput)

• r_rel_z - This connector represents a real signal as an output from a component (RealOutput)

Variables

Name	Description	Units
r_rel		m

Behavior

Dict{MIME{Symbol("text/plain")}, String} with 1 entry: MIME type text/plain => "Error displaying result"

Source

"""
Measures the relative position vector between two frames.

This is a sensor: no forces or torques are exerted on either frame.
The output is `frame_b.r_0 - frame_a.r_0` resolved in the
frame specified by `resolve_in_frame`.
"""
component RelativePosition
  frame_a = Frame3D() {
    "Dyad": {
      "placement": {
        "diagram": {"iconName": "default", "x1": -50, "y1": 450, "x2": 50, "y2": 550, "rot": 0}
      },
      "tags": []
    }
  }
  frame_b = Frame3D() {
    "Dyad": {
      "placement": {
        "diagram": {"iconName": "default", "x1": 950, "y1": 450, "x2": 1050, "y2": 550, "rot": 0}
      },
      "tags": []
    }
  }
  r_rel_x = RealOutput() {
    "Dyad": {
      "placement": {
        "diagram": {"iconName": "default", "x1": 130, "y1": 960, "x2": 230, "y2": 1060, "rot": 90}
      },
      "tags": []
    }
  }
  r_rel_y = RealOutput() {
    "Dyad": {
      "placement": {
        "diagram": {"iconName": "default", "x1": 450, "y1": 960, "x2": 550, "y2": 1060, "rot": 90}
      },
      "tags": []
    }
  }
  r_rel_z = RealOutput() {
    "Dyad": {
      "placement": {
        "diagram": {"iconName": "default", "x1": 770, "y1": 960, "x2": 870, "y2": 1060, "rot": 90}
      },
      "tags": []
    }
  }
  structural parameter resolve_in_frame::ResolveInFrame = ResolveInFrame.FrameA()
  variable r_rel::Dyad.Position[3]
relations
  # Sensor exerts no forces or torques
  frame_a.f = [0, 0, 0]
  frame_a.tau = [0, 0, 0]
  frame_b.f = [0, 0, 0]
  frame_b.tau = [0, 0, 0]
  switch resolve_in_frame
    case FrameA
      r_rel = resolve2(frame_a.R, frame_b.r_0 - frame_a.r_0)
    case FrameB
      r_rel = resolve2(frame_b.R, frame_b.r_0 - frame_a.r_0)
    case World
      r_rel = frame_b.r_0 - frame_a.r_0
  end
  [r_rel_x, r_rel_y, r_rel_z] = r_rel
metadata {
  "Dyad": {
    "icons": {"default": "dyad://MultibodyComponents/TwoFrameSensor.svg"},
    "labels": [
      {
        "label": "$(instance)",
        "x": 500,
        "y": 150,
        "rot": 0,
        "attrs": {"font-size": "140"}
      },
      {"label": "rel pos", "x": 500, "y": 680, "rot": 0}
    ]
  }
}
end

Flattened Source

"""
Measures the relative position vector between two frames.

This is a sensor: no forces or torques are exerted on either frame.
The output is `frame_b.r_0 - frame_a.r_0` resolved in the
frame specified by `resolve_in_frame`.
"""
component RelativePosition
  frame_a = Frame3D() {
    "Dyad": {
      "placement": {
        "diagram": {"iconName": "default", "x1": -50, "y1": 450, "x2": 50, "y2": 550, "rot": 0}
      },
      "tags": []
    }
  }
  frame_b = Frame3D() {
    "Dyad": {
      "placement": {
        "diagram": {"iconName": "default", "x1": 950, "y1": 450, "x2": 1050, "y2": 550, "rot": 0}
      },
      "tags": []
    }
  }
  r_rel_x = RealOutput() {
    "Dyad": {
      "placement": {
        "diagram": {"iconName": "default", "x1": 130, "y1": 960, "x2": 230, "y2": 1060, "rot": 90}
      },
      "tags": []
    }
  }
  r_rel_y = RealOutput() {
    "Dyad": {
      "placement": {
        "diagram": {"iconName": "default", "x1": 450, "y1": 960, "x2": 550, "y2": 1060, "rot": 90}
      },
      "tags": []
    }
  }
  r_rel_z = RealOutput() {
    "Dyad": {
      "placement": {
        "diagram": {"iconName": "default", "x1": 770, "y1": 960, "x2": 870, "y2": 1060, "rot": 90}
      },
      "tags": []
    }
  }
  structural parameter resolve_in_frame::ResolveInFrame = ResolveInFrame.FrameA()
  variable r_rel::Dyad.Position[3]
relations
  # Sensor exerts no forces or torques
  frame_a.f = [0, 0, 0]
  frame_a.tau = [0, 0, 0]
  frame_b.f = [0, 0, 0]
  frame_b.tau = [0, 0, 0]
  switch resolve_in_frame
    case FrameA
      r_rel = resolve2(frame_a.R, frame_b.r_0 - frame_a.r_0)
    case FrameB
      r_rel = resolve2(frame_b.R, frame_b.r_0 - frame_a.r_0)
    case World
      r_rel = frame_b.r_0 - frame_a.r_0
  end
  [r_rel_x, r_rel_y, r_rel_z] = r_rel
metadata {
  "Dyad": {
    "icons": {"default": "dyad://MultibodyComponents/TwoFrameSensor.svg"},
    "labels": [
      {
        "label": "$(instance)",
        "x": 500,
        "y": 150,
        "rot": 0,
        "attrs": {"font-size": "140"}
      },
      {"label": "rel pos", "x": 500, "y": 680, "rot": 0}
    ]
  }
}
end

Test Cases

No test cases defined.

Related

• Examples

• Experiments

• Analyses

• Tests

  • SensorsTest