67 lines
2.5 KiB
ReStructuredText
67 lines
2.5 KiB
ReStructuredText
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Hardware Setup
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BAM's identification pipeline requires a pendulum test bench with variable
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loads and lengths to increase the variety of the collected logs. The pendulum
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is attached directly to the actuator's output shaft, optionally using a
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counter-shaft when the actuator supports it.
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To present the identification process, the Dynamixel XL-330 motor is used as
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a case study. The instructions are similar for other actuators, adjusting only
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for the mass and length parameters.
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Requirements
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------------
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The hardware required for the identification process is as follows:
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- **A set of rigid arms of varying lengths**.
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The mass of the arms should be negligible compared to the attached loads.
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Therefore, it is recommended to use 3D-printed or laser-cut wooden arms for
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smaller motors handling light loads, and to reserve metal arms for more
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powerful motors.
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- **A set of weights compatible with the arms**.
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The masses must be heavy enough to generate a wide range of load torques.
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- **A mounting bracket for the actuator**.
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The setup must ensure that the actuator remains firmly secured during data
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logging, despite the fast movements of the weights at the end of the arm. The
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arm-weight assemblies must have sufficient clearance to oscillate between
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+/- 90° relative to the vertical position.
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- **A communication interface for the actuator**.
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Once the hardware is gathered, you must record the mass of the weights as well
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as the length and mass of the arms. These parameters are mandatory for the identification process.
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Example: Dynamixel XL-330
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-------------------------
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Here is an example of a test bench for the Dynamixel XL-330 actuator.
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The pendulum arms are 3D printed; you can refer to the 3D model for inspiration
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`here <https://cad.onshape.com/documents/c132b33797dc72aa58be8a7c/v/d9921c19039fee61b5e51bba/e/8e6b266057c61625732fd9b0?renderMode=0&uiState=6a447ab873e2fce629279db5>`_.
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.. image:: /_static/hardware_1.png
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:width: 80%
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:align: center
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:alt: 3D-printed pendulum test bench for the Dynamixel XL-330
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The interface with the actuator is established using a U2D2 kit.
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.. image:: /_static/hardware_2.png
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:width: 80%
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:align: center
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:alt: U2D2 communication interface
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The complete setup is shown below. The pendulum is attached to the
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actuator's output shaft, and the masses are fixed to the end of the
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pendulum arm.
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.. image:: /_static/hardware_3.png
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:width: 80%
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:align: center
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:alt: Complete Dynamixel XL-330 test bench setup
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