Brake Configuration

In some cases, the motor is equipped with a mechanical brake which can be released by applying electrical voltage to the brake’s terminals. The brake can be used to fix the motor shaft in a given position, for example for holding up a robot’s arm.

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A configurable voltage is applied to the positive terminal of motor brake (It is assumed that the negative terminal of the brake is connected to Ground).

When the motion service allows motion, the specified “Pull voltage” will be generated for a configurable amount of time designated as “Pull time”. After this time period, the second voltage level (Hold voltage) will be applied to the brake terminals permanently. The brake hold voltage can be set to a lower value to save energy.

Note

Don’t set the hold voltage too low or you risk entering a marginally stable situation where any jerk can engage the brake.

Once the motion system leaves the state “operation enabled” the generated voltage is automatically dropped to Ground after the designated time “Brake engage delay” and the brake is mechanically activated.

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The brake controller raises the torque progressively until it reaches the max. displacement threshold. If it reaches the maximum torque threshold first, it rises the torque again in the opposite direction. When the torque is high enough to compensate gravity, the load is lifted until the position reaches the threshold value, the torque stays to a holding torque value and the brake will be disengaged. After the release delay, the brake voltage is driven to Hold voltage and Op Mode display is set to Op Mode. The controller is then enabled.

Note

The brake release is an open loop system. After the brake pull time it is assumed that releasing was successful and the hold voltage is applied.

Brake Parameter Object

Description of all parameters used for brake release.