Pump and controls for electric motor gearbox with integrated brake

A driveline for a tracked vehicle, the driveline comprising:

• an electric motor;
• a track;
• a gearbox configured to be driven by the electric motor and drive the track, the gearbox comprising a first planetary gear set, a second planetary gear set, a first brake, and a second brake;
• a hydraulic system;
• and
• a control system comprising processing circuitry configured to:
• obtain one or more control inputs comprising at least one of a brake request or a mode selection;
• operate the hydraulic system of the tracked vehicle to transition the gearbox between a park mode, a neutral mode, a first driving mode, and a second driving mode according to the mode selection;
• and
• operate the hydraulic system of the tracked vehicle to provide variable pressurization to a chamber corresponding to one of the first brake or the second brake in order to perform the brake request while operating according to the first driving mode or the second driving mode.

A method of controlling a driveline of a tracked vehicle, the method comprising:

• providing a gearbox including a first planetary gear set, a second planetary gear set, a first brake, and a second brake, wherein a sun gear of the first planetary gear set and a sun gear of the second planetary gear set are fixedly coupled with an output shaft of an electric motor and the first brake and the second brake are configured to transition into engaged states to limit rotation of a sun gear of the first planetary gear set or the second planetary gear set;
• transitioning, responsive to a user input, the gearbox between a park mode by operating a hydraulic system to transition both the first brake and the second brake into engaged states, a neutral mode by operating the hydraulic system to transition both the first brake and the second brake into disengaged states, a first driving mode by operating the hydraulic system to transition the first brake into the engaged state and the second brake into the disengaged state, or a second driving mode by operating the hydraulic system to transition the second brake into the engaged state and the first brake into the disengaged state;
• responsive to both (i) the gearbox being in either the first driving mode or the second driving mode, and (ii) receiving an input to perform braking, operating the hydraulic system to provide variable pressurization to a disengaged one of the first brake or the second brake to provide braking.