04 - Control System; Functional Description; Functional Block Diagram - Nilfisk-Advance Advance Liberty SC50 Series Service Manual

Service Manual – Liberty SC50

04 - Control System

Functional Description

The easiest way to understand the Liberty system is to divide it into its various controllers or modules.
Each subsystem performs specific tasks, but also communicate with one another to create a unified control
system. However, the Autonomous (self-driving) system is relatively isolated from the other systems, and is
discussed in its own chapter.
The division of the Liberty System by logic function starts with the Main Machine Controller (MMC). As the
name implies, this acts as the central controller that ties all of the other modules together. These functions
are summarized below, and explained in greater detail in subsequent sections.
Module Bus
Main CANBus-0
Machine CANBus-1
Controller
Onboard CANBus-0
Charger Interlock
Li-Ion CANBus-0
Batteries
Power CANBus-1
Module
Drive CANBus-1
Module Auto-OK
Steering
OK
Steering CANBus-1
Module Steering
OK
Autonomy CANBus-0
Module
Telematics CANBus-0
(Optional)

Functional Block Diagram

The Functional Block Diagram on the following page represents a high-level overview of the system
interactions and communications. It is not intended to show every component or connection. For a more
detailed examination of system interconnections, refer to the
Electrical System Chapter.
Function
• Commands the Power Module when and how to operate the brush motor, vacuum
motor, and deck lift actuator.
• Receives and interprets commands (CANBus-0) from the Autonomous system
and conveys this to other systems (CANBus-1):
− Commands the Wheel Drive Module when in Autonomous mode.
− Commands the Steering Module when in Autonomous mode.
• Communicates with the onboard battery charger (CANBus-0)
• Monitors and charges the batteries when connected to facility power (AC Mains
Power)
• Communicates with the Main Machine Controller regarding battery status and
charging parameters.
• Communicates with the on-board charger for charge profile and status.
• Communicates with the MMC for battery status.
• Receives commands from the MMC regarding motor operation.
• Provides status to the Main Machine Controller regarding motor operation.
• Controls and monitors the wheel motor.
• In manual mode, receives go and speed information directly from the operator
controls. Receives direction control from Main Machine Controller.
• In autonomous mode, receives all commands from the Main Machine Controller
(CANBus-1)
• In either mode, receives enable/disable commands from both the autonomous
system and steering system.
• In manual mode, receives steering command from the steering sensor.
• In autonomous mode, receives steering commands from Main Machine Controller.
• Enables the Wheel Controller when steering is ready.
• Receives information about the surrounding environment from sensors.
• Receives scrubbing machine information from the MMC.
• Sends autonomous driving and scrubbing commands to the MMC.
• Uses the cellular network to communicate with remote data logging system.
• Uses the GPS system for positional data logging.
• Receives status and data from the Main Machine Controller for data logging.
"Wiring Diagrams" on page 268 of the
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