Telemetry Board

Overview

• Board used: STM32f767zi
• Function: The communication between the pod and the base station, the state machine, etc.

Communication within this board

Within this board, the communication within tasks is done by channels (e.g.: PubSubChannel's in embassy-sync) There are:

• CAN_SEND and CAN_RECEIVE: When a CAN message is received, it will be put in CAN_RECEIVE, and when a CAN message needs to be sent, it will be put in CAN_SEND.
• EVENT_BUS: The state machine task will publish updates on this bus

Communication with other boards

CanMessage is used for all possible messages

#[derive(PartialEq, Debug, Clone, defmt::Format)]
pub enum CanMessage {
    MeasurementReading(MeasurementReading),
    Heartbeat(Heartbeat),
    Emergency(Board, Reason),

    // Electronics
    StartPrechargeCommand,
    StartDischargeCommand,
    PrechargeStarted,
    DischargeStarted,
    PrechargeComplete,
    DischargeComplete,
    VoltageStatus {
        voltage: Voltage,
    },
    PrechargeVoltageOK,
    DischargeVoltageOK,

    // Motor Controller
    MotorControllerSetupCommand,
    MotorControllerSetOperationalCommand,
    OpenPrechargeRelaysCommand,
    MotorControllerSetupComplete,
    MotorControllerOperational,

    // Relays
    ShutdownCircuitryRelayOpen,
    ShutdownCircuitryRelayClosed,
    BatteryPrechargeRelayOpen,
    BatteryPrechargeRelayClosed,
    MotorControllerRelayOpen,
    MotorControllerRelayClosed,
    DischargeRelayOpen,
    DischargeRelayClosed,

    // Navigation
    EndOfTrackBrake,

    // Dynamics
    UnclampBrakesCommand,
    ClampBrakesCommand,
    RetractLateralSuspensionCommand,
    ExtendLateralSuspensionCommand,

    BrakesClamped {
        from: Board,
    },
    BrakesUnclamped {
        from: Board,
    },
    LateralSuspensionRetracted {
        from: Board,
    },
    LateralSuspensionExtended {
        from: Board,
    },
    DynamicsStatus {
        from: Board,
        actuator_pressure_bar: Pressure,
    },

    // Propulsion
    StartPropulsionAccelerationCommand,
    StartPropulsionBrakingCommand,
    PropulsionAccelerationStarted,
    PropulsionBrakingStarted,

    PropulsionStatus {
        current_ma: Current,
        velocity_kmh: Velocity,
        temperature_c: Temperature,
        voltage_cv: Voltage,
    },
    PropulsionForce {
        force_n: Force, // calculated thrust force
    },
}

Communication with the base station

• MQTT_SEND and MQTT_RECEIVE: The rest of the board can send and see received messages by sending/subscribing them

State Machine Actions

Read this for what the telemetry board does with the state machine

Tasks

task	function
mqtt	Sends and Receives MQTT messages with rust_mqtt.
can_sender	Sends messages
can_receiver	Receives messages
can_to_mqtt	Sends CAN measurement messages as MQTT to the base station
emergency_handler	Shuts down the pod
send_heartbeat	Sends heartbeat to boards
heartbeat_monitor	Checks if all boards are responding to heartbeat messages in the acceptable latency
mqtt_to_event_bus	Checks for operator commands from the MQTT messages
event_to_can	Sends some event bus messages to can messages
read_imd	Reads readings from the IMD
base_station_heartbeat	Heartbeat with the basestation
run	Runs the state machine

Sensors used

sensor	pins	address	wiring_photo	type	extra_info
IMD & the CAN bus	PD0, PD1	-	-	CAN	-