Supported Sensors

Panasonic US24

panasonic-us24
V2.0.8-pr.8
CAN
410

Supported hardware versions

Manufacturer Panasonic
Hardware model US24

Sensor background and requirements

Panasonic’s short range ultrasonic sensors provide critical object location data for obstacles within 150cm of the vehicle. By providing ranging information, these sensors can detect obstacles ranging from walls, to other vehicles and are a critical aid in parking.

Hardware requirements

  • Power and data harness, typically provided by OEM or reseller
    • CAN High/Low signals should be wired to DB9 pins 72 respectfully, with a terminating 120 Ohm resistor
  • 12V power supply
  • CAN interface on the ECU, compatible with linuxcan or socketcan hardware drivers
  • ECU with PolySync Core installed

Configuring the ECU

The ECUs CAN network needs to be configured to use one of the two compatible CAN interfaces: Kvaser’s linuxcan or socketcan.

Setup the CAN interfaces on the ECU to enable the driver to communicate with the sensor.

Configuring the PolySync driver

Adding the sensor to the SDF

Using the Configurator tool, add a sensor node to the SDF.

The ‘Node Interface’ name is panasonic-us24.

CAN Hardware and Circuit Identifiers

Each CAN interface on the ECU has a unique identifier that enables software applications like the PolySync Core driver to identify and connect to the appropriate CAN channel.

Locate the CAN hardware and circuit identifiers based on the CAN drivers installed on your system.

Enter the CAN Channel 0 Hardware Identifier and CAN Channel 0 Circuit Identifier in the Configurator.

CAN channels

Validating the sensor is properly configured

If you’re approaching a new PolySync system or need to validate an existing configuration you can use the following checklist to ensure the sensor is properly configured.

Setup checklist

If the sensor passes these checks then the PolySync dynamic driver will be able to communicate with the sensor.

  • The sensor is powered with 12V
  • The CAN bus is terminated with a 120 Ohm resistor
  • The PolySync Core driver is able to parse the sensor identifier

Starting the PolySync driver

The configuration set in the Configurator is loaded from the SDF when the dynamic driver starts. It connects to the sensor over the CAN interface, requests the data, and waits for confirmation that the sensor configuration is valid.

When the dynamic driver receives the first full frame of data it begins processing the data, abstracting the data from the OEM data structure in a high-level hardware agnostic message type. In this case the data is placed in a ps_zones_msg.

  1. Power the sensor and ECU on
  2. Optionally follow the setup checklist
  3. Start the PolySync Core manager
    • $ sudo service polysync-core-manager start
  4. Start the dynamic driver process

Starting the node manually on the command line

To start a dynamic driver node on the command line, the node must first be defined in the SDF using the Configurator application.

Each node defined in the Configurator has a unique node ID which points to the nodes configuration. This article explains how to find the node ID.

Command line flags and usage

Once the node ID is known (substitute for X), the dynamic driver node for the supported sensor can be started with the base command:

$ polysync-core-dynamic-driver -n X

Each sensor supports an array of command line arguments. To see a full list of command line arguments, pass the -h help flag:

$ polysync-core-dynamic-driver -n X -h  |  less

There’s a lot of output so we recommend you pipe the output to less, but it’s not required.

Flag Required Description Arguments
-c No use provided CAN channel system index instead of what is stored in the SDF
-d No enable additional debugging output
-e No Export a JSON support string describing the interface, used by the SDF configuration tool
-h No Show this help message
-i No Use provided PAL interface file instead of what is stored in the SDF
-n No SDF node configuration key for the node [required]
-o No Enable output of log messages to stdout (in addition to syslog)
-O No check the node SDF configuration for required updates and exit option (returns exit status zero if no change required)
-p No use provided logfile in Record and Replay operations instead of the default
-s No use provided SDF instead of the default
-t No Perform a validation test on the CAN interface
-u No allow updates to the SDF configuration during the normal runtime if needed (does not exit)
-U No update the node SDF configuration and exit
-w No Disable the hardware interface(s), allowing the node to run without hardware connected
DTC codes and common fixes
DTC value DTC name Fault description Notes
304 DTC_NOINTERFACE Interface not available Activated when the sensor is not reachable at the IP address set in the Configurator; activated when the sensor becomes unreachable during runtime

Accessing sensor data

When the dynamic driver node is operating in an OK state then data is being published to the global PolySync bus, and any node can subscribe to the high-level message type(s) output by the dynamic driver node.

There are several tools that PolySync provides to quickly validate that data exists on the bus.

Access sensor data with PolySync nodes that subscribe to the sensor’s output message types.

Input / output message types

Message API Docs Notes
Publishes ps_zones_msg Sensor Data Model Published to the bus by default. A zone representing the nearest obstacle
Publishes ps_can_frame_msg Core Data Model Publishing is disabled by default, the message buffer contains the raw data received from the sensor over the CAN bus

Enable and disable the publishing of specific message types in the Configurator.

Filtering incoming data for this sensor

An application that subscribes to a given message type is able to see data from more than one sensor or source.

Applications can filter for specific sensors and data sources in the message callback in C applications, or the messageEvent in C++ applications.

Filter incoming messages for this sensor with ps_sensor_kind value 410.

You can find all sensor descriptor values in this article.