Possible that some CANbus message are eaten?

S

Stéphane de Luca

I am developing a firmware update via CANbus 2.0B. The client is written in python to send the firmware binary file to the receiver (an esp32-based custom pcb equipped with a CANbus transceiver). The communication runs at 500kbps.

Simply put, the protocole I ended up with is as follows: the client opens the firmware file, read 8-byte chunk and transmits the chunk of the file, to the receiver, which keeps track of the chunk index, starting from 0 and incrementing. On the receiver, on chunk reception, the chunk is written to the flash via a RAM buffer. The receiver keeping track of the index on its side as well, it sends a message back (with a different arbitration id) that contains the index in the payload. So that the client can compare the receiver index with its own and potentially emit a transmission error if they mismatch. The file to transfer is about 1.4MB. The whole process takes about 8 minutes.

My messages use normal communication (aka not a listener nor a no-ack). It does not use CANbus filtering either.

That kind of handshake works nicely when the mac that bears an USB peak adapter which itsel is connected via two wires to the esp32 pcb can high/low connector.

Now, the receiver is actually a battery and the esp32 pcb set in its enclosure.

The battery is itself inserted in a transport robot. The battery communication port is connected to the comm port of the robot. That very CANbus port is located inside the chassis of the robot. But the robot has another CANbus port outside the chassis that is easily accessible.

So when I plug my peak to the « outside » port, and keep the robot turned off, the firmware update works nicely the same way it works in direct connection (aka straight to the battery), whilst I noticed a longer time to transfer (12 minutes).

Now, when the robot is turned on, the process stops working. It is kind of my messages are lost somewhere.

The CANbus communication itself seems to work: my client sees others standard messages coming from one of the robot devices. The robot itself has 3 devices connected to the CANbus. Those devices use 500kbps as well. From the 3 devices two use standard frames while the third uses extended frames.

The robot manufacturer says the bus is low loaded (around 5% of the maximum).

What would potentially be the source of the problem? What could I setup to better investigate the situation?
 

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UnityでPUN2を使用したMetaQuest3のMRマルチプレイでHeadとHandの位置がずれる問題について

私は現在、Unityを使用してMeta Quest 3向けのローカル空間で動作するMRマルチプレイヤーアプリケーションを開発しています。このアプリケーションではPUN2を通信手段として使用しており、プレイヤーのHeadとLeft Hand、Right Handを同期させたいと考えています。

問題点 アプリケーション内で、2つのHMD（Meta Quest 3）を使用してプレイした際、HeadとHandの位置が実際のユーザーの体の位置と大きくずれてしまいます。具体的には、HeadとHandのオブジェクトが、相手プレイヤーの体の位置に適切に重ならず、誤った位置に表示されてしまいます。

実現したいこと HeadとHandが、相手ユーザーの体の実際の位置に正確に重なるようにしたいです。現状では、ずれて表示されてしまっているため、これを解決する方法をご提案いただきたいです。

現在の設定

  • OVRCameraRigを使用してカメラを配置しています。
  • OVRSceneManagerおよびPassthrough機能を使用しています。

現在使用しているスクリプト
NetworkManager.cs

Code: 
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using Photon.Pun;
using Photon.Realtime;

public class NetworkManager : MonoBehaviourPunCallbacks
{
    void Start()
    {
        ConnectToServer();
    }

    void ConnectToServer()
    {
        PhotonNetwork.ConnectUsingSettings();
        Debug.Log("Connecting to server...");
    }

    public override void OnConnectedToMaster()
    {
        Debug.Log("Connected to server.");
        base.OnConnectedToMaster();
        RoomOptions roomOptions = new RoomOptions();
        roomOptions.MaxPlayers = 4;
        roomOptions.IsVisible = true;
        roomOptions.IsOpen = true;

        PhotonNetwork.JoinOrCreateRoom("Room 1", roomOptions, TypedLobby.Default);
    }

    public override void OnJoinedRoom()
    {
        Debug.Log("Joined room.");
        base.OnJoinedRoom();
    }

    public override void OnPlayerEnteredRoom(Player newPlayer)
    {
        Debug.Log("New player joined.");
        base.OnPlayerEnteredRoom(newPlayer);
    }
}

NetworkPlayerSpawner.cs

Code: 
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using Photon.Pun;

public class NetworkPlayerSpawner : MonoBehaviourPunCallbacks
{
    public GameObject spawnedPlayerPrefab;
    public override void OnJoinedRoom()
    {
        base.OnJoinedRoom();
        spawnedPlayerPrefab = PhotonNetwork.Instantiate("Network Player", transform.position, transform.rotation);
    }

    public override void OnLeftRoom()
    {
        base.OnLeftRoom();
        PhotonNetwork.Destroy(spawnedPlayerPrefab);
    }
}

NetworkPlayer.cs

Code: 
using UnityEngine;
using Photon.Pun;

public class NetworkPlayer : MonoBehaviour
{
    public Transform head;
    public Transform leftHand;
    public Transform rightHand;
    private PhotonView photonView;

    public Animator leftHandAnimator;
    public Animator rightHandAnimator;

    private Transform headRig;
    private Transform leftHandRig;
    private Transform rightHandRig;

    void Start()
    {
        photonView = GetComponent<PhotonView>();
        OVRCameraRig rig = FindObjectOfType<OVRCameraRig>();
        headRig = rig.centerEyeAnchor;
        leftHandRig = rig.leftHandAnchor;
        rightHandRig = rig.rightHandAnchor;

        if (photonView.IsMine)
        {
            foreach (var item in GetComponentsInChildren<Renderer>())
            {
                item.enabled = false;
            }
        }
    }

    void Update()
    {
        if (photonView.IsMine)
        {
            MapPosition(head, headRig);
            MapPosition(leftHand, leftHandRig);
            MapPosition(rightHand, rightHandRig);

            UpdateHandAnimation(OVRInput.Controller.LTouch, leftHandAnimator);
            UpdateHandAnimation(OVRInput.Controller.RTouch, rightHandAnimator);
        }
    }

    void UpdateHandAnimation(OVRInput.Controller controller, Animator handAnimator)
    {
        float triggerValue = OVRInput.Get(OVRInput.Axis1D.PrimaryIndexTrigger, controller);
        handAnimator.SetFloat("Trigger", triggerValue);

        float gripValue = OVRInput.Get(OVRInput.Axis1D.PrimaryHandTrigger, controller);
        handAnimator.SetFloat("Grip", gripValue);
    }

    void MapPosition(Transform target, Transform rigTransform)
    {
        target.position = rigTransform.position;
        target.rotation = rigTransform.rotation;
    }
}

試したこと 現在のところ、PUN2によるオブジェクトの同期は問題なく行われているようですが、HeadやHandの位置が適切にプレイヤーの体に重ならず、大きくずれてしまう状況です。具体的な原因や解決策がわからないため、アドバイスをいただけると助かります。

何か、HeadとHandの位置を正確にプレイヤーに重ねるためのアプローチがあれば、ぜひご教示ください。

よろしくお願いいたします。

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Есть словарь

array = {'string1':12.3, 'string2':0.4,......}

Требуется отсортировать по значениям. Значения float. Что я делаю:

Code: 
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TypeError: float() argument must be a string or a real number, not 'NoneType'

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is
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     v_report_row kol_dep;
     
     cursor c_dep
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 ```DECLARE
v_table pkg_agg_employees.kol_dep_tb;

BEGIN
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