{"id":11700,"date":"2025-10-21T11:17:22","date_gmt":"2025-10-21T10:17:22","guid":{"rendered":"https:\/\/dronesonen.usn.no\/?p=11700"},"modified":"2025-11-07T12:44:56","modified_gmt":"2025-11-07T11:44:56","slug":"minimuck-week-9","status":"publish","type":"post","link":"https:\/\/dronesonen.usn.no\/?p=11700","title":{"rendered":"MiniMuck \u2013 Week 9"},"content":{"rendered":"\n

Hello W\u00f8rld! <\/p>\n\n\n\n

This week the team made a lot of progress. We got the Dynamixel servos running, completed the controller for the MVP, made progress with slam, and did a whole lot of CAD, 3D printing, and laser cutting.<\/p>\n\n\n\n

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Herman<\/h2>\n\n\n\n

This I have worked with the Dynamixel servos, and together with Ask to make the mechanical structure for our vehicle.<\/p>\n\n\n\n

Dynamixel Servo and Microcontroller<\/strong><\/p>\n\n\n\n

We have borrowed the Dynamixel XM430-210W-T from the University, which is a 210-degreee servo with about 4.0Nm stall- torque, which should be sufficient to drive the arms. With these, we have borrowed the OpenCM 9.04 microcontroller module with TTL interface, which can be programmed with the Arduino IDE by using the board file and Dynamixel2Arduino library.<\/p>\n\n\n\n

Setup Guide for Dynamixel:<\/em><\/strong><\/p>\n\n\n\n

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  1. Install board on Arduino IDE\n
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    1. Add to board paths: https:\/\/raw.githubusercontent.com\/ROBOTIS-GIT\/OpenCM9.04\/master\/arduino\/opencm_release\/package_opencm9.04_index.json<\/a><\/li>\n\n\n\n
    2. Install OpenCM 9.04 in board manager<\/li>\n<\/ol>\n<\/li>\n\n\n\n
    3. Run dxl-monitor from examples: OpenCM 9.04 \u2192 Dynamixel SDK \u2192 Protocol2.0 \u2192 dxl_monitor. Use the commands through the Serial monitor to configure the servos<\/li>\n\n\n\n
    4. Scan for servos using scan to see what unique addresses are present. Servos who have the same id only show up once, and must be connected one at a time to be configured individually.<\/li>\n<\/ol>\n\n\n\n
      [CMD] scan\nScan Dynamixel Using Protocol 1.0\n.............................................................\n\nScan Dynamixel Using Protocol 2.0\n \n               ... SUCCESS  [ID:001] Model No : 01030\n \n               ... SUCCESS  [ID:002] Model No : 01030\n.............................................................<\/code><\/pre>\n\n\n\n
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      1. Reset using rst2 001<\/code><\/strong><\/li>\n\n\n\n
      2. Set new unique ID on each servo on address 7 using w2 001 007 [ID]<\/strong><\/code> e.g. w2 001 007 002<\/strong><\/code>. It is best for only one servo to be connected simultaneously. Only disconnect the servo when power is shut off and the USB is disconnected from the PC!<\/li>\n\n\n\n
      3. Enable torque on address 64 using w2 001 064 1<\/strong><\/code><\/li>\n\n\n\n
      4. Servo is in position mode by default. Set position (dword) on addresses 116 through 119 using wrd2 001 116 [pos(0-4095)]<\/strong><\/code> If the servo moves to its new position, it is working.<\/li>\n<\/ol>\n\n\n\n
        When scanning, one servo did not show. First, I was unsure if the servo was functioning properly, but after some trial and error, I found that when the baud was set to 1M, the servo was visible, meaning it was only configured differently than the standard. To find this in dxl-monitor, I used baud 1M<\/code><\/strong>.<\/p>\n\n\n\n
        To fix this:<\/p>\n\n\n\n
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        1. Write to baud address in EEPROM using dxl-monitor: w2 002 008 1<\/strong><\/code><\/li>\n\n\n\n
        2. Remember to change back to baud 57600<\/strong><\/code><\/li>\n<\/ol>\n\n\n\n
          Now we are sure the servos are working properly and can be controlled with the Arduino2Dynamixel Library.<\/p>\n\n\n\n
          Using the example code, I tested the library, but got this error:<\/p>\n\n\n\n
          Error: Torque off failed\nError: Set operating mode failed\nError: Torque on failed<\/mark>\nLED ON\nGoal Position : 512\nLED OFF\nGoal Position : 2048\nLED ON<\/code><\/pre>\n\n\n\n
          After some troubleshooting, I found the issue. The code was expecting the expansion card to be connected, which uses another pin on the microcontroller. By changing these lines, the issue was fixed:<\/p>\n\n\n\n