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For low cost, but well designed and well supported in linux, I can recommend the USB2CAN from 8Devices. If you will be booting windows occasionally to set up industrial drives or sensors, or doing real-time, stick with Peak or Kvasser. If you will be adding a real-time kernel underneath Linux, check the driver list to confirm support for what you are ...


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Use an oscilloscope. Place oscilloscope probes on an i/o line on the master and a motor phase line on the slave. Toggle the i/o line just before sending the can bus command for a step change in the motor control. Measure the time difference between i/o trigger and pwm step change. Blocking the motor so it's angle does not change makes it easier to see the ...


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In modern industrial motion control, the communication between the controller (motion controller, robot controller, CNC contoller) is typically done with: Profinet CanOpen Sercos EtherCAT


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First, you should define what real-time requirements do you have, not necessarily from a CAN-Bus, but from the application perspective. What is your cycle time, what latency can you accept, what jitter is acceptable by your application. If your requirements can be fulfilled by a PC with a CAN-Open extension, then you can use a ROS CanOpen package (like this) ...


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There are many possible routes you can take. You mentioned CAN. CANOpen is built on CAN and is used in many automation and robotics related devices. CANOpen specifies a SYNC mechanism exactly for the purpose you mention. More about this here. As for cycle times, the bandwidth and exact message size of CAN packets is knows, so cycle times are easy to ...


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CANopen is a application level protocol and socketcan is at the transport level. You can send Canopen messages using socketcan without any problems. You can compose canopen messages by hand but it will be a lot easier if you use a library


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candump can output the timestamp for each message in different formats. Check the usage notes of candump. candump -t d can0 will give you the time difference between messages for instance.


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Max Motor Speed is used to protect the motor against being driven over it's maximum speed. The units for this are RPM. Max Profile Velocity is given in same units as the profile velocity and applies only to profile position mode. (Source CiA DSP 402 V2.0) While the standard doesn't expand on these, the way I see it is that the first number is something ...


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scope probe I can sympathize with how frustrating it is when attaching an oscilloscope probe to debug a problem makes the system act differently. A standard 1X probe (1:1 probe) will load a circuit with a capacitance of about 110 pF. Many people use a 10X probe or a 100X probe, giving 1/10 or 1/100 the loading on the circuit -- hopefully small enough to be ...


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