Motor drive system, motor control system, and self-propelled robot

A motor drive system comprising:

• a first motor unit having a first motor and a first processor to control the first motor;
• and
• a second motor unit having a second motor and a second processor to control the second motor,
• wherein
• the first motor unit and the second motor unit are connected together by a communication line,
• in a synchronization mode, the first processor sends data via the communication line at first time,
• in the synchronization mode, the second processor sends, via the communication line, information indicating second time at which the second processor receives the data and third time at which the second processor starts executing a task operating based on the data,
• in the synchronization mode, the first processor changes the first time to new first time obtained by delaying the first time by a period of time corresponding to a difference between the second time and the third time, based on previously stored information about an operating frequency of the second processor, and information indicating the second time and the third time, and
• in a normal operation mode after the synchronization mode, the first processor sends data via the communication line at regular intervals P1 from the new first time as a starting point, and the second processor receives the data at regular intervals P2 via the communication line and executes the task.

A motor control system comprising:

• a system controller having a first processor;
• and
• a motor unit having a motor and a second processor to control the motor,
• wherein
• the system controller and the motor unit are connected together by a communication line,
• the first processor sends data via the communication line at regular intervals P1,
• the second processor receives the data via the communication line at the regular intervals P1 from first time,
• the second processor executes a task operating based on the data at regular intervals P2 from second time as a starting point,
• in a synchronization mode, the second processor changes the second time to new second time that occurs within a predetermined allowable time from the first time, and
• in a normal operation mode after the synchronization mode, the first processor sends data via the communication line at the regular intervals P1, and the second processor executes the task operating based on the data at the regular intervals P2 from the new second time as a starting point.