Transport apparatus

A transport apparatus comprising:

• a plurality of transport containers, each transport container having a magnetic body;
• a transport plane on which the plurality of transport containers are transported;
• a plurality of magnetic poles that are arranged under the transport plane, each magnetic pole including a core and a coil;
• a drive unit that applies a voltage to the magnetic poles;
• and a calculation unit that controls the drive unit,
• wherein the drive unit detects a current that flows through the magnetic poles, and
• wherein the calculation unit is configured to:
• detect respective positions of the transport containers on the transport plane based on the detected currents, calculate respective transport speeds of the transport containers transported along a same route passing through a plurality of positions, based on the respective transport passing through each position on the transport plane and a time at which the respective transport container passes through each position and using an interval of time required for the transport containers to move between ones of the plurality of magnetic poles in an acceleration region where the respective transport containers accelerate from a first position to a second position, the transport speed being greatest at the second position among positions the transport container passes through, and a distance between the magnetic poles in the acceleration region,
• estimate a mass of each of the transport containers based on an average acceleration in the acceleration region of the transport containers,
• compare the calculated transport speed of the respective transport containers and a reference transport speed of a reference transport container having a predetermined mass, and
• detect a surface state of the transport plane based on a difference in the mass of the transport containers, and the respective comparisons of the transport speeds of the transport containers and the reference transport speed.