We Claim:
1. An onboard system provided at a transport vehicle (CIO, CI OB) that is
elongated and travels along a previously provided route (RL1), the onboard system comprising
two control parts (10), wherein
each of the two control parts (10) has a function of performing a first process for controlling the travel of the transport vehicle (CIO, CI OB),
a first control part (10a) being one control part (10) out of the two control parts (10) is provided at a first end being one end of the transport vehicle (C10, CI 0B),
a second control part (10b) being other control part (10) out of the two control parts (10) is provided at a second end being other end of the transport vehicle (C10, CI 0B),
the second control part (10b) does not perform the first process in a period during which the first control part (10a) is performing the first process, and
the second control part (10b) performs a maintenance process for performing maintenance of the transport vehicle (C10, CI0B) in the period during which the first control part (10a) is performing the first process.
2. The onboard system according to claim 1, wherein
the maintenance process is a process of handling a plurality of types of data showing a state of the transport vehicle (C10, CI 0B),
with each of the plurality of types of data, a condition relating to the state of the transport vehicle (C10, CI0B) and a priority used when the condition is satisfied are associated, and

target data being one of the plurality of types of data is processed, when the condition associated with the target data is satisfied, according to the priority associated with the target data.
3. The onboard system according to one of claims 1 and 2, wherein the onboard
system switches, over the two control parts (10), between a control part to perform the
first process and a control part to perform the maintenance process.
4. The onboard system according to one of claims 1 to 3, further comprising:
a first apparatus (40Ca, 50Ca) provided at the first end; and
a second apparatus (40Cb, 50Cb) provided at the second end, wherein
each of the first apparatus (40Ca, 50Ca) and the second apparatus (40Cb, 50Cb) includes a maintenance part (11) having a function of performing the maintenance process,
each of the first apparatus (40Ca, 50Ca) and the second apparatus (40Cb, 50Cb) has, as an operation mode, a normal mode for performing a second process relating to the travel of the transport vehicle (CIO), and a standby mode where the performing the second process is not permitted,
when the operation mode of the first apparatus (40Ca, 50Ca) is the normal mode, the operation mode of the second apparatus (40Cb, 50Cb) is the standby mode,
when the operation mode of the second apparatus (40Cb, 50Cb) is the normal mode, the operation mode of the first apparatus (40Ca, 50Ca) is the standby mode, and
one of the first apparatus (40Ca, 50Ca) and the second apparatus (40Cb, 50Cb) whose operation mode is the standby mode performs the maintenance process.

5. The onboard system according to claim 4, wherein the onboard system switches,
over the first apparatus (40Ca, 50Ca) and the second apparatus (40Cb,50Cb), between an
apparatus to perform the second process and an apparatus to perform the maintenance
process.
6. The onboard system according to one of claims 1 and 2, comprising
four control parts (10) including the two control parts (10), wherein
the four control parts (10) are formed by two control parts (10) provided at the first end, and two control parts (10) provided at the second end,
each of the four control parts (10) has a function of performing the first process, and
the four control parts (10) are formed by:
a main control part being one control part (10) that performs the first process;
one control part (10) that performs the first process upon a failure of the main control part; and
two control parts (10) that perform the maintenance process in a period during which the main control part is performing the first process.
7. The onboard system according to claim 6, wherein the onboard system switches,
over the four control parts (10), between a control part to perform the first process and a
control part to perform the maintenance process.
8. The onboard system according to one of claims 6 and 7, further comprising:
a first apparatus (40Ca, 50Ca) provided at the first end; and

a second apparatus (40Cb, 50Cb) provided at the second end, wherein
each of the first apparatus (40Ca, 50Ca) and the second apparatus (40Cb, 50Cb) includes a maintenance part (11) having a function of performing the maintenance process,
each of the first apparatus (40Ca, 50Ca) and the second apparatus (40Cb, 50Cb) has, as an operation mode, a normal mode for performing a second process relating to the travel of the transport vehicle (CIO), and a standby mode where the performing the second process is not permitted,
when the operation mode of the first apparatus (40Ca, 50Ca) is the normal mode, the operation mode of the second apparatus (40Cb, 50Cb) is the standby mode,
when the operation mode of the second apparatus (40Cb, 50Cb) is the normal mode, the operation mode of the first apparatus (40Ca, 50Ca) is the standby mode, and
one of the first apparatus (40Ca, 50Ca) and the second apparatus (40Cb, 50Cb) whose operation mode is the standby mode performs the maintenance process.
9. The onboard system according to claim 8, wherein the onboard system switches,
over the first apparatus (40Ca, 50Ca) and the second apparatus (40Cb,50Cb), between an
apparatus to perform the second process and an apparatus to perform the maintenance
process.
10. The onboard system according to one of claims 1 and 2, comprising
four control parts (10) including the two control parts (10), wherein
the four control parts (10) are formed by two control parts (10) provided at the first end, and two control parts (10) provided at the second end,
each of the four control parts (10) has a function of performing the first process,

and
the four control parts (10) are formed by:
a main control part being one control part (10) that performs the first process;
two control parts (10) to perform the first process upon a failure of the main control part; and
one control part (10) that performs the maintenance process in a period during which the main control part is performing the first process.
11. The onboard system according to claim 10, wherein the onboard system
switches, over the four control parts (10), between a control part to perform the first
process and a control part to perform the maintenance process.
12. The onboard system according to one of claims 10 and 11, further comprising:
a first apparatus (40Ca, 50Ca) provided at the first end; and
a second apparatus (40Cb, 50Cb) provided at the second end, wherein
each of the first apparatus (40Ca, 50Ca) and the second apparatus (40Cb, 50Cb) includes a maintenance part (11) having the function of performing the maintenance process,
each of the first apparatus (40Ca, 50Ca) and the second apparatus (40Cb, 50Cb) has, as an operation mode, a normal mode for performing a second process relating to the travel of the transport vehicle (C10), and a standby mode where the performing the second process is not permitted,
when the operation mode of the first apparatus (40Ca, 50Ca) is the normal mode, the operation mode of the second apparatus (40Cb, 50Cb) is the standby mode,

when the operation mode of the second apparatus (40Cb, 50Cb) is the normal mode, the operation mode of the first apparatus (40Ca, 50Ca) is the standby mode, and
one of the first apparatus (40Ca, 50Ca) and the second apparatus (40Cb, 50Cb) whose operation mode is the standby mode performs the maintenance process.
13. The onboard system according to claim 12, wherein the onboard system switches, over the first apparatus (40Ca, 50Ca) and the second apparatus (40Cb,50Cb), between an apparatus to perform the second process and an apparatus to perform the maintenance process.
14. The onboard system according to one of claims 1 and 2, comprising
u(where u is a natural number of 4 or greater)-pieces of control parts (10) including the two control parts (10), wherein
each of the u-pieces of control parts (10) has a function of performing the first process,
the u-pieces of control parts (10) include:
a main control part being one control part (10) that performs the first process; and
three or more control parts (10) excluding the main control part from the u-pieces of control parts (10),
each of the three or more control parts (10) does not perform the first process in a period during which the main control part is performing the first process, and
the three or more control parts (10) perform a plurality of types of the maintenance process in a distributed manner in the period during which the main control part is performing the first process.

15. The onboard system according to claim 14, wherein
the onboard system has a function of communicating with a ground system (2000) provided on a ground,
the transport vehicle (CIOB) is formed by k(where k is a natural number of 2 or greater)-pieces of unit trains (C5) linearly coupled to each other, and
the k-pieces of unit trains (C5) includes a first unit train (C5a) and a second unit train (C5b) coupled to each other, the onboard system further comprising:
a first control unit (UtCa (Uta, Utb)) provided at the first unit train (C5a); and
a second control unit (UtCb (Uta, Utb)) provided at the second unit train (C5b), wherein
the first control unit (UtCa) retains state data representing a state of the second unit train (C5b), and
the first control unit (UtCa) transmits the state data to one of the ground system (2000) and the second control unit (UtCb) when the coupling between the first unit train (C5a) and the second unit train (C5b) is released.
16. The onboard system according to one of claims 14 and 15, further comprising:
a first apparatus (40Ca, 50Ca); and
a second apparatus (40Cb, 50Cb), wherein
each of the first apparatus (40Ca, 50Ca) and the second apparatus (40Cb, 50Cb) includes a maintenance part (11) having a function of performing the maintenance process,
each of the first apparatus (40Ca, 50Ca) and the second apparatus (40Cb, 50Cb) has, as an operation mode, a normal mode for performing a second process relating to the

travel of the transport vehicle (CIO), and a standby mode where the performing the second process is not permitted,
when the operation mode of the first apparatus (40Ca, 50Ca) is the normal mode, the operation mode of the second apparatus (40Cb, 50Cb) is the standby mode,
when the operation mode of the second apparatus (40Cb, 50Cb) is the normal mode, the operation mode of the first apparatus (40Ca, 50Ca) is the standby mode, and
one of the first apparatus (40Ca, 50Ca) and the second apparatus (40Cb, 50Cb) whose operation mode is the standby mode performs the maintenance process.
17. The onboard system according to claim 16, wherein the onboard system switches, over the first apparatus (40Ca, 50Ca) and the second apparatus (40Cb, 50Cb), between an apparatus to perform the second process and an apparatus to perform the maintenance process.
18. A transport vehicle maintenance method performed by an onboard system provided at a transport vehicle (CIO, CI OB) that is elongated and travels along a previously provided route (RL1), wherein
the onboard system includes two control parts (10),
each of the two control parts has a function of performing a first process for controlling the travel of the transport vehicle (CIO, CI OB),
a first control part (10a) being one control part (10) out of the two control parts (10) is provided at a first end being one end of the transport vehicle (CIO, CI OB),
a second control part (10b) being other control part (10) out of the two control parts (10) is provided at a second end being other end of the transport vehicle (C10, CI 0B),

the second control part (10b) does not perform the first process in a period during which the first control part (10a) is performing the first process, and
the transport vehicle maintenance method comprises a step (SI) in which the second control part (10b) performs a maintenance process for performing maintenance of the transport vehicle (CIO, CI OB) in the period during which the first control part (10a) is performing the first process.