Wiper control device
A wiper control device includes an acquisition unit and an estimation unit. The estimation unit is configured to acquire a value related to a current flowing through a wiper motor that drives a wiper configured to reciprocate between a first position and a second position. The estimation unit is configured to estimate a wiper angle, which is a rotation angle of the wiper, based on a current ripple in the current flowing through the wiper motor. The current ripple has a periodicity corresponding to driving of the wiper motor.
1 . A wiper control device comprising:
an acquisition unit configured to acquire a value related to a current flowing through a wiper motor that drives a wiper configured to reciprocate between a first position and a second position; and
an estimation unit configured to estimate a wiper angle, which is a rotation angle of the wiper, based on a current ripple in the current flowing through the wiper motor, the current ripple having a periodicity corresponding to driving of the wiper motor, wherein
the estimation unit is configured to estimate the wiper angle based on a number of times that an absolute value of an amount of change in the current flowing through the wiper motor becomes equal to or greater than a threshold value.
2 . The wiper control device according to claim 1 , wherein
the estimation unit is configured to change the threshold value in accordance with a change in a voltage of the wiper motor.
3 . The wiper control device according to claim 1 , wherein
the estimation unit is configured to change the threshold value in accordance with a change in a temperature of the wiper motor.
4 . The wiper control device according to claim 1 , wherein
the estimation unit is configured to change the threshold value in accordance with a change in a torque of the wiper motor.
5 . The wiper control device according to claim 1 , further comprising:
a current detection unit configured to detect the current flowing through the wiper motor; and
a switching unit configured to switch a detection range of the current detected by the current detection unit, wherein
the switching unit is configured to switch the detection range in such a manner that the detection range when the current flowing through the wiper motor is equal to or greater than a protection threshold value is larger than the detection range when the current flowing through the wiper motor is less than the protection threshold value.
6 . The wiper control device according to claim 1 , further comprising:
a current detection unit configured to detect the current flowing through the wiper motor; and
a switching unit configured to switch a detection range of the current detected by the current detection unit, wherein
the switching unit is configured to switch the detection range between a first detection range and a second detection range over time, and
the second detection range is smaller than the first detection range.
7 . A wiper control device comprising:
an acquisition unit configured to acquire a value related to a current flowing through a wiper motor that drives a wiper configured to reciprocate between a first position and a second position; and
an estimation unit configured to estimate a wiper angle, which is a rotation angle of the wiper, based on a current ripple in the current flowing through the wiper motor, the current ripple having a periodicity corresponding to driving of the wiper motor, wherein
the estimation unit is configured to estimate the wiper angle based on a number of times that the current flowing through the wiper motor changes from being less than a threshold value to being equal to or greater than the threshold value.
8 . The wiper control device according to claim 7 , wherein
the estimation unit is configured to change the threshold value in accordance with a change in a voltage of the wiper motor.
9 . The wiper control device according to claim 7 , wherein
the estimation unit is configured to change the threshold value in accordance with a change in a temperature of the wiper motor.
10 . The wiper control device according to claim 7 , wherein
the estimation unit is configured to change the threshold value in accordance with a change in a torque of the wiper motor.
11 . The wiper control device according to claim 7 , further comprising:
a current detection unit configured to detect the current flowing through the wiper motor; and
a switching unit configured to switch a detection range of the current detected by the current detection unit, wherein
the switching unit is configured to switch the detection range in such a manner that the detection range when the current flowing through the wiper motor is equal to or greater than a protection threshold value is larger than the detection range when the current flowing through the wiper motor is less than the protection threshold value.
12 . The wiper control device according to claim 7 , further comprising:
a current detection unit configured to detect the current flowing through the wiper motor; and
a switching unit configured to switch a detection range of the current detected by the current detection unit, wherein
the switching unit is configured to switch the detection range between a first detection range and a second detection range over time, and
the second detection range is smaller than the first detection range.
13 . A wiper control device comprising:
an acquisition unit configured to acquire a value related to a current flowing through a wiper motor that drives a wiper configured to reciprocate between a first position and a second position; and
an estimation unit configured to estimate a wiper angle, which is a rotation angle of the wiper, based on a current ripple in the current flowing through the wiper motor, the current ripple having a periodicity corresponding to driving of the wiper motor, wherein
the estimation unit is configured to estimate the wiper angle based on a number of times that the current flowing through the wiper motor changes from being greater than a threshold value to being equal to or less than the threshold value.
14 . The wiper control device according to claim 13 , wherein
the estimation unit is configured to change the threshold value in accordance with a change in a voltage of the wiper motor.
15 . The wiper control device according to claim 13 , wherein
the estimation unit is configured to change the threshold value in accordance with a change in a temperature of the wiper motor.
16 . The wiper control device according to claim 13 , wherein
the estimation unit is configured to change the threshold value in accordance with a change in a torque of the wiper motor.
17 . The wiper control device according to claim 13 , further comprising:
a current detection unit configured to detect the current flowing through the wiper motor; and
a switching unit configured to switch a detection range of the current detected by the current detection unit, wherein
the switching unit is configured to switch the detection range in such a manner that the detection range when the current flowing through the wiper motor is equal to or greater than a protection threshold value is larger than the detection range when the current flowing through the wiper motor is less than the protection threshold value.
18 . The wiper control device according to claim 13 , further comprising:
a current detection unit configured to detect the current flowing through the wiper motor; and
a switching unit configured to switch a detection range of the current detected by the current detection unit, wherein
the switching unit is configured to switch the detection range between a first detection range and a second detection range over time, and
the second detection range is smaller than the first detection range.