Moving body control device

Abstract

The present application relates to a mobile body control device. The mobile body control device controls a mobile body that moves by rotation of a motor. The mobile body control device includes a pinch detection unit that detects a pinch of an object based on a change in a physical quantity that indicates a rotational state of the motor. The pinch detection unit is configured to determine that a pinch has occurred in a case where a first difference in the physical quantity in a first period is equal to or greater than a first threshold value and a tendency of a change in the physical quantity in the first period is monotonously increasing or monotonously decreasing, and to reduce a value of the first threshold value in a case where the monotonously increasing or monotonously decreasing tendency of the physical quantity continues for a period longer than the first period.

Description

Technical Field

[0001] One or more embodiments of the present invention relate to a means for controlling a moving body, such as an electric seat equipped in a vehicle, and more particularly to a moving body control means having the function of detecting the clamping of foreign objects. Background Technology

[0002] Vehicles such as autonomous four-wheeled vehicles are equipped with electrically operated seats that move forward and backward by rotating an electric motor. In related technologies, adjusting the fore-and-aft position of such electrically operated seats involves manually operating a control unit located near the seat and moving the seat forward or backward. However, in recent years, vehicles have emerged that pre-register seat positions according to user preferences, recognize the user upon boarding, and automatically move the seat to the position corresponding to that user.

[0003] In vehicles equipped with the automatic seat position adjustment function described above, if the front seat automatically moves backward when a person or object is between the front and rear seats, the person or object may be trapped between the front and rear seats, threatening safety. The same situation can occur in manual or power seats. Therefore, the seat control device is required to have the function of quickly detecting a trapping situation, stopping or reversing the motor, and eliminating the trapping state if it occurs.

[0004] When clamping occurs, as the load applied to the motor increases, the current flowing through the motor increases, and the motor speed decreases. Therefore, by detecting the change (difference) in a physical quantity such as motor current or speed over a predetermined period and comparing the detected value with a threshold, it can be determined whether clamping has occurred. JP-A-2019-027247, JP-A-2005-290691, JP-A-2016-014292, and JP-A-2007-056620 disclose techniques for detecting clamping based on this change in physical quantities.

[0005] Incidentally, motor current increases with the load applied to the motor. Therefore, by calculating the change (difference) in motor current over a predetermined period and comparing this difference to a threshold, it is possible to determine whether clamping has occurred. However, since flexible cushioning materials are typically used in seats, there is a time lag between the occurrence of clamping and its detection. This will refer to... Figure 11 Describe it.

[0006] Figure 11This illustrates a situation where a passenger's leg F is trapped between the front seat S1 and the rear seat S2. This trapping occurs, for example, when seat S1 moves backward and seat S2 moves forward simultaneously. When the front seat S1 moves backward a distance d1 from its initial position (represented by a dashed line) to its current position (represented by a solid line), leg F is trapped between seat S1 and seat S2. Besides a person's leg, other objects such as a person's body, luggage, or animals can also be trapped.

[0007] However, because seat S1 is flexible, therefore... Figure 11 At the solid line position, the motor load is insufficient, and clamping is not detected. Subsequently, a depression forms in the seat S1 at the clamping portion indicated by K, and the seat S1 moves further back a distance d2 and stops at the position indicated by the dashed line. At this position, the motor load increases, the difference in motor current becomes equal to or greater than a threshold, and clamping is detected.

[0008] As mentioned above, in Figure 11 In the diagram, clamping cannot be detected at the solid line position where seat S1 has moved a distance of d1, but it can be detected at the dashed line position where seat S1 has moved a distance of d1+d2. Therefore, to accurately detect clamping, a long time period is needed to calculate the difference in motor current. However, while a longer calculation period makes it easier to detect clamping, it also increases the possibility of falsely detecting clamping due to interference.

[0009] Although the case of a flexible seat has been described herein, the same situation described above can occur even if the seat is rigid, when a soft object is clamped. JP-A-2007-131138 discloses a seat control device capable of properly detecting clamping when an object is clamped by a soft part of the seat. Furthermore, JP-A-2010-119210, JP-A-H08-149871, JP-A-H08-004416, JP-A-2001-248358, and JP-A-H07-158338 disclose an electric window device capable of accurately detecting the clamping of a soft object in a vehicle window.

[0010] On the other hand, if the front seat moves backward and impacts the legs of a passenger in the rear seat, the passenger may attempt to twist their lower body to avoid being trapped (hereinafter referred to as an "escaping operation"). This will be referred to in [reference needed]. Figure 12 Describe it.

[0011] Figure 12A schematic diagram illustrating a passenger seated in a seat, viewed from above, is shown. In the normal state (state XIIa), the leg F of passenger P, seated in the rear seat S2, is separated from the front seat S1. From this state, as shown in state XIIb, when the front seat S1 moves backward and impacts passenger P's leg F, as shown in state XIIc, passenger P quickly twists his / her lower body to avoid being trapped, and leg F tilts relative to seat S1. Then, as shown in state XIId, seat S1 moves further backward as leg F shifts, while still in contact with leg F, and leg F is trapped. Because seat S1 follows the shift of leg F, the motor load is insufficient and cannot operate as expected. Figure 11 That's how clamping is detected. Summary of the Invention

[0012] One or more embodiments of the present invention provide a moving body control device that can accurately detect clamping even when the moving body or object is soft or when performing an escape operation to avoid clamping.

[0013] A mobile body control device according to one or more embodiments of the present invention is a device for controlling a mobile body moved by the rotation of an electric motor. The mobile body control device includes: a clamping detection unit that detects clamping of an object caused by the movement of the mobile body based on changes in a physical quantity representing the rotational state of the electric motor; and a control unit that controls the operation of the electric motor based on the detection result of the clamping detection unit. The clamping detection unit is configured to determine that clamping of an object has occurred when a first difference in the physical quantity during a predetermined first time period is equal to or greater than a first threshold (first condition) and the trend of change of the physical quantity during the first time period is monotonically increasing or monotonically decreasing (second condition). Furthermore, the clamping detection unit is configured to decrease the value of the first threshold when the monotonically increasing or monotonically decreasing trend of the physical quantity persists for a period longer than the first time period.

[0014] In this way, for example, when held in a flexible seat, both the first and second conditions are met, and holding can be detected, while in the event of interference, the second condition is not met, thereby avoiding false identification of holding. Furthermore, even when performing an escape operation to attempt to avoid holding, holding can be detected by lowering the value of the first threshold.

[0015] In one or more embodiments of the present invention, if the physical quantity does not show a monotonically increasing or monotonically decreasing trend after the first threshold is reduced, the clamping detection unit can return the first threshold to its original value.

[0016] In one or more embodiments of the present invention, the clamping detection unit may calculate the difference between the physical quantity at the beginning of the first time period and the physical quantity at the end of the first time period as a first difference; may calculate the difference between the physical quantity at the beginning of the second time period and the physical quantity at the end of the second time period as each of the plurality of second time periods obtained by dividing the first time period; and may determine whether the trend of change of the physical quantity in the first time period is monotonically increasing or monotonically decreasing if the ratio of the second differences among the plurality of second differences that is equal to or greater than a second threshold is equal to or greater than a third threshold.

[0017] In one or more embodiments of the present invention, the first difference is represented by ΔI, the second difference by ΔIs(m), the first threshold by α, the second threshold by β, the third threshold by γ, and the number of ΔIs(m) equal to or greater than β among the M ΔIs(m) in the first time period is represented by N. The clamping detection unit can calculate the trend score SC by SC=N / M, which represents the trend of the change of the physical quantity in the first time period; and can determine that the clamping of the object has occurred if ΔI≥α and SC≥γ are satisfied.

[0018] In this case, the clamping detection unit can determine that the object has been clamped if the relationship between M and N is M=N and ΔI≥α and SC=1.

[0019] In one or more embodiments of the present invention, the physical quantity may be the current flowing through the motor or the rotational speed of the motor.

[0020] In one or more embodiments of the present invention, the movable body may be a vehicle seat or a vehicle window.

[0021] According to one or more embodiments of the invention, accurate detection of clamping can be provided even when the moving body or object is soft or when performing an escape operation to avoid clamping. Attached Figure Description

[0022] Figure 1 This is a block diagram of an electric seat system including a seat control device according to a first embodiment of the present invention; Figure 2A and Figure 2B This is a schematic diagram used to explain the principle of distinguishing between clamping and interference; Figure 3A and Figure 3B It is a graph used to illustrate current difference, trend difference, trend score and their thresholds; Figure 4 It is a graph used to illustrate the calculation methods for current difference and trend difference; Figure 5 It is a graph illustrating the changes in various trend differences; Figure 6 It is a graph illustrating the changes in motor current, current difference, and trend fraction under the presence of disturbance; Figure 7 It is a graph illustrating the changes in motor current, current difference, and trend fraction under normal conditions; Figure 8 It is a graph illustrating the changes in motor current, current difference, and trend fraction when an escape operation is performed; Figure 9 This is a graph illustrating the change in the current difference threshold when an escape operation is performed; Figure 10 This is a block diagram of an electric seat system including a seat control device according to a second embodiment of the present invention; Figure 11 This is an illustration of a state where the object is held in place by a flexible seat; and Figure 12 This is a diagram illustrating the clamping state caused by an escape operation. Detailed Implementation

[0023] In embodiments of the invention, numerous specific details have been set forth in order to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention can be practiced without these specific details. In other instances, well-known features have not been described in detail to avoid obscuring the invention.

[0024] In the following description, embodiments of the present invention will be illustrated with reference to the accompanying drawings. In the drawings, the same reference numerals are used to denote the same or corresponding parts. The following description will use a vehicle seat as an example, which is a movable body, and will describe the application of the present invention to a seat control device.

[0025] Figure 1 An example of a seat control device 50 according to a first embodiment of the present invention and an electric seat system 100 using the seat control device is illustrated. The electric seat system 100 is equipped in a vehicle such as an autonomous four-wheeled vehicle and includes a seat control device 50, an operating unit 5, a motor current detection unit 6, a motor speed detection unit 7, a motor 8, a sliding mechanism 9, and a seat 20. The seat 20 is an electric seat driven by the motor 8 and the sliding mechanism 9.

[0026] The operation unit 5 consists of switches and the like for manually operating the seat 20. The motor current detection unit 6 detects the motor current flowing through the motor 8. The motor speed detection unit 7 detects the rotational speed of the motor 8. The motor 8 is a motor used to move the seat 20 along direction a (forward / backward direction). The sliding mechanism 9 is connected to the motor 8 and the seat 20, converting the rotational motion of the motor 8 into linear motion and moving the seat 20 a predetermined distance along direction a.

[0027] The seat control device 50 includes a control unit 1, a motor drive unit 2, and a threshold storage unit 3. The control unit 1 is composed of a CPU, etc., and controls the overall operation of the seat control device 50.

[0028] The control unit 1 is equipped with a clamping detection unit 4. The function of this clamping detection unit 4 is actually implemented in software. The method for detecting clamping will be described in detail later. The motor drive unit 2 consists of circuitry that generates drive signals (e.g., PWM signals) to rotate the motor 8. The threshold storage unit 3 stores thresholds α, α', β, and γ used by the clamping detection unit 4 to determine whether clamping exists between the seats. These thresholds will be described in detail later.

[0029] Next, we will refer to Figure 2A and Figure 2B This describes the basic principle of clamping detection according to one or more embodiments of the present invention. Figure 2A Examples of changes in motor current and current difference when clamping occurs are given, and Figure 2B Examples of changes in motor current and current difference under conditions of disturbance are illustrated. The horizontal axis of each figure represents the count value of pulses output from the rotation sensor (not shown) attached to motor 8, and corresponds to the distance traveled by seat 20 (as described later). Figures 3A to 9 (Same). Although the motor current and current difference are actually as follows: Figure 3A and Figure 3B The fluctuations shown are subtle, but in Figure 2A and Figure 2B They are illustrated in a simplified manner.

[0030] exist Figure 2A In this diagram, time period T is the unit segment used for clamping determination, and the presence of clamping is determined based on the change in motor current within time period T. This time period T gradually moves to the right in the diagram over time, and each time it is determined whether clamping exists within time period T. Time period T corresponds to the "first time period" in one or more embodiments of the present invention.

[0031] Now, suppose that clamping occurs at the beginning time point n' of time period T, the load on motor 8 begins to increase from this time point, and the motor current increases accordingly. Furthermore, as the rate of increase of the motor current increases over time, the current difference, representing the change of the motor current at regular intervals, also increases. Therefore, the current difference ΔIa at the end time point n of time period T is equal to or greater than the current difference threshold α, which is the first condition used to determine clamping. However, only under this first condition, in situations such as... Figure 2B As shown, if interference occurs during time period T, and the current difference ΔIb at time point n is equal to or greater than the current difference threshold α, then even if interference occurs, clamping will be incorrectly determined to have occurred.

[0032] Therefore, in one or more embodiments of the present invention, such as Figure 2A As shown, under clamping conditions, the motor current monotonically increases during time period T, while... Figure 2B As shown, under disturbance conditions, the motor current does not monotonically increase during time period T. Therefore, focusing on the fact that the motor current does not monotonically increase (fluctuate) during time period T, the monotonically increasing current difference during time period T is used as the second condition for determining clamping. Then, if both the first and second conditions are satisfied, clamping is determined to have occurred.

[0033] Therefore, in Figure 2B In the case of the interference shown, since the first condition is met but the second condition is not, it is uncertain whether it is clamping, and erroneous determination can be avoided. Furthermore, in one or more embodiments of the present invention, the accuracy of clamping detection is improved by using the unique method described below to determine whether the change of the motor current in time period T is monotonically increasing.

[0034] Next, we will refer to Figures 3A to 5 This describes a specific method for clamping detection according to one or more embodiments of the present invention.

[0035] Figure 3A and Figure 3B It is a graph used to illustrate the parameters used to determine the clamping action. Figure 3A In the context, the motor current I, current difference ΔI, current difference threshold α, and time period T are related to... Figure 2A and Figure 2B The same as described herein. The current difference threshold α corresponds to the "first threshold" in one or more embodiments of the present invention. In addition to these, new parameters such as trend difference ΔIs(m), trend difference threshold β, trend fraction SC, and trend fraction threshold γ are used in one or more embodiments of the present invention.

[0036] The trend difference ΔIs(m) is calculated as multiple time periods obtained by dividing the time period T (in Figure 3A The example only illustrates the difference in motor current I between the start and end times of each time period W within a single time period W. (Refer to...) Figure 4 Describe the details.

[0037] exist Figure 4 In this process, time period T is divided into seven segments, and within this time period, multiple (here, six) segments W1 to W6 are set. These segments W1 to W6 correspond to the "second time period" in one or more embodiments of the present invention. The width of each segment W1 to W6 is the same, which is twice the segment width Z (W1 to W6 = 2Z). In addition, each segment in W1 to W6 is set to be shifted by Z. The trend difference ΔIs(m) is the general term of the six trend differences ΔIs(1) to ΔIs(6) calculated for each segment, and is calculated by the following equation.

[0038] ΔIs(m) = I(n - [m - 1] ×Z) - I(n - [m - 1] × Z - W) ... (1)

[0039] The trend difference ΔIs(1) is the trend difference in time period W1, and is calculated as the difference between the motor current (current at point c) at the start time (n-2Z) of time period W1 and the motor current (current at point a = I(n)) at the end time (n) of time period W1. That is, in the above equation (1), when m=1 and W=W1, the trend difference ΔIs(1) is expressed as the following equation.

[0040] ΔIs(1) = I(n) - I(n - W1)

[0041] The trend difference ΔIs(2) is the trend difference in time period W2, and is calculated as the difference between the motor current (current at point d) at the beginning time point (n-3Z) of time period W2 and the motor current (current at point b) at the end time point (nZ) of time period W2. That is, in the above equation (1), when m=2 and W=W2, the trend difference ΔIs(2) is expressed as the following equation.

[0042] ΔIs(2) = I(n - Z) - I(n - Z - W2)

[0043] The trend difference ΔIs(3) is the trend difference in time period W3, and is calculated as the difference between the motor current (current at point e) at the start time point (n-4Z) of time period W3 and the motor current (current at point c) at the end time point (n-2Z) of time period W3. That is, in the above equation (1), when m=3 and W=W3, the trend difference ΔIs(3) is expressed as the following equation.

[0044] ΔIs(3) = I(n - 2Z) - I(n - 2Z - W3)

[0045] The trend difference ΔIs(4) is the trend difference in time period W4, and is calculated as the difference between the motor current (current at point f) at the start time point (n-5Z) of time period W4 and the motor current (current at point d) at the end time point (n-3Z) of time period W4. That is, in the above equation (1), when m=4 and W=W4, the trend difference ΔIs(4) is expressed as the following equation.

[0046] ΔIs(4) = I(n - 3Z) - I(n - 3Z - W4)

[0047] The trend difference ΔIs(5) is the trend difference in time period W5, and is calculated as the difference between the motor current (current at point g) at the start time point (n-6Z) of time period W5 and the motor current (current at point e) at the end time point (n-4Z) of time period W5. That is, in the above equation (1), when m=5 and W=W5, the trend difference ΔIs(5) is expressed as the following equation.

[0048] ΔIs(5) = I(n - 4Z) - I(n - 4Z - W5)

[0049] The trend difference ΔIs(6) is the trend difference in time period W6, and is calculated as the difference between the motor current at the start time point (n') of time period W6 (current at point h = I(n')) and the motor current at the end time point (n-5Z) of time period W6 (current at point f). That is, in the above equation (1), when m=6 and W=W6, the trend difference ΔIs(6) is expressed as the following equation.

[0050] ΔIs(6) = I(n - 5Z) - I(n - 5Z - W6)

[0051] As mentioned above, when calculating the six trend differences ΔIs(1) to ΔIs(6) in time period T, in Figure 4 The time period T is shifted to the right by a predetermined amount, and in the new time period T after the shift, the six trend differences ΔIs(1) to ΔIs(6) are calculated in the same manner as above. Figure 3B The illustration shows the changing state of the trend difference ΔIs(m) calculated sequentially in this manner. The trend difference threshold β is a threshold set for this trend difference ΔIs(m), and corresponds to the "second threshold" in one or more embodiments of the present invention. Figure 5 In the curves Va to Vf, Figure 3BThe trend difference is shown as independent trend differences ΔIs(1) to ΔIs(6). Figure 5 In the middle, the scales on the vertical and horizontal axes are different. Figure 3B The scale in the middle.

[0052] By comparing each of the trend differences ΔIs(1) to ΔIs(6) with the trend difference threshold β, the changing trend of the motor current I in time period T can be determined. For example, as Figure 5 As shown, if all the trend differences ΔIs(1) to ΔIs(6) at time point n are equal to or greater than the threshold β, it indicates that the motor current I increases monotonically during time period T (ignoring small fluctuations in the current). On the other hand, for example, if the number of differences ΔIs(1) to ΔIs(6) that are equal to or greater than the threshold β is 3, and the number of differences that are less than the threshold β is 3, it indicates that the motor current I fluctuates during time period T.

[0053] Therefore, in one or more embodiments of the present invention, the trend score SC, calculated for each time period T based on the trend difference ΔIs(m), is used as a parameter representing the trend of the motor current I during the time period T. Among the M trend differences ΔIs(m) in the time period T, the number of ΔIs(m) that are equal to or greater than the threshold β, denoted by N, is calculated using the following equation.

[0054] SC = N / M ... (2)

[0055] Figure 3A The trend score threshold γ is a threshold set for the trend score SC, and corresponds to the "third threshold" in one or more of the present invention.

[0056] When all the trend differences ΔIs(1) to ΔIs(6) are equal to or greater than the threshold β, in equation (2) above, M=6 and N=6, such that the trend score SC is SC=1. On the other hand, when there are 3 trend differences equal to or greater than the threshold β, in equation (2) above, M=6 and N=3, such that the trend score SC is SC=0.5. Furthermore, when there are no trend differences equal to or greater than the threshold β, in equation (2) M=6 and N=0, such that the trend score SC is SC=0.

[0057] As mentioned above, the trend score SC falls within the range of 1 ≥ SC ≥ 0, and the closer SC is to 1, the stronger the monotonically increasing trend of the motor current I. Therefore, the trend score SC is compared with the trend score threshold γ, and if SC ≥ γ, then... Figure 2A As shown, the motor current monotonically increases during time period T, and can be considered to satisfy the second condition for clamping as described above. Figure 3AIn the example, at time point n, since the current difference ΔI is equal to or greater than the threshold α (ΔI≥α) and the trend score SC is equal to or greater than the trend score threshold γ (SC≥γ), it is determined that both the first and second conditions are met, and clamping occurs.

[0058] If clamping is detected, the control unit 1 eliminates the clamping state by stopping or reversing the motor 8 through the motor drive unit 2.

[0059] Figure 6 Examples illustrating the changes in motor current I, current difference ΔI, and trend fraction SC in the presence of disturbance are given. For instance, a disturbance occurs when a passenger sitting in a seat shakes their body, resulting in an increased load on the motor due to the seat. Figure 6 In the above scenario, the current difference ΔI exceeds the threshold α due to disturbance, but because the change in motor current I is not monotonically increasing, the trend fraction SC does not exceed the threshold γ. Therefore, although the first condition is met, the second condition is not met, and thus clamping will not be incorrectly determined even if the motor load increases.

[0060] Figure 7 An example is given illustrating the changes in motor current I, current difference ΔI, and trend fraction SC under normal conditions without clamping or interference. In this case, since the fluctuation of motor current I is small, the current difference ΔI does not exceed the threshold α. Furthermore, since motor current I does not monotonically increase over a long period, the trend fraction SC also does not exceed the threshold γ. Therefore, since neither the first nor the second condition is met, clamping is not detected.

[0061] As described above, in this embodiment, clamping is determined to have occurred when the current difference ΔI is equal to or greater than the current difference threshold α (first condition) and the trend score SC is equal to or greater than the trend score threshold γ (second condition). The trend score SC represents the trend of change of the motor current I in time period T, and the value of the trend score SC differs between the case of applied interference and the case of clamping. Therefore, in the case of interference, even if the first condition is met, the second condition is not met, and thus even if the motor current I fluctuates significantly due to interference, erroneous determination of clamping can be avoided. As a result, even if the time period T used to calculate the difference ΔI of the motor current I is set to be relatively long to ensure that clamping of the flexible seat 20 is detected, interference and clamping are clearly distinguished, and erroneous detection of clamping can be suppressed.

[0062] However, using only the above-mentioned criteria, in implementing... Figure 12 Even in the case of the "escape operation" shown, there is still a problem that the clamping cannot be reliably detected. This will be described below.

[0063] Figure 8 An example is given illustrating the changes in motor current I, current difference ΔI, and trend fraction SC during an escape operation. In this case, in Figure 12 In the middle, when passenger P tilts his leg F to avoid being pinched, seat S1 moves backward along with the movement of leg F, so that the reaction force received by seat S1 from leg F does not increase rapidly. Therefore, since the load applied to motor 8 does not increase rapidly, the motor current I... Figure 8 The increase in Q is gradual, as shown in the range. Consequently, the increase in current difference ΔI also becomes gradual.

[0064] exist Figure 8 In the example, during time period T, the motor current I tends to increase monotonically (ignoring small fluctuations in the current), and the trend fraction SC remains SC=γ, thus satisfying the second condition (SC≥γ) mentioned above. However, since the increase in current difference ΔI is relatively gradual, the current difference ΔI does not reach the threshold α during time period T, and therefore does not satisfy the first condition (ΔI≥α) mentioned above. Therefore, even if clamping occurs due to escape operation, clamping cannot be detected.

[0065] Therefore, in one or more embodiments of the present invention, when the second condition SC≥γ (i.e., the monotonically increasing trend of the motor current I lasts for a longer period than time period T), the value of the current difference threshold α used in the first condition is reduced. Thus, clamping due to escape operation can be detected.

[0066] Specifically, such as Figure 9 As shown, when the trend score SC is SC=γ for a period X from time t1 to time t2, the clamping detection unit 4 reduces the current difference threshold value at time t2 from α to α' (α>α'). Time t1 is the point in time when the trend score SC becomes SC=γ, and the period X is a longer period than the period T (X>T). When the current difference threshold decreases from α to α' at time t2, the current difference ΔI exceeds the threshold α', satisfying both the first condition (ΔI≥α') and the second condition (SC≥γ) at that time, and clamping is detected. Therefore, the motor 8 stops or reverses, and the clamping state is eliminated. After a period of time, when the trend score SC becomes γ>SC at time t3, the clamping detection unit 4 restores the current difference threshold from α' to the original value α.

[0067] In this manner, according to this embodiment, even when passenger P performs an escape maneuver to attempt to avoid being clamped, clamping can be detected by reducing the value of the current difference threshold α. The motor current I can exhibit a gradual increasing trend not only during the escape maneuver but also when the seat is flexible or when a soft object is clamped. Therefore, one or more embodiments of the present invention are also effective in this case.

[0068] Figure 10 An example is shown of a seat control device 60 according to a second embodiment of the present invention and an example of an electric seat system 200 using the seat control device. Figure 10 The system includes two clamping detection units 4a and 4b, two motor current detection units 6a and 6b, two motor speed detection units 7a and 7b, two motors 8a and 8b, and a tilting mechanism 10. Due to other configurations and... Figure 1 Those configurations are the same, therefore, the ones with... will be omitted. Figure 1 Explanation of repeated parts.

[0069] exist Figure 10 In the electric seat 20, the seat portion 20a moves along direction a via a first motor 8a and a sliding mechanism 9, and the backrest 20b of the seat 20 tilts in direction b via a second motor 8b and a tilting mechanism 10.

[0070] The first motor drive unit 2a and the second motor drive unit 2b drive the first motor 8a and the second motor 8b, respectively. The first motor current detection unit 6a and the second motor current detection unit 6b detect the motor current flowing through the first motor 8a and the second motor 8b, respectively. The first motor speed detection unit 7a and the second motor speed detection unit 7b detect the rotational speeds of the first motor 8a and the second motor 8b, respectively. The first clamping detection unit 4a detects the clamping of an object when the seat 20 moves in direction a based on the current detected by the first motor current detection unit 6a. The second clamping detection unit 4b detects the clamping of an object when the backrest 20b is tilted in direction b based on the current detected by the second motor current detection unit 6b.

[0071] Furthermore, in this second embodiment, based on the same principle as the first embodiment, the first clamping detection unit 4a detects clamping of an object caused by the movement of the seat 20, and the second clamping detection unit 4b detects clamping of an object caused by the tilting of the backrest 20b. Moreover, if either the clamping detection units 4a or 4b detects clamping, the first motor 8a or the second motor 8b is stopped or reversed by the motor drive units 2a and 2b, thereby controlling unit 1 to eliminate the clamping state.

[0072] In the second embodiment, the thresholds α, α', β and γ stored in the threshold storage unit 3 can be set separately for the first clamping detection unit 4a and the second clamping detection unit 4b, respectively.

[0073] In one or more embodiments of the present invention, various embodiments other than those described above may be employed.

[0074] For example, in Figure 9 In this process, the current difference threshold α decreases to α' in one stage, but it can also decrease in two stages. This means that when the state SC ≥ γ (a monotonically increasing trend) persists for a certain period, the current difference threshold decreases from α to α'. Then, when the state SC ≥ γ persists for an even longer period, the current difference threshold decreases from α' to α'' (α > α' > α''). Furthermore, the current difference threshold α can decrease in three or more stages.

[0075] Furthermore, in the above embodiments, an example of detecting clamping based on the motor current detected by the motor current detection units 6, 6a and 6b is given, but clamping can also be detected based on the frequency of the ripple contained in the motor current.

[0076] Furthermore, the physical quantity used for clamping detection is not limited to current and frequency, but can be the motor speed detected by motor speed detection units 7, 7a, and 7b. In this case, when clamping occurs, the motor speed decreases, and the speed difference is represented by... Figure 2A The trend of monotonically decreasing during the time period T.

[0077] In addition, when determining whether the current or rotational speed increases or decreases monotonically during time period T, other mathematical methods can be used to replace the above equations (1) and (2).

[0078] Furthermore, in the above embodiments, in Figure 1 and Figure 10 The example given is that the motor drive units 2, 2a and 2b are disposed in the seat control devices 50 and 60, but these motor drive units 2, 2a and 2b can be disposed outside the seat control devices 50 and 60.

[0079] In addition, Figure 1 and Figure 10 In this configuration, motors 8, 8a, and 8b are located outside the seat control units 50 and 60, but these motors 8, 8a, and 8b can also be located within the seat control units 50 and 60.

[0080] Furthermore, while the above embodiments provide an example of a seat control device installed in a vehicle, the present invention can also be applied to electric window devices that open and close windows via an electric motor, and can also be applied to movement control devices used in fields other than vehicles.

[0081] While one or more embodiments of the invention have been described with respect to a limited number of implementations, those skilled in the art who benefit from this disclosure will understand that other embodiments can be devised without departing from the scope of the invention disclosed herein. Therefore, the scope of the invention should be defined only by the appended claims.

[0082] Cross-reference of related applications

[0083] This application is based on and claims priority to Japanese Patent Application No. 2021-077488, filed on April 30, 2021, the entire contents of which are incorporated herein by reference.

Claims

1. A moving body control device, the moving body control device controlling a moving body that moves by the rotation of an electric motor, the moving body control device comprising: A clamping detection unit that detects the clamping of an object caused by the movement of the moving body based on changes in a physical quantity representing the rotational state of the motor. as well as A control unit controls the operation of the motor based on the detection results of the clamping detection unit. The clamping detection unit is configured as follows: The difference between the physical quantity at the beginning of the first time period and the physical quantity at the end of the first time period is calculated as the first difference; If the first difference in the first time period is equal to or greater than the first threshold and the physical quantity changes monotonically or monotonically during the first time period, it is determined that the clamping of the object has occurred; and If the trend of monotonically increasing or monotonically decreasing of the physical quantity persists for a period longer than the first time period, the value of the first threshold is reduced.

2. The moving body control device according to claim 1, wherein, If the physical quantity does not show a monotonically increasing or monotonically decreasing trend after the first threshold is reduced, the clamping detection unit returns the first threshold to its original value.

3. The moving body control device according to claim 1 or 2, wherein, The clamping detection unit is configured to: For each of the plurality of second time periods obtained by dividing the first time period, the difference between the physical quantity at the beginning of the second time period and the physical quantity at the end of the second time period is calculated as each of the plurality of second differences; and If the ratio of the second differences among the plurality of second differences that is equal to or greater than the second threshold is equal to or greater than the third threshold, it is determined that the trend of the change of the physical quantity in the first time period is monotonically increasing or monotonically decreasing.

4. The moving body control device according to claim 3, wherein, The first difference is represented by ΔI, the second difference by ΔIs(m), the first threshold by α, the second threshold by β, the third threshold by γ, and the number of ΔIs(m) equal to or greater than β among the M ΔIs(m) in the first time period by N. The clamping detection unit is configured to: The trend score SC is calculated using the following formula, whereby the trend score SC represents the trend of the change in the physical quantity during the first time period: SC=N / M, and The clamping of the object is determined to have occurred if ΔI≥α and SC≥γ are satisfied.

5. The moving body control device according to claim 4, wherein, The clamping detection unit determines that the clamping of the object has occurred when the relationship between M and N is M=N and ΔI≥α and SC=1.

6. The moving body control device according to claim 1 or 2, wherein, The physical quantity is the current flowing through the motor or the rotational speed of the motor.

7. The moving body control device according to claim 1 or 2, wherein, The moving body is a vehicle seat or window.

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