Remote interface unit position and interface allocation optimization method based on multiple constraints

Abstract

The invention belongs to the technical field of aircraft system design, and particularly relates to a remote interface unit position and interface allocation optimization method based on multiple constraints. The aircraft remote unit installation position and interface allocation optimization method comprises the following steps: defining external conditions at least comprising sensor and actuator position arrangement, remote interface unit interface type and number determination and an installation prohibition area; remote loads are eliminated, and adverse effects of individual remote loads on global optimization are prevented; randomly initializing the RIU position; and the RIU position is subjected to rolling optimization until the average distance of two continuous rounds of remote interface unit position changes is smaller than a threshold value, and a final optimization result is output. According to the method, under the condition of considering multiple constraints, the installation position and the interface distribution of the remote interface unit are optimized by taking the shortest length of the cable of the whole system as a target. After the length of the cable is reduced, the acquisition precision of the sensor is improved, and the weight of the aircraft cable is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of aircraft system design, and particularly relates to an optimization method for the position and interface allocation of a remote interface unit based on multiple constraints. Background Art

[0002] The advanced aircraft electromechanical management system adopts a three-level hybrid distributed control structure. According to the idea of accessing nearby, regional control, and centralized management, it comprehensively manages and controls the sensors and actuators of the electromechanical system. In this architecture, the remote interface unit (hereinafter referred to as RIU), as a key controller of the electromechanical system, communicates with the VMC through the on-board bus, and controls and collects loads such as regulating valves, valves, and sensors distributed throughout the aircraft. The remote interface unit has many cross-linked finished products, and the cross-linked electrical cables are widely distributed. The cables related to the RIU account for about 15% - 20% of the weight of the low-frequency cables on the aircraft. Optimizing the installation position of the RIU on the aircraft and the allocation of cross-linked interfaces can reduce the total cable length, which is of great significance in improving the sensor acquisition accuracy, implementing the regional control concept, and reducing the weight of the aircraft cables.

[0003] The optimization of the RIU installation position and interface allocation is subject to multiple constraints such as interface capacity limitations and installation bay limitations. At the same time, the installation positions of some on-board finished products are remote, which may cause extreme distribution of the RIU position and have an adverse impact on the overall system performance. Currently, the RIU installation position is completely dependent on manual experience allocation, and quantitative optimization design cannot be achieved. Therefore, it is necessary to propose an optimization method for the position and interface allocation of the remote interface unit considering multiple constraints. Summary of the Invention

[0004] The object of the present invention: To propose an optimization method for the installation position and interface allocation of an aircraft remote unit, replace the manual experience allocation, minimize the total length of the cross-linked cables of the remote interface unit, and thus achieve beneficial effects such as improving the sensor acquisition accuracy, thoroughly implementing the regional control design concept, and reducing the weight of the aircraft cables.

[0005] The technical solution of the present invention: To achieve the above object of the invention, the present invention provides an optimization method for the installation position and interface allocation of an aircraft remote unit, and the optimization method for the installation position and interface allocation of the aircraft remote unit includes the following steps:

[0006] The first step is to define external conditions, including at least the layout of the sensor and actuator positions, the determination of the types and quantities of the remote interface unit interfaces, and the prohibited installation areas;

[0007] The second step is to eliminate remote loads to prevent adverse effects of individual remote loads on the global optimization;

[0008] The third step is to randomly initialize the RIU position;

[0009] Step 4: Optimize the position of the RIU by rolling until the average distance △ of the position change of the remote interface unit in two consecutive rounds is less than the threshold, and then output the final optimization result.

[0010] Further, in Step 1, when arranging the positions of the sensors and actuators, determine the types, quantities, and installation positions of the sensors and actuators required for each system according to the system design and pipeline layout of the aircraft fuel, environmental control, power supply, hydraulic, and other systems.

[0011] Further, when determining the types and quantities of the remote interface unit interfaces, it includes: counting the types and total quantities of all sensors required for the entire system, and the total number of interfaces of the remote interface unit should be 1.3 - 1.5 times the total number of system interfaces.

[0012] Further, when defining the prohibited installation area:

[0013] Define the areas where the aircraft fuel tank, engine compartment, and other environmental characteristics do not meet the RIU installation conditions as prohibited installation areas;

[0014] For simplicity, simplify the prohibited installation area into a cuboid area or a combination of multiple cuboid areas; each cuboid area is expressed as:

[0015] |x min ,x max | = |y min ,y max | × |z min ,z max |;

[0016] Wherein, define the aircraft heading as the X-axis direction, the vertical direction as the Z-axis direction, and the lateral direction as the Y-axis direction. x min ,x max respectively represent the front and rear boundaries of the prohibited installation area in the X-axis direction; y min ,y max respectively represent the left and right boundaries of the prohibited installation area in the Y-axis direction, and z min ,z max respectively represent the upper and lower boundaries of the prohibited installation area in the Z-axis direction.

[0017] Further, after defining the external conditions, pre-position the remote interface unit, and place the RIU evenly distributed throughout the aircraft according to the aircraft geometry.

[0018] Further, when removing the edge loads, follow the following principles:

[0019] 1). For each load, calculate its Euclidean distance to other loads and sort them in ascending order of distance;

[0020] 2) For each load, find the loads whose distances to it rank from the m-th to the n-th (a total of n - m, simply referred to as the m~n nearest neighbors), and calculate the average distance between this load and the m~n nearest neighbors (simply referred to as the average nearest neighbor distance);

[0021] 3) If the average nearest neighbor distance of a certain load is greater than the threshold Θ, then this load is considered a remote load;

[0022] 4) Remote loads do not participate in iterative optimization. After other loads are optimized, they are manually allocated;

[0023] 5) The value of m should be selected as the maximum number of interfaces of a single finished product in the system, and the value of n should be selected as 2 to 4 times the average number of interfaces of a single finished product in the system. This selection method can effectively prevent the formation of nearest neighbors among multiple interfaces of a single finished product and can improve the recognition rate of remote loads;

[0024] 6) The value of Θ should be the upper quartile of the average nearest neighbor distance of all loads plus 1.5 times the interquartile range.

[0025] Furthermore, during rolling optimization, load allocation considering interface capacity limits is carried out in the vicinity, and at the same time, prohibited installation areas are also considered.

[0026] Furthermore, for load allocation considering interface capacity limits, the allocation principle is as follows:

[0027] 1) Calculate the distance between each load and all RIUs, and allocate it to the nearest RIU;

[0028] 2) Whenever a load is allocated to a certain RIU, the remaining available capacity of the corresponding interface type of the RIU should be reduced by 1;

[0029] 3) When the remaining available capacity of a certain type of interface of the RIU is less than 30%, subsequent loads cannot be allocated to this RIU, but should be allocated to the second nearest RIU, which can leave enough margin for the subsequent aircraft optimization design and retrofit;

[0030] 4) Specifically, for a load using a combined interface, when it is allocated to a certain RIU, the available capacities of multiple interfaces of this RIU should all be reduced;

[0031] 5) Repeat the process of 1)~4) for all loads until all loads are allocated to RIUs.

[0032] Furthermore, reposition the RIU positions according to the minimization of the Euclidean distance. The specific process is as follows:

[0033] For each RIU, denoted as R j , calculate the geometric center of the loads allocated to it according to the following formula, and update the position of the RIU after this round of iteration to:

[0034]

[0035] Where: T i is the i-th load assigned to the current RIU, T j is the set of loads assigned to R j , N is the sum of the number of pins of all loads assigned to R j , n is the sum of the number of pins included in the load T i , x i , y i , z i are the position coordinates of T i respectively, is the new RIU position coordinate generated in this round of iteration.

[0036] Furthermore, when trimming the position of the prohibited area, check whether the RIU falls into the prohibited installation area. If the RIU falls into the prohibited installation area, move it to the nearest boundary.

[0037] Furthermore, until the average distance △ of the position change of the remote interface unit in two consecutive rounds is less than the threshold value. The threshold value can be taken as 1% - 3% of the total length of the aircraft. The convergence criterion can be dynamically adjusted according to the length to flexibly adapt to different types of aircraft;

[0038] The formula for solving the average distance △ is as follows:

[0039]

[0040] Among them, K is the total number of RIUs of the aircraft, is the RIU position coordinate generated in the previous round.

[0041] The beneficial effects of the present invention: The present invention is used for the optimization design of the interface allocation of the aircraft electromechanical system. Considering multiple constraints, with the goal of minimizing the total length of the system cables, the installation positions and interface allocations of the remote interface units are optimized. After reducing the cable length, it helps to improve the sensor acquisition accuracy and reduce the cable weight of the aircraft. Compared with the prior art, it has the following advantages:

[0042] 1. Compared with relying on manual experience to complete the selection of RIU positions and interface allocations, the present invention can obtain the optimal RIU position and interface allocation scheme, realize the minimization of the cable length, and achieve the effects of improving the acquisition and control accuracy and reducing the cable weight;

[0043] 2. Compared with relying on manual experience to complete the selection of RIU positions and interface allocations, the present invention can avoid the interface capacity of the remote interface unit not exceeding the limit, and avoid the cumbersome process of repeatedly adjusting the interface due to insufficient RIU interface margin during manual allocation. Description of the Drawings

[0044] Figure 1 It is the flowchart of the working process of the remote interface unit location optimization method;

[0045] Figure 2 It is the schematic diagram of the principle of remote load rejection;

[0046] Figure 3 It is the schematic diagram of the process of load proximity allocation and repositioning of the RIU location. Specific implementation manners

[0047] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0048] Taking the RIU design of a certain type of aircraft as an example, according to the design idea of the remote interface unit location and interface allocation optimization method with multiple constraints proposed by the present invention, it is assumed that the system includes N loads and K RIUs. Each load (T i )(i = 1, 2,..., N) has a determined three-dimensional coordinate position (x i , y i , z i ). The final position of the remote interface unit (S j )(j = 1, 2,..., K) needs to be determined through optimization. Each of the three types of interfaces of each remote interface unit has a capacity limit (indicating the maximum number of connectable loads of the three types of interfaces). At the same time, it is required that the RIU cannot be installed in the fuel tank, and the fuel tank can be approximated as a cuboid region:

[0049] |x min , x max | × |y min , y max | × |z min , z max |

[0050] The optimization goal is to minimize the sum of the Euclidean distances from all loads to the corresponding RIUs:

[0051]

[0052] Among them, z ij .d(T i , S j ) represents the Euclidean distance when the load T i is assigned to the RIUS i .

[0053] 1. After completing the determination of the load position, the RIU interface and quantity, and the definition of the prohibited area, perform the initial allocation of the RIU positions to generate the initial positions of the RIUs:

[0054] ((x 0 1 , y 0 1 , z 0 1 )),(x 1 1 , y 1 1 , z 1 1 ),…,(x k 1 , y k 1 , z k 1 ))

[0055] where the subscript represents the number of the 0th to kth RIU, and the superscript represents the 1st iteration this time.

[0056] 2. Subsequently, perform outlier removal. As Figure 2 shown, taking the load in the figure as an example, this load and 4 nearby loads belong to the same finished product, and their distances to other loads are relatively far. For this load, take the loads whose distances to it are ranked 5th to 10th, then the m to n nearest neighbors circled by the shaded area in the figure are obtained. Calculate the average distance between the example load and the m to n nearest neighbors, and it can be found that this average distance is significantly greater than the average distance of the m to n nearest neighbors of other loads. Through this method, remote loads can be effectively removed to prevent them from having an adverse impact on the overall allocation.

[0057] In particular, since this load is very close to 4 nearby loads, if the common outlier detection algorithm is used to only detect the average distance between a certain load and several nearby loads, the average distance of the nearest neighbors of the example load in the figure is also very small, so it is impossible to identify this load as an outlier.

[0058] Using the m to n nearest neighbors to prevent the loads on the same finished product from spontaneously forming clusters and affecting outlier identification is a feature of the present invention that differentiates it from traditional algorithms.

[0059] 3. After completing the outlier removal, perform the RIU position allocation and trimming.

[0060] As Figure 3 shown, calculate the distance between each load and all RIUs, and allocate it to the nearest RIU.

[0061] When the remaining available capacity of a certain type of interface of the RIU is less than 30%, the subsequent load cannot be allocated to this RIU, but should be allocated to the next nearest RIU. After completing one round of allocation, the load circled by the dotted line in the figure is allocated to RIU1 (the initial RIU position).

[0062] Obviously, the initial RIU position cannot make its distance to all loads the shortest. Therefore, it is necessary to relocate the RIU to the geometric center of these loads:

[0063]

[0064] After locating to the geometric center, verify whether the relocated RIU position falls within the prohibited installation area. If the RIU coordinate position meets the following formula, it indicates that it is within the prohibited installation area.

[0065] (x j >x min &x j <x max )||(y j >y min &y j <y max )||(z j >z min &z j <z max )

[0066] If the RIU falls within the prohibited installation area, adjust the RIU position according to the following strategy:

[0067] If (x j ∈[x min ,x max ), adjust the X-direction coordinate to:

[0068]

[0069] The Y and Z directions are also adjusted using the same strategy.

[0070] 4. Iterate repeatedly until the RIU position converges:

[0071] Repeat step 3 and calculate the average position change of the RIU between two rounds:

[0072]

[0073] If the average position change is less than 1% of the total length of the aircraft, it is considered that the optimization is completed and the optimal RIU position and interface allocation are obtained; otherwise, continue to repeat step 3 for iteration.

[0074] The above are only specific embodiments of the present invention. The present invention has been described in detail, and the unelaborated parts are conventional technologies. However, the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention. The protection scope of the present invention shall be subject to the protection scope of the claims described above.

Claims

1. A method for optimizing remote interface unit location and interface allocation based on multiple constraints, characterized in that: The method for optimizing the installation position and interface allocation of aircraft remote units comprises the following steps: The first step is to define external conditions, including at least the location and layout of sensors and actuators, the type and quantity of interfaces of the remote interface unit, and prohibited installation areas; The second step is to eliminate remote loads to prevent individual remote loads from adversely affecting global optimization; Step 3: Randomly initialize the RIU position; Step 4: Rollingly optimize the RIU position until the average distance △ of the remote interface unit position change in two consecutive rounds is less than the threshold, and then output the final optimization result.

2. A method for optimizing remote interface unit location and interface allocation based on multiple constraints as claimed in claim 1, characterized in that: In the first step, the positions of sensors and actuators are arranged according to the system design and pipeline layout of the aircraft fuel, environmental control, power supply, hydraulic and other systems to determine the type, quantity and installation location of sensors and actuators required for each system.

3. A method for optimizing remote interface unit location and interface allocation based on multiple constraints as claimed in claim 2, characterized in that: When determining the types and number of interfaces of the remote interface unit, include: counting the types and total number of all sensors required for the entire system; the total number of interfaces of the remote interface unit should be 1.3 to 1.5 times the total number of interfaces of the entire system.

4. The method for optimizing remote interface unit location and interface allocation based on multiple constraints as claimed in claim 2, wherein when the installation area is prohibited from being defined: Aircraft fuel tanks, engine compartments and other areas where environmental characteristics do not meet RIU installation conditions are defined as prohibited installation areas; For the sake of simplicity, the prohibited installation area is simplified to a rectangular area, or a combination of multiple rectangular areas; each rectangular area is expressed as: |x min ,x max |×|y min ,y max |×|z min ,z max |; in, Define the aircraft heading as the X-axis direction, the vertical direction as the Z-axis direction, and the lateral direction as the Y-axis direction. min , x max They represent the front and rear boundaries of the prohibited installation area in the X-axis direction; y min ,y max They represent the left and right boundaries of the prohibited installation area in the Y-axis direction, min , z max They represent the upper and lower boundaries of the prohibited installation area in the Z-axis direction respectively.

5. A method for optimizing remote interface unit position and interface allocation based on multiple constraints as described in claim 1, wherein the remote interface units are pre-positioned after defining external conditions, and the RIUs are evenly distributed and placed throughout the aircraft according to the aircraft geometry.

6. The method for optimizing remote interface unit location and interface allocation based on multiple constraints as claimed in claim 1, wherein when removing edge loads, the following principles are followed: 1) For each load, calculate the Euclidean distance from it to other loads and sort them from smallest to largest; 2) For each load, find the loads ranked from the mth to the nth, a total of mn, referred to as m~n nearest neighbors, and calculate the average distance between this load and the m~n nearest neighbors, referred to as the average proximity distance; 3) If the average proximity distance of a load is greater than the threshold Θ, the load is considered to be a remote load; 4) Remote loads do not participate in iterative optimization and are manually assigned after other loads are optimized; 5) The value of m should be the maximum number of interfaces of a single finished product in the system, and the value of n should be 2 to 4 times the average number of interfaces of a single finished product in the system. This selection method can effectively avoid the formation of close neighbors between multiple interfaces of a single finished product, and can improve the recognition rate of remote loads; 6) The value of Θ should be the upper quartile of the average proximity distance of all loads plus 1.5 times the interquartile range.

7. A remote interface unit location and interface allocation optimization method based on multiple constraints as described in claim 6, during rolling optimization, the load distribution is considered to be close to the interface capacity limit, and the prohibited installation area is also considered.

8. A method for optimizing remote interface unit location and interface allocation based on multiple constraints as claimed in claim 7, wherein the load is allocated nearby considering the interface capacity limitation, and the allocation principle is as follows: 1) Calculate the distance between each load and all RIUs and assign it to the RIU closest to it; 2) Whenever a load is allocated to a certain RIU, the remaining available capacity of the corresponding interface type of the RIU shall be reduced by 1; 3) When the remaining available capacity of a certain type of interface of an RIU is less than 30%, the subsequent load cannot be allocated to this RIU, but should be allocated to the next closest RIU, which can leave enough margin for subsequent aircraft optimization design and modification; 4) In particular, for loads using combined interfaces, when they are assigned to a certain RIU, the available capacities of the various interfaces of the RIU will be reduced; 5) Repeat the process from 1) to 4) for all loads until all loads are allocated to RIU.

9. A method for optimizing remote interface unit position and interface allocation based on multiple constraints as claimed in claim 7, wherein the RIU position is relocated according to the minimized Euclidean distance, and the specific process is as follows: For each RIU, denoted as R j , calculate the geometric center of the assigned load according to the following formula, and update the RIU position after this round of iteration to: Where: T i is the i-th load assigned to the current RIU, T j Assigned to R j The load set, N is the load allocated to R j The total number of pins of all loads, n is the load T i The total number of pins included, x i ,y i ,z i T i The location coordinates, The new RIU position coordinates generated for this iteration.

10. A method for optimizing remote interface unit location and interface allocation based on multiple constraints as claimed in claim 9, characterized in that: When rolling optimization of RIU position, iterate repeatedly until the average distance △ of the remote interface unit position change in two consecutive rounds is less than the threshold. The threshold can be 1% to 3% of the total length of the aircraft. The convergence criterion can be dynamically adjusted according to the length to flexibly adapt to different types of aircraft. The formula for solving the average distance △ is as follows: Where K is the total number of aircraft RIUs, The RIU position coordinates generated in the previous round.

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