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smt-optimizer/base_optimizer/optimizer_aggregation.py
2023-03-15 21:14:56 +08:00

221 lines
8.6 KiB
Python

from base_optimizer.optimizer_common import *
from ortools.sat.python import cp_model
from collections import defaultdict
@timer_wrapper
def optimizer_aggregation(component_data, pcb_data):
# === phase 0: data preparation ===
M = 1000 # a sufficient large number
a, b = 1, 6 # coefficient
K, I, J, L = max_head_index, 0, 0, 0 # the maximum number of heads, component types, nozzle types and batch level
component_list, nozzle_list = defaultdict(int), defaultdict(int)
cpidx_2_part, nzidx_2_nozzle = {}, {}
for _, data in pcb_data.iterrows():
part = data['part']
if part not in cpidx_2_part.values():
cpidx_2_part[len(cpidx_2_part)] = part
component_list[part] += 1
idx = component_data[component_data['part'] == part].index.tolist()[0]
nozzle = component_data.loc[idx]['nz']
if nozzle not in nzidx_2_nozzle.values():
nzidx_2_nozzle[len(nzidx_2_nozzle)] = nozzle
nozzle_list[nozzle] += 1
I, J = len(component_list.keys()), len(nozzle_list.keys())
L = I + 1
HC = [[M for _ in range(J)] for _ in range(I)] # the handing class when component i is handled by nozzle type j
# represent the nozzle-component compatibility
for i in range(I):
for _, item in enumerate(cpidx_2_part.items()):
index, part = item
cp_idx = component_data[component_data['part'] == part].index.tolist()[0]
nozzle = component_data.loc[cp_idx]['nz']
for j in range(J):
if nzidx_2_nozzle[j] == nozzle:
HC[index][j] = 0
# === phase 1: mathematical model solver ===
model = cp_model.CpModel()
solver = cp_model.CpSolver()
# === Decision Variables ===
# the number of components of type i that are placed by nozzle type j on placement head k
X = {}
for i in range(I):
for j in range(J):
for k in range(K):
X[i, j, k] = model.NewIntVar(0, component_list[cpidx_2_part[i]], 'X_{}_{}_{}'.format(i, j, k))
# the total number of nozzle changes on placement head k
N = {}
for k in range(K):
N[k] = model.NewIntVar(0, J, 'N_{}'.format(k))
# the largest workload of all placement heads
WL = model.NewIntVar(0, len(pcb_data), 'WL')
# whether batch Xijk is placed on level l
Z = {}
for i in range(I):
for j in range(J):
for l in range(L):
for k in range(K):
Z[i, j, l, k] = model.NewBoolVar('Z_{}_{}_{}_{}'.format(i, j, l, k))
# Dlk := 2 if a change of nozzles in the level l + 1 on placement head k
# Dlk := 1 if there are no batches placed on levels higher than l
D = {}
for l in range(L):
for k in range(K):
D[l, k] = model.NewIntVar(0, 2, 'D_{}_{}'.format(l, k))
D_abs = {}
for l in range(L):
for j in range(J):
for k in range(K):
D_abs[l, j, k] = model.NewIntVar(0, M, 'D_abs_{}_{}_{}'.format(l, j, k))
# == Objective function ===
model.Minimize(a * WL + b * sum(N[k] for k in range(K)))
# === Constraint ===
for i in range(I):
model.Add(sum(X[i, j, k] for j in range(J) for k in range(K)) == component_list[cpidx_2_part[i]])
for k in range(K):
model.Add(sum(X[i, j, k] for i in range(I) for j in range(J)) <= WL)
for i in range(I):
for j in range(J):
for k in range(K):
model.Add(X[i, j, k] <= M * sum(Z[i, j, l, k] for l in range(L)))
for i in range(I):
for j in range(J):
for k in range(K):
model.Add(sum(Z[i, j, l, k] for l in range(L)) <= 1)
for i in range(I):
for j in range(J):
for k in range(K):
model.Add(sum(Z[i, j, l, k] for l in range(L)) <= X[i, j, k])
for k in range(K):
for l in range(L - 1):
model.Add(sum(Z[i, j, l, k] for j in range(J) for i in range(I)) >= sum(
Z[i, j, l + 1, k] for j in range(J) for i in range(I)))
for l in range(I):
for k in range(K):
model.Add(sum(Z[i, j, l, k] for i in range(I) for j in range(J)) <= 1)
for l in range(L - 1):
for j in range(J):
for k in range(K):
model.AddAbsEquality(D_abs[l, j, k],
sum(Z[i, j, l, k] for i in range(I)) - sum(Z[i, j, l + 1, k] for i in range(I)))
for k in range(K):
for l in range(L):
model.Add(D[l, k] == sum(D_abs[l, j, k] for j in range(J)))
for k in range(K):
model.Add(N[k] == sum(D[l, k] for l in range(L)) - 1)
for l in range(L):
for k in range(K):
model.Add(0 >= sum(HC[i][j] * Z[i, j, l, k] for i in range(I) for j in range(J)))
# === Main Process ===
component_result, cycle_result = [], []
feeder_slot_result, placement_result, head_sequence = [], [], []
solver.parameters.max_time_in_seconds = 20.0
status = solver.Solve(model)
if status == cp_model.OPTIMAL or status == cp_model.FEASIBLE:
print('total cost = {}'.format(solver.ObjectiveValue()))
# convert cp model solution to standard output
model_cycle_result, model_component_result = [], []
for l in range(L):
model_component_result.append([None for _ in range(K)])
model_cycle_result.append([0 for _ in range(K)])
for k in range(K):
for i in range(I):
for j in range(J):
if solver.BooleanValue(Z[i, j, l, k]) != 0:
model_component_result[-1][k] = cpidx_2_part[i]
model_cycle_result[-1][k] = solver.Value(X[i, j, k])
# remove redundant term
if sum(model_cycle_result[-1]) == 0:
model_component_result.pop()
model_cycle_result.pop()
head_component_index = [0 for _ in range(max_head_index)]
while True:
head_cycle = []
for head, index in enumerate(head_component_index):
head_cycle.append(model_cycle_result[index][head])
if len([cycle for cycle in head_cycle if cycle > 0]) == 0:
break
component_result.append([None for _ in range(max_head_index)])
min_cycle = min([cycle for cycle in head_cycle if cycle > 0])
for head, index in enumerate(head_component_index):
if model_cycle_result[index][head] != 0:
component_result[-1][head] = model_component_result[index][head]
else:
continue
model_cycle_result[index][head] -= min_cycle
if model_cycle_result[index][head] == 0 and index + 1 < len(model_cycle_result):
head_component_index[head] += 1
cycle_result.append(min_cycle)
part_2_index = {}
for index, data in component_data.iterrows():
part_2_index[data['part']] = index
for cycle in range(len(component_result)):
for head in range(max_head_index):
part = component_result[cycle][head]
component_result[cycle][head] = -1 if part is None else part_2_index[part]
feeder_slot_result = feeder_assignment(component_data, pcb_data, component_result, cycle_result)
# === phase 2: heuristic method ===
mount_point_pos = defaultdict(list)
for pcb_idx, data in pcb_data.iterrows():
part = data['part']
part_index = component_data[component_data['part'] == part].index.tolist()[0]
mount_point_pos[part_index].append([data['x'], data['y'], pcb_idx])
for index_ in mount_point_pos.keys():
mount_point_pos[index_].sort(key=lambda x: (x[1], x[0]))
for cycle_idx, _ in enumerate(cycle_result):
for _ in range(cycle_result[cycle_idx]):
placement_result.append([-1 for _ in range(max_head_index)])
for head in range(max_head_index):
if component_result[cycle_idx][head] == -1:
continue
index_ = component_result[cycle_idx][head]
placement_result[-1][head] = mount_point_pos[index_][-1][2]
mount_point_pos[index_].pop()
head_sequence.append(dynamic_programming_cycle_path(pcb_data, placement_result[-1], feeder_slot_result[cycle_idx]))
else:
warnings.warn('No solution found!', UserWarning)
return component_result, cycle_result, feeder_slot_result, placement_result, head_sequence