diff --git a/src/all_building_blocks/spoilt_slice_selects.jl b/src/all_building_blocks/spoilt_slice_selects.jl
index b4830fd7ea60393ef7599beee461b7508d8a4bbc..6cbcceaff858aa82b70abc37563a1ec1f25599b7 100644
--- a/src/all_building_blocks/spoilt_slice_selects.jl
+++ b/src/all_building_blocks/spoilt_slice_selects.jl
@@ -4,7 +4,7 @@ import LinearAlgebra: norm
import StaticArrays: SVector
import JuMP: @constraint, @objective, objective_function
import ...BuildSequences: global_model, global_scanner
-import ...Variables: VariableType, duration, rise_time, flat_time, effective_time, qval, gradient_strength, slew_rate, inverse_slice_thickness, get_free_variable, get_pulse
+import ...Variables: VariableType, duration, rise_time, flat_time, effective_time, qval, gradient_strength, slew_rate, inverse_slice_thickness, get_free_variable, get_pulse, set_simple_constraints!
import ...Components: ChangingGradient, ConstantGradient, RFPulseComponent
import ..BaseBuildingBlocks: BaseBuildingBlock
@@ -35,26 +35,46 @@ struct SpoiltSliceSelect <: BaseBuildingBlock
slew_rate :: Number
end
-function SpoiltSliceSelect(pulse::RFPulseComponent; orientation=[0, 0, 1], group=nothing, spoiler_scale=nothing, kwargs...)
+function SpoiltSliceSelect(pulse::RFPulseComponent; orientation=[0, 0, 1], group=nothing, spoiler_scale=nothing, slice_thickness=nothing, kwargs...)
model = global_model()
- res = SpoiltSliceSelect(
- orientation ./ norm(orientation),
- get_free_variable(nothing; start=0.1),
- get_free_variable(nothing; start=0.1),
- get_free_variable(nothing; start=0.05),
- pulse,
- get_free_variable(nothing; start=0.1),
- get_free_variable(nothing; start=0.1),
- group,
- slew_rate(global_scanner()),
- )
- for time_var in (res.rise_time1, res.flat_time1, res.diff_time, res.flat_time2, res.fall_time2)
- @constraint model time_var >= 0
+ res = nothing
+ if isinf(slice_thickness)
+ rise_time_var = get_free_variable(nothing)
+ flat_time_var = get_free_variable(nothing)
+ res = SpoiltSliceSelect(
+ orientation ./ norm(orientation),
+ rise_time_var,
+ flat_time_var,
+ 0.,
+ pulse,
+ flat_time_var,
+ rise_time_var,
+ group,
+ slew_rate(global_scanner()),
+ )
+ for time_var in (rise_time, flat_time)
+ @constraint model time_var >= 0
+ end
+ else
+ res = SpoiltSliceSelect(
+ orientation ./ norm(orientation),
+ get_free_variable(nothing; start=0.1),
+ get_free_variable(nothing; start=0.1),
+ get_free_variable(nothing; start=0.05),
+ pulse,
+ get_free_variable(nothing; start=0.1),
+ get_free_variable(nothing; start=0.1),
+ group,
+ slew_rate(global_scanner()),
+ )
+ for time_var in (res.rise_time1, res.flat_time1, res.diff_time, res.flat_time2, res.fall_time2)
+ @constraint model time_var >= 0
+ end
+ @constraint model res.diff_time <= res.rise_time1
+ @constraint model res.diff_time <= res.fall_time2
+ @constraint model qval(res, nothing, 1) == qval(res, 1, nothing)
end
- @constraint model res.diff_time <= res.rise_time1
- @constraint model res.diff_time <= res.fall_time2
- @constraint model qval(res, nothing, 1) == qval(res, 1, nothing)
if !isnothing(spoiler_scale)
if spoiler_scale == :min # note that spoiler_scale is inverse of qval
@objective model Min objective_function(model) - qval(res, nothing, 1)
diff --git a/src/helper_functions.jl b/src/helper_functions.jl
index d475012bd6a592d07c8298555734ac50f5f6e53c..cf1a0d6bee08f3e254c84330d5815b32e0f5e112 100644
--- a/src/helper_functions.jl
+++ b/src/helper_functions.jl
@@ -96,8 +96,9 @@ For an [`InstantPulse`](@ref) (i.e., `shape=:instant`), only the `flip_angle`, `
- `spoiler`: set to the spatial scale on which the spins should be dephased in mm. For rotating spoilers, this does include the contribution from the slice select gradient as well.
- `rotate_grad`: name of the parameter with which the slice selection and spoiler gradient will be rotated after sequence optimisation (default: `:FOV`).
- `scanner`: overrides the [`global_scanner`](@ref) for this part of the sequence. Recommended to set only if not part of a larger sequence.
+- `orientation`: vector with orientation of slice select gradient and pulses (defaults: z-direction).
"""
-function refocus_pulse(; flip_angle=180, phase=0., frequency=0., shape=:sinc, slice_thickness=Inf, Nzeros=3, group=nothing, rotate_grad=:FOV, bandwidth=nothing, duration=nothing, spoiler=Inf, scanner=nothing, optimise=false)
+function refocus_pulse(; flip_angle=180, phase=0., frequency=0., shape=:sinc, slice_thickness=Inf, Nzeros=3, group=nothing, bandwidth=nothing, duration=nothing, spoiler=Inf, scanner=nothing, optimise=false, orientation=[0, 0, 1])
build_sequence(scanner; optimise=optimise) do
pulse = _get_pulse(shape, flip_angle, phase, frequency, Nzeros, group, bandwidth, duration)
if pulse isa InstantPulse && !isinf(slice_thickness)
@@ -107,18 +108,11 @@ function refocus_pulse(; flip_angle=180, phase=0., frequency=0., shape=:sinc, sl
if isinf(slice_thickness)
return pulse
else
- return Trapezoid(pulse=pulse, duration=:min, slice_thickness=[Inf, Inf, slice_thickness], orientation=[0, 0, 1.], rotate=rotate_grad)
+ return SliceSelect(pulse=pulse, duration=:min, slice_thickness=slice_thickness, orientation=orientation, group=:FOV)
end
else
- orientation=isnothing(rotate_grad) ? [1, 1, 1] : [0, 0, 1]
- if isinf(slice_thickness)
- grad = Trapezoid(orientation=orientation, duration=:min, rotate=rotate_grad)
- @constraint global_model() qvec(grad)[3] == 2Ï€ * 1e-3 / spoiler
- return Sequence(grad, pulse, grad; TR=Inf)
- else
- res = SpoiltSliceSelect(pulse; orientation=orientation, duration=:min, rotate=rotate_grad, slice_thickness=slice_thickness, spoiler_scale=spoiler)
- return res
- end
+ res = SpoiltSliceSelect(pulse; orientation=orientation, duration=:min, group=:FOV, slice_thickness=slice_thickness, spoiler_scale=spoiler)
+ return res
end
end
end