test_goddard.jl: added abstract def

Author: jcaillau

test/old/test_goddard.jl

@@ -6,3 +6,57 @@ sol = solve(prob.model, grid_size=10, print_level=0, init=init)
 @testset verbose = true showtiming = true ":goddard :all_constraints" begin
     @test sol.objective ≈ prob.solution.objective rtol=1e-2
 end
+
+# goddard, abstract def
+const Cd = 310
+const Tmax = 3.5
+const β = 500
+const b = 2
+const t0 = 0
+r0 = 1
+v0 = 0
+vmax = 0.1
+m0 = 1
+mf = 0.6
+x0 = [ r0, v0, m0 ]
+
+@def ocp begin
+
+    tf, variable
+    t ∈ [ t0, tf ], time
+    x ∈ R³, state
+    u ∈ R, control
+    
+    r = x₁
+    v = x₂
+    m = x₃
+   
+    x(t0) == [ r0, v0, m0 ]
+    0  ≤ u(t) ≤ 1
+    r0 ≤ r(t) ≤ Inf,     (1)
+    0  ≤ v(t) ≤ vmax,    (2)
+    mf ≤ m(t) ≤ m0,      (3)
+
+    ẋ(t) == F0(x(t)) + u(t) * F1(x(t))
+ 
+    r(tf) → max
+    
+end
+
+F0(x) = begin
+    r, v, m = x
+    D = Cd * v^2 * exp(-β*(r - 1))
+    F = [ v, -D/m - 1/r^2, 0 ]
+    return F
+end
+
+F1(x) = begin
+    r, v, m = x
+    F = [ 0, Tmax/m, -b*Tmax ]
+    return F
+end
+
+sol = solve(ocp, grid_size=10, print_level=5)
+@testset verbose = true showtiming = true ":goddard :all_constraints" begin
+    @test sol.objective ≈ prob.solution.objective rtol=1e-2
+end