使用 >= 约束抛出 RuntimeError（请使用 pydrake.common.containers.EqualToDict）

Question

我正在尝试使用直接转录来解决涉及一些三角函数的轨迹优化问题。

我有以下变量类型

a[i] = array([<Expression "(state_0(0) + 0.001 * state_0(4))">,
       <Expression "(state_0(1) + 0.001 * state_0(5))">,
       <Expression "(state_0(2) + 0.001 * state_0(6))">,
       <Expression "(state_0(3) + 0.001 * state_0(7))">,
       <Expression "...omitted...">,
       <Expression "...omitted...">,
       <Expression "...omitted...">,
       <Expression "...omitted...">], dtype=object)

b[i] = array([Variable('state_1(0)', Continuous),
       Variable('state_1(1)', Continuous),
       Variable('state_1(2)', Continuous),
       Variable('state_1(3)', Continuous),
       Variable('state_1(4)', Continuous),
       Variable('state_1(5)', Continuous),
       Variable('state_1(6)', Continuous),
       Variable('state_1(7)', Continuous)], dtype=object)

我正在尝试创建如下约束

mp.AddConstraint(b[i] <= a[i])

但是我得到以下错误

RuntimeError: You should not call `__bool__` / `__nonzero__` on `Formula`. If you are trying to make a map with `Variable`, `Expression`, or `Polynomial` as keys (and then access the map in Python), please use pydrake.common.containers.EqualToDict`.

Answer 1

似乎必须为每个元素指定约束，即

for j in range(8):
    mp.AddConstraint(b[i][j] <= a[i][j])

Answer 2

没错。尽管您也可以使用 eq(a,b) 这样的函数名称 https://github.com/RobotLocomotion/drake/issues/8315

使用 >= 约束抛出 RuntimeError（请使用 pydrake.common.containers.EqualToDict）

Using >= for constraint throws RuntimeError (please use pydrake.common.containers.EqualToDict)

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