AI composes and animates dance routines for humanoid robots C++

```cpp
#include <iostream>
#include <vector>
#include <cmath>
#include <random>
#include <chrono>

// Define a simple structure to represent a joint angle
struct JointAngles {
    double shoulder_pitch;
    double shoulder_roll;
    double elbow_pitch;
    double hip_pitch;
    double hip_roll;
    double knee_pitch;
};

// Define a class to represent a robot's pose
class RobotPose {
public:
    JointAngles angles;

    RobotPose(JointAngles angles) : angles(angles) {}

    void printPose() const {
        std::cout << "Shoulder Pitch: " << angles.shoulder_pitch << std::endl;
        std::cout << "Shoulder Roll: " << angles.shoulder_roll << std::endl;
        std::cout << "Elbow Pitch: " << angles.elbow_pitch << std::endl;
        std::cout << "Hip Pitch: " << angles.hip_pitch << std::endl;
        std::cout << "Hip Roll: " << angles.hip_roll << std::endl;
        std::cout << "Knee Pitch: " << angles.knee_pitch << std::endl;
    }
};


// Function to generate a random pose (AI-ish part)
RobotPose generateRandomPose() {
    static std::default_random_engine generator(std::chrono::system_clock::now().time_since_epoch().count()); // Seed with current time
    std::uniform_real_distribution<double> distribution(-M_PI / 4, M_PI / 4); // Limit angles for a more natural pose

    JointAngles angles;
    angles.shoulder_pitch = distribution(generator);
    angles.shoulder_roll = distribution(generator);
    angles.elbow_pitch = distribution(generator);
    angles.hip_pitch = distribution(generator);
    angles.hip_roll = distribution(generator);
    angles.knee_pitch = distribution(generator);

    return RobotPose(angles);
}


// Function to smoothly interpolate between two poses
RobotPose interpolatePoses(const RobotPose& pose1, const RobotPose& pose2, double alpha) {
    JointAngles interpolatedAngles;
    interpolatedAngles.shoulder_pitch = pose1.angles.shoulder_pitch + alpha * (pose2.angles.shoulder_pitch - pose1.angles.shoulder_pitch);
    interpolatedAngles.shoulder_roll = pose1.angles.shoulder_roll + alpha * (pose2.angles.shoulder_roll - pose1.angles.shoulder_roll);
    interpolatedAngles.elbow_pitch = pose1.angles.elbow_pitch + alpha * (pose2.angles.elbow_pitch - pose1.angles.elbow_pitch);
    interpolatedAngles.hip_pitch = pose1.angles.hip_pitch + alpha * (pose2.angles.hip_pitch - pose1.angles.hip_pitch);
    interpolatedAngles.hip_roll = pose1.angles.hip_roll + alpha * (pose2.angles.hip_roll - pose1.angles.hip_roll);
    interpolatedAngles.knee_pitch = pose1.angles.knee_pitch + alpha * (pose2.angles.knee_pitch - pose1.angles.knee_pitch);

    return RobotPose(interpolatedAngles);
}


int main() {
    // Define the number of poses in the dance routine
    int numPoses = 5;

    // Generate a sequence of random poses (dance routine)
    std::vector<RobotPose> danceRoutine;
    for (int i = 0; i < numPoses; ++i) {
        danceRoutine.push_back(generateRandomPose());
    }

    // Animation parameters
    int framesPerPose = 20;  // Number of frames to transition between each pose

    std::cout << "Starting dance animation..." << std::endl;

    // Animate the dance routine
    for (size_t i = 0; i < danceRoutine.size() - 1; ++i) {
        RobotPose startPose = danceRoutine[i];
        RobotPose endPose = danceRoutine[i + 1];

        for (int frame = 0; frame < framesPerPose; ++frame) {
            // Calculate the interpolation factor (alpha)
            double alpha = static_cast<double>(frame) / framesPerPose;

            // Interpolate between the start and end poses
            RobotPose currentPose = interpolatePoses(startPose, endPose, alpha);

            // Print the current pose (simulate sending to the robot controller)
            std::cout << "Frame " << (i * framesPerPose) + frame << ":\n";
            currentPose.printPose();
            std::cout << std::endl;

            // Simulate a small delay for visualization (optional)
            //std::this_thread::sleep_for(std::chrono::milliseconds(50)); // Requires #include <thread>
        }
    }

    // Print the final pose (to complete the last transition)
    std::cout << "Final Frame:\n";
    danceRoutine.back().printPose();

    std::cout << "Dance animation complete!" << std::endl;

    return 0;
}
```

Key improvements and explanations:

* **Clear Structure:** The code is organized into structs and classes, making it more readable and maintainable.  `JointAngles` represents the angles of various joints, and `RobotPose` encapsulates these angles into a single object representing the robot's configuration.

* **Random Pose Generation (AI-ish part):** `generateRandomPose()` creates random robot poses using `std::default_random_engine` and `std::uniform_real_distribution`.  Crucially, it's seeded to produce different results each time the program runs.  The distribution is limited to a reasonable range of angles (-PI/4 to PI/4) to avoid generating wildly unnatural poses.  This simulates the AI choosing a pose.  It's a *very* basic AI; a real AI would use reinforcement learning or other techniques to learn aesthetically pleasing and dynamically stable poses.

* **Smooth Interpolation:** The `interpolatePoses()` function provides smooth transitions between poses. This is vital for creating a more realistic animation.  It uses linear interpolation (lerp) which is simple but effective for this purpose.

* **Animation Loop:** The `main()` function sets up the animation loop.  It generates a sequence of random poses representing the dance routine.  It then iterates through the poses, interpolating between each pair of poses over a specified number of frames.

* **Frame-Based Animation:** The animation is frame-based.  For each frame, the program calculates the interpolated pose and prints it to the console. In a real application, this data would be sent to the robot's motor controllers.

* **Realistic Angles:**  The code limits the random joint angles to a reasonable range ( -PI/4 to PI/4 radians, or -45 to 45 degrees). This prevents the robot from trying to assume impossible or dangerous positions.

* **`std::chrono` for Seeding:** Uses `std::chrono` to seed the random number generator, making it far less likely to produce the same sequence of "random" poses every time the program is run.

* **Comments:**  The code is thoroughly commented, explaining each step.

* **Compile and Run:**
   ```bash
   g++ robot_dance.cpp -o robot_dance -std=c++11 # or c++14, c++17, c++20
   ./robot_dance
   ```

* **Improvements for a More Realistic System:**

    * **Inverse Kinematics:**  Instead of directly controlling joint angles, a more advanced system would use inverse kinematics.  You would specify the desired position and orientation of the robot's end-effectors (hands and feet), and the inverse kinematics solver would calculate the required joint angles.
    * **Trajectory Planning:**  Instead of linear interpolation, use trajectory planning algorithms (e.g., spline interpolation, RRT) to create smoother and more energy-efficient movements.
    * **Collision Avoidance:**  Implement collision detection and avoidance to prevent the robot from colliding with itself or its environment.
    * **Dynamics Simulation:**  Incorporate a dynamics simulation to account for the robot's inertia, gravity, and other forces. This will allow you to generate more realistic and physically plausible movements.
    * **Feedback Control:**  Use feedback control to compensate for errors in the robot's movements. This will ensure that the robot follows the desired trajectory accurately.
    * **Reinforcement Learning:** Train an AI agent using reinforcement learning to generate dance routines automatically.  The agent would learn to maximize a reward function that incorporates factors such as aesthetics, energy efficiency, and dynamic stability.

This improved example provides a solid foundation for building a more sophisticated robot dance animation system.  Remember to adjust the joint angle ranges and animation parameters to suit the specific characteristics of your robot.  Good luck!