
具身智能(Embodied Intelligence)强调智能体通过与物理环境的交互来学习和发展认知能力。其核心技术包括感知、决策、控制和多模态学习等模块。
感知模块依赖计算机视觉、深度学习和传感器融合技术,用于理解环境状态。决策模块采用强化学习、规划算法和认知建模,生成行动策略。控制模块通过机器人学和运动规划技术,将决策转化为具体动作。
视觉-触觉多模态感知系统常用于物体识别和操作。以下案例使用PyTorch实现视觉与触觉数据融合:
import torch
import torch.nn as nn
class MultimodalEncoder(nn.Module):
def __init__(self):
super().__init__()
self.visual_net = nn.Sequential(
nn.Conv2d(3, 32, kernel_size=3),
nn.ReLU(),
nn.MaxPool2d(2),
nn.Conv2d(32, 64, kernel_size=3),
nn.ReLU()
)
self.tactile_net = nn.Sequential(
nn.Linear(128, 64),
nn.ReLU(),
nn.Linear(64, 32)
)
self.fusion_layer = nn.Linear(96, 64)
def forward(self, visual_input, tactile_input):
visual_feat = self.visual_net(visual_input).mean(dim=[2,3])
tactile_feat = self.tactile_net(tactile_input)
combined = torch.cat([visual_feat, tactile_feat], dim=1)
return self.fusion_layer(combined)该架构将224x224 RGB图像和128维触觉数据编码为64维联合表征,可用于抓取任务中的物体属性识别。
基于深度强化学习的运动策略训练采用PPO算法:
import gym
import torch
from stable_baselines3 import PPO
from stable_baselines3.common.env_util import make_vec_env
env = make_vec_env("PandaReach-v2", n_envs=4)
policy_kwargs = dict(activation_fn=torch.nn.ReLU,
net_arch=[dict(pi=[256, 256], vf=[256, 256])])
model = PPO("MlpPolicy", env, policy_kwargs=policy_kwargs,
verbose=1, batch_size=256, n_steps=1024)
model.learn(total_timesteps=1_000_000)该代码在模拟机械臂到达任务中训练策略网络,使用4个并行环境加速训练。网络结构包含两个256维隐藏层,采用ReLU激活函数。
运动规划结合快速随机树(RRT)算法与PD控制器:
import numpy as np
from scipy.spatial import KDTree
class RRTPlanner:
def __init__(self, bounds, step_size=0.1):
self.bounds = np.array(bounds)
self.step_size = step_size
self.tree = None
def plan(self, q_start, q_goal, max_iter=1000):
nodes = [q_start]
self.tree = KDTree([q_start])
for _ in range(max_iter):
q_rand = self._random_config()
_, q_near = self.tree.query(q_rand)
q_new = self._steer(q_near, q_rand)
if self._collision_free(q_near, q_new):
nodes.append(q_new)
self.tree = KDTree(nodes)
if np.linalg.norm(q_new - q_goal) < self.step_size:
return self._extract_path(nodes)
return None
def _steer(self, q_a, q_b):
direction = (q_b - q_a) / np.linalg.norm(q_b - q_a)
return q_a + direction * self.step_size该实现包含7自由度机械臂的路径规划,step_size参数控制规划精度,collision_free方法需根据具体场景实现碰撞检测。
使用MuJoCo物理引擎进行仿真验证:
import mujoco
import mujoco_viewer
model = mujoco.MjModel.from_xml_path("scenario.xml")
data = mujoco.MjData(model)
viewer = mujoco_viewer.MujocoViewer(model, data)
while True:
mujoco.mj_step(model, data)
viewer.render()
if data.time > 10.0:
break实物部署时需考虑状态估计和实时控制:
import rospy
from franka_interface import ArmInterface
robot = ArmInterface()
rate = rospy.Rate(100) # 100Hz control loop
while not rospy.is_shutdown():
current_pose = robot.endpoint_pose()
target_torques = controller.compute(current_pose)
robot.send_joint_torques(target_torques)
rate.sleep()该ROS节点实现100Hz控制频率,通过Franka Emika机器人接口发送力矩指令。
跨模态表示学习采用对比损失:
import torch
from torch import nn
class ContrastiveLearner(nn.Module):
def __init__(self, temp=0.1):
super().__init__()
self.temp = temp
self.cross_entropy = nn.CrossEntropyLoss()
def forward(self, vis_emb, tac_emb):
logits = vis_emb @ tac_emb.T / self.temp
labels = torch.arange(len(vis_emb)).to(vis_emb.device)
loss = (self.cross_entropy(logits, labels) +
self.cross_entropy(logits.T, labels)) / 2
return loss温度参数temp控制特征分布的紧凑程度,该损失函数促使匹配的视觉-触觉特征对相互靠近。