remove getHandle in UnitreeHW::read

[zitongbai]

I would like to express my gratitude for the wonderful framework you have shared with the community. It has been instrumental in advancing my project.

I am currently working on implementing two distinct, self-defined ROS controllers to control separate groups of joints. But this would cause resource conflict in ros control manager, the error information would be like:

[ WARN] [1723711230.086462426]: Resource conflict on [left_ankle_joint].  Controllers = [controllers/init_joint_pos_controller, controllers/upper_joint_controller, ]
[ WARN] [1723711230.086604701]: Resource conflict on [left_elbow_joint].  Controllers = [controllers/init_joint_pos_controller, controllers/upper_joint_controller, ]
[ WARN] [1723711230.086661049]: Resource conflict on [left_hip_pitch_joint].  Controllers = [controllers/init_joint_pos_controller, controllers/upper_joint_controller, ]
[ WARN] [1723711230.086710601]: Resource conflict on [left_hip_roll_joint].  Controllers = [controllers/init_joint_pos_controller, controllers/upper_joint_controller, ]
[ WARN] [1723711230.086752277]: Resource conflict on [left_hip_yaw_joint].  Controllers = [controllers/init_joint_pos_controller, controllers/upper_joint_controller, ]
[ WARN] [1723711230.086901553]: Resource conflict on [left_knee_joint].  Controllers = [controllers/init_joint_pos_controller, controllers/upper_joint_controller, ]
[ WARN] [1723711230.086953870]: Resource conflict on [left_shoulder_pitch_joint].  Controllers = [controllers/init_joint_pos_controller, controllers/upper_joint_controller, ]
[ WARN] [1723711230.086997766]: Resource conflict on [left_shoulder_roll_joint].  Controllers = [controllers/init_joint_pos_controller, controllers/upper_joint_controller, ]
[ WARN] [1723711230.087036690]: Resource conflict on [left_shoulder_yaw_joint].  Controllers = [controllers/init_joint_pos_controller, controllers/upper_joint_controller, ]
[ WARN] [1723711230.087073432]: Resource conflict on [not_use_joint].  Controllers = [controllers/init_joint_pos_controller, controllers/upper_joint_controller, ]
[ WARN] [1723711230.087122926]: Resource conflict on [right_ankle_joint].  Controllers = [controllers/init_joint_pos_controller, controllers/upper_joint_controller, ]
[ WARN] [1723711230.087178554]: Resource conflict on [right_elbow_joint].  Controllers = [controllers/init_joint_pos_controller, controllers/upper_joint_controller, ]
[ WARN] [1723711230.087232702]: Resource conflict on [right_hip_pitch_joint].  Controllers = [controllers/init_joint_pos_controller, controllers/upper_joint_controller, ]
[ WARN] [1723711230.087275688]: Resource conflict on [right_hip_roll_joint].  Controllers = [controllers/init_joint_pos_controller, controllers/upper_joint_controller, ]
[ WARN] [1723711230.087315841]: Resource conflict on [right_hip_yaw_joint].  Controllers = [controllers/init_joint_pos_controller, controllers/upper_joint_controller, ]
[ WARN] [1723711230.087356746]: Resource conflict on [right_knee_joint].  Controllers = [controllers/init_joint_pos_controller, controllers/upper_joint_controller, ]
[ WARN] [1723711230.087425316]: Resource conflict on [right_shoulder_pitch_joint].  Controllers = [controllers/init_joint_pos_controller, controllers/upper_joint_controller, ]
[ WARN] [1723711230.087476459]: Resource conflict on [right_shoulder_roll_joint].  Controllers = [controllers/init_joint_pos_controller, controllers/upper_joint_controller, ]
[ WARN] [1723711230.087515868]: Resource conflict on [right_shoulder_yaw_joint].  Controllers = [controllers/init_joint_pos_controller, controllers/upper_joint_controller, ]
[ WARN] [1723711230.087555049]: Resource conflict on [torso_joint].  Controllers = [controllers/init_joint_pos_controller, controllers/upper_joint_controller, ]
[ERROR] [1723711230.087743598]: Could not switch controllers, due to resource conflict

More details can be found in my forked version: zitongbai/bipedal_control#3

Upon further examination, I found that the calling of the getHandle("handle_name") function of HybridJointInterface would claim the "handle_name" resource, which can be referred here:

https://github.com/ros-controls/ros_control/blob/6b9fd8b3605e047ae1b925857c92998074c803c4/hardware_interface/include/hardware_interface/internal/hardware_resource_manager.h#L65-L70

And I found that the getHandle function is called in UnitreeHW::read, which causes all the joints resources are claimed each time UnitreeHW::read is invoked, no matter whether they are used in the controller:

legged_control/legged_examples/legged_unitree/legged_unitree_hw/src/UnitreeHW.cpp

Lines 85 to 92 in 715cc53

	// Set feedforward and velocity cmd to zero to avoid for safety when not controller setCommand
	std::vector<std::string> names = hybridJointInterface_.getNames();
	for (const auto& name : names) {
	HybridJointHandle handle = hybridJointInterface_.getHandle(name);
	handle.setFeedforward(0.);
	handle.setVelocityDesired(0.);
	handle.setKd(3.);
	}

Of course, it poses no issues in the context of a single controller implementation. But it will cause some trouble when attempting to operate multiple controllers concurrently, which may be essential for further development.

Furthermore, I have yet to conduct real-world experiments to validate this behavior. It would be highly beneficial to have this aspect confirmed through practical testing :)

[qiayuanl]

Should not be i<12.

[qiayuanl]

Better to have some damping
jointData_[i].kd_ = 3.0;

[qiayuanl]

Not need for these two lines.

[qiayuanl]

Hi, thanks for your contribution, I think you are right. I left some details comments for the code. In addition, can you use clang-format for your code with this configuration so I can merge it into the master repo?