From 73ef89838763496b94da30ede38fc92218bea18e Mon Sep 17 00:00:00 2001
From: Daijiro Fukuda <fukuda@clear-code.com>
Date: Thu, 15 Jan 2026 18:07:21 +0900
Subject: [PATCH] Make gain configurable (#79)

Make gain configurable in HardwareInfo of the description file.

Need https://github.com/enactic/openarm_description/pull/38.
---
 .../openarm_hardware/v10_simple_hardware.hpp  | 11 ++++-----
 openarm_hardware/src/v10_simple_hardware.cpp  | 23 ++++++++++++++-----
 2 files changed, 22 insertions(+), 12 deletions(-)

diff --git a/openarm_hardware/include/openarm_hardware/v10_simple_hardware.hpp b/openarm_hardware/include/openarm_hardware/v10_simple_hardware.hpp
index aa54b7e..d6cea4b 100644
--- a/openarm_hardware/include/openarm_hardware/v10_simple_hardware.hpp
+++ b/openarm_hardware/include/openarm_hardware/v10_simple_hardware.hpp
@@ -100,17 +100,16 @@ class OpenArm_v10HW : public hardware_interface::SystemInterface {
   const uint32_t DEFAULT_GRIPPER_SEND_CAN_ID = 0x08;
   const uint32_t DEFAULT_GRIPPER_RECV_CAN_ID = 0x18;
 
-  // Default gains
-  const std::vector<double> DEFAULT_KP = {70.0, 70.0, 70.0, 60.0,
-                                          10.0, 10.0, 10.0};
-  const std::vector<double> DEFAULT_KD = {2.75, 2.5, 2.0, 2.0, 0.7, 0.6, 0.5};
+  // Gains
+  std::vector<double> kp_ = {70.0, 70.0, 70.0, 60.0, 10.0, 10.0, 10.0};
+  std::vector<double> kd_ = {2.75, 2.5, 2.0, 2.0, 0.7, 0.6, 0.5};
 
   const double GRIPPER_JOINT_0_POSITION = 0.044;
   const double GRIPPER_JOINT_1_POSITION = 0.0;
   const double GRIPPER_MOTOR_0_RADIANS = 0.0;
   const double GRIPPER_MOTOR_1_RADIANS = -1.0472;
-  const double GRIPPER_DEFAULT_KP = 5.0;
-  const double GRIPPER_DEFAULT_KD = 0.1;
+  const double GRIPPER_KP = 5.0;
+  const double GRIPPER_KD = 0.1;
 
   // Configuration
   std::string can_interface_;
diff --git a/openarm_hardware/src/v10_simple_hardware.cpp b/openarm_hardware/src/v10_simple_hardware.cpp
index 8d65dea..69f305c 100644
--- a/openarm_hardware/src/v10_simple_hardware.cpp
+++ b/openarm_hardware/src/v10_simple_hardware.cpp
@@ -60,6 +60,18 @@ bool OpenArm_v10HW::parse_config(const hardware_interface::HardwareInfo& info) {
     can_fd_ = (value == "true");
   }
 
+  // Parse control gains
+  for (size_t i = 1; i <= ARM_DOF; ++i) {
+    it = info.hardware_parameters.find("kp" + std::to_string(i));
+    if (it != info.hardware_parameters.end()) {
+      kp_[i - 1] = std::stod(it->second);
+    }
+    it = info.hardware_parameters.find("kd" + std::to_string(i));
+    if (it != info.hardware_parameters.end()) {
+      kd_[i - 1] = std::stod(it->second);
+    }
+  }
+
   RCLCPP_INFO(rclcpp::get_logger("OpenArm_v10HW"),
               "Configuration: CAN=%s, arm_prefix=%s, hand=%s, can_fd=%s",
               can_interface_.c_str(), arm_prefix_.c_str(),
@@ -260,8 +272,8 @@ hardware_interface::return_type OpenArm_v10HW::write(
   // Control arm motors with MIT control
   std::vector<openarm::damiao_motor::MITParam> arm_params;
   for (size_t i = 0; i < ARM_DOF; ++i) {
-    arm_params.push_back({DEFAULT_KP[i], DEFAULT_KD[i], pos_commands_[i],
-                          vel_commands_[i], tau_commands_[i]});
+    arm_params.push_back(
+        {kp_[i], kd_[i], pos_commands_[i], vel_commands_[i], tau_commands_[i]});
   }
   openarm_->get_arm().mit_control_all(arm_params);
   // Control gripper if enabled
@@ -269,7 +281,7 @@ hardware_interface::return_type OpenArm_v10HW::write(
     // TODO the true mappings are unimplemented.
     double motor_command = joint_to_motor_radians(pos_commands_[ARM_DOF]);
     openarm_->get_gripper().mit_control_all(
-        {{GRIPPER_DEFAULT_KP, GRIPPER_DEFAULT_KD, motor_command, 0, 0}});
+        {{GRIPPER_KP, GRIPPER_KD, motor_command, 0, 0}});
   }
   openarm_->recv_all(1000);
   return hardware_interface::return_type::OK;
@@ -282,15 +294,14 @@ void OpenArm_v10HW::return_to_zero() {
   // Return arm to zero with MIT control
   std::vector<openarm::damiao_motor::MITParam> arm_params;
   for (size_t i = 0; i < ARM_DOF; ++i) {
-    arm_params.push_back({DEFAULT_KP[i], DEFAULT_KD[i], 0.0, 0.0, 0.0});
+    arm_params.push_back({kp_[i], kd_[i], 0.0, 0.0, 0.0});
   }
   openarm_->get_arm().mit_control_all(arm_params);
 
   // Return gripper to zero if enabled
   if (hand_) {
     openarm_->get_gripper().mit_control_all(
-        {{GRIPPER_DEFAULT_KP, GRIPPER_DEFAULT_KD, GRIPPER_JOINT_0_POSITION, 0.0,
-          0.0}});
+        {{GRIPPER_KP, GRIPPER_KD, GRIPPER_JOINT_0_POSITION, 0.0, 0.0}});
   }
   std::this_thread::sleep_for(std::chrono::microseconds(1000));
   openarm_->recv_all();