Our Torobo Arm research platform is developed to accelerate our clients' research and development.

Received Jitsuyoka Tech Award from The Robotics Society of Japan in 2018 and Excellent Product Award from the Japan Society of Mechanical Engineers in 2016


Torque sensor for each joint

Because all of its joints have torque sensors, Torobo Arm detects torques more accurately than the current-based torque sensing method. Torobo Arm also enables softer external force following/force control and safer contact detection.

Source code provided

Torobo Arm comes with the source code of the master controller (servo controller; written in C) and PC (host controller; written in C#). You can customize the robot control system from low-level control (such as torque control) to high-level control (such as path control).


Because Torobo Arm is ROS-compatible, it is easily connected to other ROS-based systems. For example, you can quickly construct a manipulation system by combining ROS/MoveIt! with a camera, and develop a mobile manipulator in conjunction with a mobile robot.

Industrial-level performance

Although Torobo Arm is a research platform, its high-stiffness and high-quality parts guarantee industrial-level performance. The repeatability is 0.05 mm.

Small and light robot controller

The robot controller (master controller) is W170 mm × H50 mm × D120 mm in size, and weighs about 1 kg. Accordingly, the controller can be easily mounted on a mobile robot.

Driven by DC 24 V

As the power supply is 24 V DC, no special power source is required. The arm can also be driven by a battery, which is useful for autonomous mobile manipulators.


Motion learning of robot by machine learning techniques

For machine learning techniques like reinforcement learning, exploration behavior is necessary. Torobo Arm can perform it without breaking the robot and/or surrounding objects.

Feasibility study of force-controlled robot for production line

Force control is necessary for tasks such as part insertion without breaking the part, the robot, or surrounding objects. You can install the force-controlled robot in a production line, and evaluate its performance in a feasibility study.

Application for mobile manipulators

Since Torobo Arm is driven by 24V DC and its controller is small, it is best used for mobile manipulators. If you implement impedance characteristics on its joints based on the joint torque control, it can achieve stable reaching by absorbing the position error occurred in the image processing.

Research on human coexistence and collaborative robots

Human coexistence and collaborative robots require high contact safety. Using the force control and torque detection functions, you can research and develop a robot that does not harm humans.

Research on hardware parameter estimation

Because you can obtain the joint angle, angle velocity, current, and torque, you can estimate the hardware parameters such as the center of mass, moment of inertia, and friction coefficient in a research study. Torobo Arm is also useful for designing disturbance observers.

Education of control theory and motion planning

Students can alter the robot's movement by changing the PID parameters of the joints. In this way, they can understand the characteristics of the PID parameters. They can also learn how to implement kinematics and dynamics in an actual robot.

Torobo Arm Series

Torobo Arm

Torobo Arm Mini

Torobo Arm (non-brake type) * no longer in production



Torobo Arm Torobo Arm Mini
Degrees of freedom 7 7
Reach 600 mm 600 mm
Weight 19 kg 13 kg
Payload 6 kg 3 kg
Rotation range Joint 1 +/-170 degree +/-165 degree
Joint 2 +115~-45 degree +/-110 degree
Joint 3 +/-165 degree +/-165 degree
Joint 4 +125~-70 degree +/-120 degree
Joint 5 +/-165 degree +/-170 degree
Joint 6 +/-120 degree +/-105 degree
Joint 7 +/-170 degree +/-170 degree
Maximum angular velocity 120 degree/s (Joint 1~4)
180 degree/s (Joint 5~7)
120 degree/s (Joint 1~2)
160 degree/s (Joint 3~4)
200 degree/s (Joint 5~7)
Repeatability +/-0.05 mm
Sensors 19/18-bit absolute encoder (output/input)
Torque sensor (all joints)
Current sensor (all joints)
Motor Blushless DC Motor
Gear Harmonic Drive™
Poser supply DC 24 V




  • System Overview

    Torobo Arm is a very simple system consisting of a manipulator, master controller (robot controller), and your own PC. The manipulator can be placed on a base (sold as an optional extra). The power supply is a switching power supply, a stabilized power supply, or a battery that outputs 24 V DC. For a battery and a switching power supply that doesn't allow the load-side voltage fluctuation, a shunt regulator also needs to be used. Because the package includes the sample source code, ROS packages, and a user manual, you can move the arm on the day of delivery.

  • Control Architecture

    The master controller in the above figure runs a servo loop and sends the target current values to the robot arm. Its communication frequency is about 1 kHz. Each joint of the robot arm has a slave controller, which exchanges the joint data with the master controller and controls the motor current. The PC (host controller) sends the target values (joint angle, angular velocity, torque, and current), the joint space path (time, angle, and angular velocity of each joint), and the control parameters to the master controller. The host controller operates in Windows or Ubuntu, and its control frequency depends on the task processing of the operating system.

  • Master Controller (Robot Controller)

    The master controller has a built-in CPU board mounted with an RX-series processor manufactured by Renesas Electronics. You can download the compiled code via USB or perform on-chip debugging via JTAG. As the master controller also has two Ethernet ports, you can implement Ethernet/EtherCAT communication by yourself.

    The source code of the master controller implements not only the servo control of the angles, angular velocities, torques, and currents of all joints, but also the functions of the gravity and inertia compensation, external force following with torque sensors, and trajectory control. You can modify and build the sample code using e² studio (Renesas' Eclipse-based IDE).

  • Host Controller

    The host controller is a Windows application written in C#, and the source code is provided. It executes 1) the joint-level control based on the target angle, angular velocity, torque, and current, 2) the path control based on the PVT data (joint angle and angular velocity at each time), and 3) logging of the joint data.

    Panels 1–7 of the figures are explained below.

    1. Set the COM port and baud rate for communication.
    2. Show the angle, angular velocity, torque, current, and driver temperature obtained from the arm's joints. Also show the time stamp of the master controller, the set values of the control parameters, and the number of processing points for path control.
    3. Set and show the target points, write/read them to/from a CSV file. Point-to-point movement is possible based on these target points.
    4. Input the commands to set the control mode of the arm and send the target values to the arm. This area also shows the history of the input commands
    5. Save the logs of all joints (the time-stamp interval in the log file is about 1 ms).
    6. Execute the commands sequentially and save them in a CSV file.
    7. Send the joint space path (usually generated by a kinematic simulator) to the master controller, and run the trajectory control.
  • ROS

    ROS (Robot Operating System) is a middleware for robots. By using the Torobo Arm ROS package, you can achieve the followings:

    - Since it supports "control_msgs" (standard message type of ROS), you can easily operate the arm with your C++ / Python program.

    - Since it supports a ROS visualization tool "Rviz", you can check the current position and target position of the arm by 3-dimensional view.

    - Since it supports a path-planning software "MoveIt!", which is widely used in the ROS community, you can easily use advanced functions such as kinematics calculation, collision detection, and path planning.

    - Since it supports the physics simulator "Gazebo", you can test your own program for controlling the Torobo Arm on the PC.

    - You can directly control the joints of the arm by using a GUI tool "torobo_joint_controller".

    - You can check the joint state and send it a control command by using a GUI tool "torobo_state_viewer" (only for the actual arm).

    It is recommended to use this package in the following PC environment:

    CPU Intel i5, equivalent or greater
    RAM 4GB or larger
    Disk Space 15GB or larger
    OS Ubuntu 16.04 LTS
    ROS Version ROS Kinetic Kame

Basic Package



Robot Base

The size is W:800mm, H:880mm, and D:800mm. Because we provide the drawing of the bottom of robot, you can prepare a base by yourself.



This is a slide-open type gripper. Because it uses the internal bus, you don't need to worry about cabling. You can change its fingers according to your application.