What is a Minitaur quadruped?

Minitaur is a high-performance small quadruped robot developed by Ghost Robotics in the early stage. Although it only has 8 degrees of freedom, it has unusual movement ability and the ability to jump over obstacles and flip as well as that of MIT cheetah. Minitaur uses 8 brushless motors as its power source, and the whole machine weighs 4kg. It has a maximum speed of 2m/s and a endurance of about 20 minutes. Although legs are designed in parallel, the force control algorithm based on Kodlab can achieve stable Trot, Bound and Pronk gaits, making it a low-cost, high-performance platform for quadruped robot development.

Website: GhostRobotic www.kodlab

What is Webots emulation? Webots is a professional mobile robot simulation software package. It provides a rapid prototyping environment that allows users to create 3D virtual worlds with physical properties such as mass, joints, friction coefficients, etc. Users can add simple passive objects or active objects called mobile robots. These robots can have different mobility schemes (wheeled robots, legged robots or flying robots). Furthermore, they may be equipped with many sensor and actuator devices, such as distance sensors, drive wheels, cameras, motors, touch sensors, transmitters, receivers, etc. Finally, users can program each robot individually to exhibit the desired behavior. Webots contains numerous robot models and sample controller programs to help users get started. Webots also include a number of interfaces with real mobile robots, so once your simulated robot behaves as expected, you can transfer its control programs to real robots such as E-Puck, Darwin-op, and Nao. New interfaces can be added through the relevant system.

Typical application scenarios: testing robot algorithms (navigation, planning, control, vision, etc.)

Webots features: rich physics engine rich robot model and environment library a variety of sensors to choose from convenient robot modeling interface

Related website: Webots website

What is the use of Webots based quadruped robot simulation? Webots simulation is the choice of many simulation software for robots, which has rich sensors and drive units. Meanwhile, it can be jointly developed with ROS and Matlab and other environments. It supports rich programming languages such as Python and C++ and has convenient robot modeling interface. Through the installation of cameras or radar sensors, the development of SLAM algorithm and the research of robot navigation planning algorithm can be realized based on Webots. The simulation of quadruped robot based on Webots can help us test and verify the control logic, framework and state estimation algorithm before the actual deployment of the algorithm.

For quadruped robot based on Webots can achieve the following simulation purposes: 1. Control algorithm verification. In fact, regardless of the study of any robot control algorithm, especially for the bionic robot such a multi-degree of freedom system, in the actual system to deploy the control algorithm before simulation is very necessary. In addition to verifying the kinematics and Jacobian matrix of the robot, simulation can not prove the correctness of the theory without verification of more advanced control algorithms such as MPC or WBC. At the same time, simulation can also provide advance verification for complex control strategies, help to quickly find bugs in logic design, and provide a general range for parameter setting.

2. SLAM algorithm verification. With the help of the powerful function of Webots, you can add cameras, lidar and other sensors to the simulation environment, build a simulation environment close to the real world through the simulator, test the relevant detection, recognition and other visual algorithms function. In this way, combined with the real robot model, the SLAM algorithm can be verified quickly, and the trajectory planning and control algorithm of the robot can be designed at the same time. Finally, the navigation logic and trajectory planning structure can be rapidly deployed in the actual system only to ensure the reliability of the implementation and positioning of control commands.

3. Development and design of quadruped robot. With the help of the Webots strong ability, you can import your own robots in the Webots model, and the quadruped robot leg connecting rod and validated the reliability of the transmission system design, efficiency, of the various components by defining the material parameters accurately, can make the final simulation model that is consistent with the physical prototype, appearance and related kinetic parameters, So that the relevant control parameters in the simulation have more practical reference value.

What is the focus of this project? This project builds a basic quadruped robot control framework for users. Minitaur 8-DOF quadruped robot model is used to realize standing control, Trot movement control and Pronk jump control. Based on virtual model control theory, QP nonlinear optimization and inverted pendulum control theory, Learn the basic control method of quadruped robot and swing drop foot point planning is rich, on this basis, we will complete up and down slopes, up and down steps, through rugged terrain simulation test.

The program provides a framework for basic standing and Trot motion control for a quadruped robot. Tutorial: Webots related API use, quadruped robot basic control algorithm tutorial.

The first phase of the task we will complete is to conduct a standing gait test in the Webots environment and adjust and control the robot’s attitude Angle and centroid position through the given expected state.

The second stage is to carry out the Tort trot gait test in the Webots environment, and realize the closed-loop control of the robot speed by the expected speed given.

Phase III: Pronk jumping gait movement test was conducted in the Webots environment, and robot jumping was realized based on the energy control principle.

The fourth phase: improve the relevant control interface, introduce terrain Angle estimation and other mechanisms to realize the control of up and down slopes and through rugged terrain.

Interested friends welcome to join the project group communication group, comment section to view oh ~

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