matlab kinematics module  (MathWorks Inc)

Journal: Bioinspiration & biomimetics

Article Title: A robotic leg inspired from an insect leg.

doi: 10.1088/1748-3190/ac78b5

Figure Lengend Snippet: Figure 3. Setup for the experiment to track the trajectories of the beetle legs and body. (A) 3D motion-capturing system consists of (i) six T40 VICON cameras (Vicon Motion Systems, Oxford, UK), each with an equal resolution of 4 megapixels (2336 × 1728) for tracking the position (100 fps), (ii) the VICON server for recording, storing and showing the 3D position collected by the cameras and (iii) MATLAB software (MathWorks, Natick, MA, USA) for analyzing the angular displacement and the distance among positions. (B) Three reflective markers were stuck on each front leg to represent the tarsus and tibia segments. The L-shape structure with three reflective markers was attached to the beetle’s body, allowing the reference plane to be made. (C) Diagram showing how angular displacement was calculated. Angle between claw and tibia is used to describe the bending ability of the tarsus. (D) These markers were displayed by the points on the Nexus software. To present the tibia and tarsus segments of each front leg and the beetle’s body, we linked the three points on the left and right front leg and three points on the body. We investigated the movement of the front legs of the beetle when walking on the plate and mesh substrates by measuring the displacement D of the claws. (E) Setup used to measure the horizontal force (hooking force) and vertical force of the artificial tarsus when it switched to rigid condition includes (i) the digital force gauge (SAUTER FH100) to measure force values and transfer data to the PC, (ii) the linear guide slide to move the tarsus during the hooking force measurement and (iii) actuator AX12A for pulling the string to bend the tarsus.

Article Snippet: The Denavit–Hartenberg (DH) parameters of the robotic leg were then configured in the MATLAB kinematics module (Robotics System Toolbox) to translate the scaled trajectory into the motors’ joint angles (figure 10(B)).

Techniques: Software

Journal: Bioinspiration & biomimetics

Article Title: A robotic leg inspired from an insect leg.

doi: 10.1088/1748-3190/ac78b5

Figure Lengend Snippet: Figure 10. Demonstration with the 3D printed tarsus. Visual deformation of the artificial tarsus. (A) Inverse kinematics method was applied to control the movement of the robot leg so that the robot tibia can generate a similar trajectory to the beetle’s tibia. (B) DH parameters for the configuration of the robotic leg: segments 1, 2, 3, and 4 represent coxa, trochanter, femur and tibia respectively. (C) Simulating the movement of the robot leg on the mesh substrate. When the motor ‘contracts’, which is denoted as state 1, the tarsus is bent so that the claws attach to the mesh. Moreover, the claws still hook onto the mesh when the leg switches to the swing phase, while the height of the mesh follows that of the claws closely, indicating attachment. When the leg returns and the motor ‘relaxes’, which is denoted as state 2, the tarsus switches to flexible condition. Then, the claws can come out of the mesh, and the height of the mesh does not rise past its resting height, indicating release.

Article Snippet: The Denavit–Hartenberg (DH) parameters of the robotic leg were then configured in the MATLAB kinematics module (Robotics System Toolbox) to translate the scaled trajectory into the motors’ joint angles (figure 10(B)).

Techniques: Control