how to interpret the SpaceMouse position values and translate them into appropriate displacement values for the end effector in my simulation.

I'm currently working on a project where I'm using a SpaceMouse to control the position of an end effector in a simulation environment. I've successfully connected MATLAB to my simulation software, CoppeliaSim, and I'm able to read the position values from the SpaceMouse using MATLAB. However, I'm now at a point where I need to calculate the desired position of the end effector based on the input from the SpaceMouse.

Specifically, I'm looking for guidance on how to interpret the SpaceMouse position values and translate them into appropriate displacement values for the end effector in my simulation. Since the initial position values for the SpaceMouse are all 0, I need assistance in understanding how changes in these values correspond to movements or rotations in my simulation environment.

Any insights or suggestions on how to approach this problem would be greatly appreciated. Thank you!

Answer 1

[Nivedita]

Hi Mushtariy,

I do not have much knowledge on your query but I can provide you some steps to get you started, hope they help.

1. The SpaceMouse typically provides six degrees of freedom (DOF) input: three for translation (X, Y, Z) and three for rotation (pitch, yaw, roll). These inputs are usually given as relative changes from a neutral position (0, 0, 0 for translation and 0, 0, 0 for rotation).
2. The raw input values from the SpaceMouse are often not directly usable as they might be too large or too small. You will need to scale these values appropriately.
3. You will need to maintain the current position and orientation of the end effector and update it based on the scaled input from the SpaceMouse.

Here's a sample MATLAB code that you can utilize:

% Initialize current position and orientation of the end effector
currentPosition = [0, 0, 0]; % [x, y, z]
currentOrientation = [0, 0, 0]; % [pitch, yaw, roll]

% Scaling factors for translation and rotation
translationScale = 0.001; % Adjust this as needed
rotationScale = 0.001; % Adjust this as needed

% Function to update end effector position based on SpaceMouse input
function updateEndEffector(spaceMouseInput)
    global currentPosition;
    global currentOrientation;

    % Extract translation and rotation inputs
    translationInput = spaceMouseInput(1:3); % [x, y, z]
    rotationInput = spaceMouseInput(4:6); % [pitch, yaw, roll]

    % Scale the inputs
    translationDelta = translationInput * translationScale;
    rotationDelta = rotationInput * rotationScale;

    % Update the current position and orientation
    currentPosition = currentPosition + translationDelta;
    currentOrientation = currentOrientation + rotationDelta;

    % Update the simulation (CoppeliaSim) with the new position and orientation
    % Assuming you have a function to send these values to CoppeliaSim
    sendToCoppeliaSim(currentPosition, currentOrientation);
end

% Dummy function to simulate sending data to CoppeliaSim
function sendToCoppeliaSim(position, orientation)
    % This function should contain the code to update the simulation
    % For example, using remote API commands
    disp('Position:');
    disp(position);
    disp('Orientation:');
    disp(orientation);
end

% Example usage
% Assuming spaceMouseInput is a 1x6 vector obtained from the SpaceMouse
spaceMouseInput = [0.5, -0.2, 0.1, 0.01, -0.02, 0.03];
updateEndEffector(spaceMouseInput);

Important things to note:

• You may need to experiment with the scaling factors to find values that provide smooth and intuitive control.
• Ensure that you have the necessary functions to communicate with CoppeliaSim.