ptc 0.0.1.dev20200721152952

Pulse Tool Calibration library

Pulse Tool Calibration Library

Utility library (ptc) and command line interface (ptc-cli) to calculate tool offset for Pulse Robotic Arm.

Installation

Standalone library:

pip3 install -U ptc

Command line interface and library:

pip3 install -U ptc-cli

Usage

Basic usage, assuming that you have followed installation step and installed the ptc-cli package.

In order to determine the tool offset, you MUST provide at least 4 different positions, that represent the same point in space with tool installed. The more points you give the better calibration precision could be achived.

The positions could be obtained using the get_position() method from pulse-api library and should be provided in a text file in the following order:

x, y, z, roll, pitch, yaw

Each position MUST be on a separate line and the values MUST be separated with comas.

Calculation is performed using following command in terminal:

ptc-cli --file /absolute/path/to/your/positions/file

The output will be the calculated tool offset:

[x_offset, y_offset, z_offset]

This output could be used in the change_tool_info method of the pulse-api library.

Example

Sample file with robot positions located at /home/user/sample.csv:

0.4000000016853294, -0.39999999880983755, 0.3000000025723091, -3.1415926381331523, 2.188741009988131e-08, 2.6794896299132232e-08
0.4000000029422969, -0.2999999962803114, 0.19999999804274032, 1.5707963642922351, 3.757424773546488e-15, 7.285142337505987e-08
0.3292893264445241, -0.4707106768261343, 0.2000000019309496, -1.5707963309948643, 0.7853981633974412, -5.0320115533448106e-08
0.47071067682613615, -0.32928932644452064, 0.19999999806904972, 1.570796322594932, -0.7853981633974498, 5.363765550429646e-08

Terminal command:

ptc-cli --file /home/user/sample.csv

Output:

Calculated TCP offset: [0.00027102 0.00027103 0.10055737]

To get more detailed output:

ptc-cli --file /home/user/sample.csv --verbose

Output:

Calculated TCP offset: [0.00027102 0.00027103 0.10055737]
More detailed calibration info:
 active_mask: array([0., 0., 0.])
        cost: 5.770939282001564e-13
         fun: array([5.31035219e-07, 7.68248630e-07, 5.31035183e-07])
        grad: array([1.27999602e-09, 1.28000956e-09, 2.89674021e-09])
         jac: array([[1.62617755e-03, 3.03639571e-12, 1.11474501e-03],
       [5.42062087e-04, 5.42079840e-04, 2.22948991e-03],
       [1.68880868e-11, 1.62617750e-03, 1.11474494e-03]])
     message: '`gtol` termination condition is satisfied.'
        nfev: 11
        njev: 10
  optimality: 2.8967402130836482e-09
      status: 1
     success: True
           x: array([0.00027102, 0.00027103, 0.10055737])