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bstadt/pmCalibrate

pmCalibrate is an open source API for calculating the offset of a wrist mounted camera from the end effector of a robot. The method used is the Park and Martin method found here http://ieeexplore.ieee.org/document/326576/

pmCalibrate

pmCalibrate is an open source API for calculating the offset of a wrist mounted camera from the end effector of a robot arm.
It utilizes the Park and Martin method for solving Ax=xB on the Euclidean group first published here.

Request Format

Request Type: POST

Endpoint: http://park-martin-calibrate.herokuapp.com/calc

Data:

{
  "Qee": [
           [qx, qy, qz, qw, x, y, z],
           [qx, qy, qz, qw, x, y, z],
           ...
           [qx, qy, qz, qw, x, y, z]
         ],
  "Qmarker": [
              [qx, qy, qz, qw, x, y, z],
              [qx, qy, qz, qw, x, y, z],
              ...
              [qx, qy, qz, qw, x, y, z]
             ]
}

Where: qx, qy, qz, qw are quaternian rotation values, and x, y, z are translation values.

Returns:

{
  "Rx":[
         [R11, R12, R13],
         [R21, R22, R23],
         [R31, R32, R33]
       ],
  "t":[tx, ty, tz]
}

Example in Python

import requests
import json

Qee =((0.504,-0.082,0.371,0.141,0.737,-0.124,0.649),
      (0.511,-0.018,0.371,0.094,0.744,-0.083,0.656),
      (0.485,-0.071,0.312,0.291,0.724,-0.302,0.547))

Qmarker = ((-0.079,0.038,0.362,0.373,0.648,-0.561,-0.355),
           (-0.046,-0.016,0.360,0.335,0.669,-0.583,-0.315),
           (-0.102,0.042,0.296,0.535,0.574,-0.413,-0.462))

response = requests.post('http://park-martin-calibrate.herokuapp.com/calc',
                          data=json.dumps({'Qee':Qee, 'Qmarker':Qmarker}))
                          
responseObj = json.loads(response.text)
print responseObj['Rx']
print responseObj['t']

Contributors

BS
Created March 21, 2017
Updated March 20, 2018