buzz_kh4

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Buzz on the Khepera IV

The Khepera IV is a commercial robot produced by K-Team.

A Buzz port for the Khepera IV is available at https://github.com/MISTLab/BuzzKH4. An ARGoS plugin to simulate the robot is available at https://github.com/ilpincy/argos3-kheperaiv.

  • Wheels
  • set_wheels(lws,rws) sets the speed of the wheels to lws (left wheel speed) and rws (right wheel speed). The speed is expressed in cm/sec. The maximum speed of the real Khepera is about 20 cm/sec.
  • gotop(ls,as) sets the speed of the center of mass of the robot. The speed is expressed as a vector in polar coordinates, where ls is the linear speed (i.e., the forward speed, in cm/sec) and as is the angular speed (i.e., in rad/sec). The vector is internally transformed into wheel actuation.
  • gotoc(sx,sy) sets the speed of the center of mass of the robot. The speed is expressed as a vector in cartesian coordinate, where sx is the linear speed along the local x axis of the robot (i.e., the forward speed, in cm/sec) and sy is the linear speed along the local y axis of the robot (a vector pointing left, according to the right-hand rule). The vector is internally transformed into wheel actuation.
  • LEDs
  • set_leds(r,g,b) sets the color of the three LEDs on top of the Khepera IV. The color is expressed with 0-255 values for each of the channels (red, green, blue).
  • Proximity sensors
    • The Khepera IV proximity sensor is a set of 8 infrared emitter/receiver pairs distributed regularly in a ring around the robot. The sensors are numbered 0 to 7. Sensor 0 looks straight ahead, and the numbers increase counterclockwise when looking at the robot from above.
    • proximity is the Buzz table that contains the proximity readings. Each element of this table (e.g., proximity[0], proximity[1], …) is in turn a table that contains two elements:
      • angle, which corresponds to the angle (expressed in radians) at which the sensor is located on the body of the robot
      • value, which is the actual reading. Each individual sensor is saturated (value 1.0) by objects closer than 4 cm; the maximum range of the sensor is 12 cm. Between 4 and 12 cm, the readings follow an exponential law with the distance: 4.14*exp(-33.0*distance)-.085.
  • buzz_kh4.1521507086.txt.gz
  • Last modified: 2018/03/20 00:51
  • by root