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schunk_modular_robotics: CANOpen_driver | schunk_description | schunk_libm5api | schunk_powercube_chain | schunk_sdh | schunk_simulated_tactile_sensors

Package Summary

This packages provides a configurable driver of a chain of Schunk powercubes. The powercube chain is configured through parameters. Most users will not directly interact with this package but with the corresponding launch files in other packages, e.g. schunk_bringup, cob_bringup, ...

• Author: Florian Weisshardt
• License: LGPL
• Repository: care-o-bot
• Source: git git://github.com/ipa320/schunk_modular_robotics.git

Hardware Requirements

To use this package you need one or more powercubes www.schunk-modular-robotics.com. Alternatively you can use a simulated version without any hardware, see schunk_bringup_sim.

ROS API

The schunk_powercube_chain package provides a configurable node for operating a chain of powercube modules.

schunk_powercube_chain

The schunk_powercube_chain node takes in brics_actuator/JointVelocities messages and send this directly to the hardware. The chain can be initialized, stopped or recovered via services.

Subscribed Topics

command_vel (brics_actuator/JointVelocities)

• Receives velocity commands.

Services

init (cob_srvs/Trigger)

• Initializes the node and connects to the hardware.

stop (cob_srvs/Trigger)

• Stops immediately all hardware movements.

recover (cob_srvs/Trigger)

• Recovers the hardware after an emergency stop.

set_operation_mode (cob_srvs/Trigger)

• Sets the operation mode for the node.

Parameters

~can_module (string, default: Required)

• Can module specifier, e.g. PCAN, ESD

~can_device (int, default: Required)

• Device address of can module, e.g. /dev/can0, /dev/pcan2,...

~can_baudrate (int, default: Required)

• Baudrate of can module, e.g. 1000, 500,...

~module_ids (list of ints, default: Required)

• Modul IDs of the powercubes, e.g. [10,11,12,13,...]

~joint_names (list of strings, default: Required)

• List of joint names corresponding to urdf description, e.g. [arm_1_joint, arm_2_joint, arm_3_joint,...]

~max_accelerations (list of doubles, default: Required)

• List of maximal accelerations for the modules in rad/sec^2, e.g. [0.8,0.8,0.8,...]

~OperationMode (string, default: Required)

• Operation mode of the modules, e.g. position, velocity

/robot_description (urdf model, default: Required)

• Urdf model of the robot, including the joints and links describing the used powercubes

Usage/Examples

This package is not intended to be used directly, but with the corresponding launch and yaml files from e.g. schunk_bringup in the schunk_robots stack. For starting only the lwa use

roslaunch schunk_bringup lwa_solo.launch

For including the lwa in your overall launch file use

<include file="$(find schunk_bringup)/components/lwa.launch" />

All hardware configuration is done in the schunk_hardware_config package. A sample parameter file in "schunk_hardware_config/lwa/config/lwa.yaml" could look like this

can_module: PCAN
can_device: /dev/pcan1
can_baudrate: 1000
modul_ids: [1,2,3,4,5,6,7]
joint_names: [arm_1_joint, arm_2_joint, arm_3_joint, arm_4_joint, arm_5_joint, arm_6_joint, arm_7_joint]
max_accelerations: [0.8,0.8,0.8,0.8,0.8,0.8,0.8]
frequency: 68
OperationMode: position
ptp_vel: 0.4 # rad/sec
ptp_acc: 0.1 # rad/sec^2
max_error: 0.2 # rad