AUTOMATION OF ROBOTIC ARM

Tomáš STANOVIČ

6th International Conference of young Scientists on Solutions of Applied Problems

in Control and Communications, Data Processing and Data Analysis

19.3. 2015

Introduction, objectives

Topic flows from current requirements of robotics for automated capabilities of modern robots to aimed robot at desired location, for the detection of objects in space, grasp objects, and relocate them.

Objectives : 1. Design CAD model of robotic arm (SW Autodesk Inventor).

2. Translation CAD model into Matlab SimMechanics.

3. Edit SimMehcanics model in way, that it can receive input data from GUI.

4. Create GUI for calculate data to determinate desired location of arm.

Design CAD model

I created robotic arm as a assembly consisted of 13 parts (base,cylinders for connection, gripping parts).

Cad model of robotic arm :

Translation CAD model into SimMechanics

XML into SimMechanics : import_physmod('arm.xml.‘)

Body block is user- defined rigid body which is defined by mass properties and body coordinate systems. Mass properties includes body’s mass, which determines body response to translational forces  and its intertia tensor, which determines its response to rotational torques. Body cooridnate systems define local cooridnate systems, one of them is CG – body’s center of gravity another are CS, they are asociated with joints to the body block.

Revolute block represents one rotational degree of freedom. The follower body rotates relative to the base body about a single rotational axis going through collocated body coordinate system origins. Sensor and actuator ports can be added.

Edit SimMehcanics model

• Reduce degrees of freedom from 12 to 6 – Weld block

• Run simulation

To fix problems with colliding I had to connect these blocks to every

revolute block :

1. Joint sensor - measures angular position of a joint primitive. To

sensor I joined Scope – displays measured signal

2. Joint actuator - actuates a joint block connected between two

bodies. To this block I joined :

• Sine wave (outputs a sinusoidal waveform.

y=amplitude×sin(frequency×time)

• Derivatvie block (approximates the derivative of the input

signal u with respect to the simulation time t.)

• Mux (used for combine many inputs into single output)

Results of simulation :

x = 1.6 / 10 (simulation time).

Create GUI

• Find out values of amplitudes, in which individual parts collided

between themselves.

• Recalculate values of amplitudes into values of angles

• Development of algorithm :

Computing of P3 (length of P3 depends on width of object :

In Object is P3 calculated according to the formula:

In Object2 is P3 calculated according to the formula:

Calculate angles:

Calculate angles:

β = β1+β2

Angles of gripper:

• Pass data into SimMehcanics

•To check if are amplitudes correct, serve function „Check in 3D plot“. This function draws lines according to dimensions of arm and according to coordinates entered from GUI.

Conclusion

AUTOMATION OF ROBOTIC ARM

Tomáš STANOVIČ

6th International Conference of young Scientists on Solutions of Applied Problems

in Control and Communications, Data Processing and Data Analysis

19.3. 2015