Embedded Motion Control 2018 Group 7: Difference between revisions

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By the use of a corner detection program the exit is determined in the room. PICO aligns with the angle at which the exit is detected and will drive forward. A potential field must make sure that PICO does not hit any walls.
By the use of a corner detection program the exit is determined in the room. PICO aligns with the angle at which the exit is detected and will drive forward. A potential field must make sure that PICO does not hit any walls.


 
[[File:Pico_escape_room.gif ||thumb|upright=2|right|Figure 1 Animation of the Escape room challenge]]


=== Potential field method ===
=== Potential field method ===

Revision as of 14:22, 30 May 2018

Group Members

TU/e Number Name E-mail
0833049 Sam Roovers s dot roovers at student dot tue dot nl
0886654 Siebrand Keja s dot c dot keja at student dot tue dot nl
1022624 Milan Haverlag m dot a dot haverlag at student dot tue dot nl
1279637 Piyush George Alexander p dot g dot alexander at student dot tue dot nl












Initial Design

The Initial Design document can be found here : File:Emc-designrequirements.pdf

Simulation for the Escape room challenge is shown below.

Figure 1 Animation of the Escape room challenge

Escape room competition

By the use of a corner detection program the exit is determined in the room. PICO aligns with the angle at which the exit is detected and will drive forward. A potential field must make sure that PICO does not hit any walls.

Figure 1 Animation of the Escape room challenge

Potential field method

In order to prevent PICO from crashing into the walls, obstacle avoidance is needed. For this it is chosen to implement potential field method. The potential field method works by combining a attractive force towards a desired set-point with repulsive forces generated from obstacles.

The Attractive force is calculated from the distance between the robot and the set-point. [math]\displaystyle{ r_{att} = \sqrt{(x_{set}-x_{PICO})^2+(y_{set}-y_{PICO})^2} }[/math] and the angle: [math]\displaystyle{ \alpha_{att} = tan(\frac{x_{set}-x_{PICO}}{y_{set}-y_{PICO}}) }[/math]

The attractive force is calculated using a proportional controller:

[math]\displaystyle{ F_{att} = r_{att}*K_{att} }[/math]

The repulsive forces are calculated by taking the inverse of the distance to the wall measured with the laser range finder with the following formula: [math]\displaystyle{ r_{rep}(i) = \sqrt{(x_{wall}(i)-x_{PICO})^2+(y_{wall}(i)-y_{PICO})^2} }[/math] [math]\displaystyle{ F_{rep}(i) = \frac{K_{rep}}{r_{rep}(i)^3} }[/math]

The attractive and repulsive forces are then split in their x and y parts. Their respective x an y parts are then added together:

[math]\displaystyle{ F_{tot}(x) = F_{att}(x) + \sum{F_{rep}(i)(x)} }[/math] [math]\displaystyle{ F_{tot}(y) = F_{att}(y) + \sum{F_{rep}(i)(y)} }[/math]

These Forces are then used to determine where PICO should drive to.