INTELLIGENT AUTONOMOUS SYSTEMS LAB

DODICHA project for the development of a

multipurpose agricultural robot

IAS-LAB

The project is founded

by local government of

Regione Veneto with

the FEASR program for

the development of

Project introduction

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the development of

rural areas and

agricultural

technologies.

The DODICH project’s aim is to develop a multipurpose robot capable

to perform simple tasks on a vineyard, like spraying chemicals.

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Partners

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The prototype robot platform created

by Giorgio Pantano

The prototype robot platform created

by UNIPD

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hardware – sensors - softwares

Current robot setup

The prototype robot platform created

by Giorgio Pantano

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IAS-LAB

• Autonomous navigation of a

wheeled robot in a generic

vineyard with a laser scanner

Objectives (1)

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IAS-LAB

• Autonomous navigation of a

wheeled robot in a generic

vineyard with a laser scanner

• Automatic identification of

plants to enable or disable the

Objectives (2)

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plants to enable or disable the

spraying implement

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• Autonomous navigation of a

wheeled robot in a generic

vineyard with a laser scanner

• Automatic identification of

plants to enable or disable the

Objectives (3)

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plants to enable or disable the

spraying implement

• Investigation of a wireless self-

charging system for an

electrical powered robot

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• Autonomous navigation of a

wheeled robot in a generic

vineyard with a laserscanner

• Automatic identification of

plants to enable or disable the

Objectives (4)

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plants to enable or disable the

spraying implement

• Investigation of a wireless self-

charging system for an

electrical powered robot

• Development of a GUI that

enable the user to define a

navigation path for the robot

over the vineyard’s GIS map

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The wireless charging system overiew

Solar panels

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Wireless charging overview

The power source can provide up

to 4kW of power, its output to the

field coil is an AC current with a

frequency of 100kHz.

The pick-up coil intercepts the

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The pick-up coil intercepts the

generated magnetic field and the

generated current is rectified by a

rectifying circuit* which output is

connected to the robot’s battery

charger.

*Naik et al. (2013, September). Design of a contact- less battery charging system. In AFRICON, 2013 (pp. 1-6). IEEE.

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Wireless charging overview

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The robot setup

The robot is equipped with a

personalized fixed structure to support

the onboard laptop and to attach the

sensors.

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sensors.

The sensors used are:

• The RGB camera of an ASUS Xtion to

detect the marker position

• An Hokuyo 2D laser-scanner to detect

the wall line

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1. The marker pose is estimated with

the calibrated RGB camera

2. The wall line is extracted from the

laser-scanner data

3. We project the marker point on the

Sensor fusion for robot localization

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3. We project the marker point on the

wall line, obtaining a 2D local map

and the localization of the robot in

respect to the marker

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1. The marker pose is

estimated with the

calibrated RGB

Sensor fusion for robot localization

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calibrated RGB

camera

2. The wall line is

extracted from the

laser-scanner data

3. We project the marker point on the wall line, obtaining a 2D

local map and the localization of the robot in respect to the

marker

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We used the motion planning algorithm by Park et al.*.

The input to the algorithm are the distance and the different direction

angles between the robot’s center, the target position and the desired

orientation -> directly from the localization.

With its parameters it is easy to tune for a graceful curve:

The egocentric motion planner

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With its parameters it is easy to tune for a graceful curve:

*Park et al. “A smooth control law for graceful motion of differential wheeled mobile robots in 2D environment”. Robotics and Automa-

tion (ICRA), 2011 IEEE International Conference on (pp. 4896-4902). IEEE.

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The charging system’s efficiency depend on the load applied:

• When transferring 35W (what is needed by our robot) the absorbedpower is 80W -> 43% of efficiency

• When transferring 78W the absorbed power is 125 W -> 62% of efficiency

So there is a no-load absorbed power of 43W, which means that the

Efficiency of the wireless charging system

System overall performances

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So there is a no-load absorbed power of 43W, which means that the efficiency of the coil system is in both cases 94%.

Remind that the power source is designed to provide 4kW. A tailored generator will be far more efficient.

With a misalignment of 2cm the efficiency loss is about 5%

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Precision of the docking algorithm

System overall performances

From ten random initial poses (manually measured) we evaluated the

final alignment error by measuring the segments CA, PA and CP

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Conclusions

The implemented parts of Dodich prototype:

• Autonomous navigation

• Autonomous spraying on/off

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• Autonomous docking

• Wireless recharging to

renewable energy sources

• GIS graphical user interface

for path definition