ActivMedia Robotics

provides very reliable links; radio modem-mediated communication is much less reliable. Accordingly, when designing client applications that may use radio modems, do not expect to receive every information packet intact, nor can you expect the server to accept every command.

Table 4. Standard P2OS Server Information Packet (SIP)

Name

Data Type

Description

Header

integer

Exactly 0xFA, 0xFB

Byte Count

byte

Number of data bytes + 2 (checksum); must be

 

 

less than 201 (0xC9)

Status/Packet

byte = 0x3S; where S =

Motors status

Type

2

Motors stopped

 

3

Robot moving

Xpos

unsigned integer (15 ls-bits)

Wheel-encoder integrated coordinates; platform-

 

 

dependent units; multiply by DistConvFactor‡

Ypos

unsigned integer (15 ls-bits)

to convert to millimeters.

Th pos

signed integer

Orientation in platform-dependent units—

 

 

multiply by AngleConvFactor‡ for degrees.

L vel

signed integer

Wheel velocities (respectively Left and Right)

 

 

in platform-dependent units;

R vel

signed integer

multiply by VelConvFactor‡—currently 1.0 for

 

 

all—to convert into millimeters per second.

Battery

byte

Battery charge in tenths of volts

Stall and

integer

Motor stall and bumper accessory indicators. Bit

Bumpers

 

0 of the lsbyte is the left wheel stall indicator =

 

 

1 if stalled. Bits 1-5 of that same byte

 

 

correspond to the bump switch states (1=on) for

 

 

the rear bumpers accessory. Bit 0 of the msbyte

 

 

is the right wheel stall; the bits 1-5 of that same

 

 

msbyte correspond to the front bumpers switch

 

 

states.

Control

signed integer

Setpoint of the server’s angular position servo—

 

 

multiply by AngleConvFactor‡ for degrees

FLAGS

unsigned integer

b0 – motors flag (1=motors enabled)

(was PTU)

 

b1 – sonar flag: enabled if 1.

Compass

byte

Compass heading in 2-degree units

Sonar

byte

Number of new sonar readings included in

readings

 

information packet; readings follow:

Sonar

byte

Sonar number

number

 

 

Sonar

unsigned integer

Sonar range; multiply by RangeConvFactor‡—

range

 

currently 0.268 for all—for millimeters

…rest of the sonar readings…

 

 

 

 

Timer

unsigned int

Selected analog port number 1-5

Analog

byte

User Analog input (0-255=0-5 VDC) reading on

 

 

selected port

Digin

byte

User I/O digital input

Digout

byte

User I/O digital output

Checksum

integer

Checksum (see previous section)

‡Factors see Table 17 Appendix D and Saphira’s parameter definition file for your robot

Because of the real-time nature of the client/server interaction, we made a conscious decision to provide an unacknowledged packet interface. Re-transmitting server information or command packets would serve no useful purpose, because old data would be virtually useless in maintaining responsive client-server interaction.

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Pioneer 2 / PeopleBot manual Name Data Type Description
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2 / PeopleBot specifications

Pioneer 2, also known as PeopleBot, is an advanced mobile robot platform heralded for its versatile design and robust capabilities. Developed by the renowned robotics company Adept Technology, Pioneer 2 has become a staple in the field of mobile robotics, widely utilized for research, education, and practical applications in various industries.

One of the standout features of Pioneer 2 is its exceptional mobility. The robot is equipped with differential steering, allowing it to navigate complex environments with precision. Its compact and sturdy chassis enables it to traverse a variety of terrains, making it suitable for indoor and outdoor exploration. This mobility is further enhanced by an adaptable wheel configuration, allowing for smooth movement even over obstacles.

In terms of technologies, Pioneer 2 is outfitted with an array of sensors that facilitate autonomous navigation and obstacle avoidance. These sensors include laser range finders, infrared sensors, and bumpers, which work in tandem to map the surrounding environment and detect potential hazards. This capability is critical for applications in areas such as warehouse automation or reconnaissance tasks, where safe navigation is paramount.

Pioneer 2 also supports extensive software frameworks, notably the Robot Operating System (ROS). This compatibility allows researchers and developers to leverage a vast library of tools and algorithms, expediting the process of programming and deploying robotic applications. Additionally, the platform can be integrated with various payloads, such as cameras or grippers, expanding its functionality further.

Another significant characteristic of Pioneer 2 is its user-friendly design. The robot comes with an easy-to-use programming interface that empowers users with varying levels of expertise to engage with the technology. Educational institutions often employ Pioneer 2 in robotics courses to provide students with hands-on experience in programming and operating robotic systems.

Powering Pioneer 2 is a rechargeable battery system that ensures extended operation times. This feature is particularly advantageous for fieldwork applications where connectivity to a power source may not be readily available. Importantly, the robot’s modular design facilitates maintenance and upgrades, allowing users to keep their systems current with advances in technology.

Overall, Pioneer 2 (PeopleBot) exemplifies innovation in mobile robotics with its outstanding mobility, advanced sensing technologies, compatibility with leading software frameworks, and a design focused on ease of use and adaptability. It continues to be a preferred choice for researchers, educators, and professionals in the rapidly evolving landscape of robotics.
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