Specifications and Controls

PeopleBot Sensors and Emergency STOP

Performance PeopleBot’s tabletop sensors are very reliable diffuse IR detectors mounted to the front of the robot and which detect obstacles, particularly tabletops or rope barriers, that otherwise aren’t detected by the sonars. The tabletop IR detectors respond to any surface except glass or other mirrored surfaces, and can detect objects as thin as a human finger. They are oriented to trigger when an object is 28 cm (11.5 inches) or nearer to the front of the robot and 3.75 cm (1.5 inches) at the height of the lower deck.

Two “breakbeam” IR sensors, one on each side 3.75 cm (1.5 inches) forward of the left and right column struts and between the top and lower Decks of the Performance PeopleBot, sense objects which intrude into the robot’s profile, but which may not be otherwise detected by the sonars or tabletop IR sensors.

Since the tabletop and breakbeam IR sensors are connected to User I/O digital ports, their states are communicated from the P2OS server to a connected client, such as Saphira, in the standard Server Information Packet. See the . IOpac packet contents

Pioneer 2 Arm-related SIPs and Commands

Please consult the Pioneer 2 Arm Manual for details.

Performance PeopleBot IRs sections in Chapter 6 and in Appendix A for details.

The Performance PeopleBot contains a large, red Emergency STOP button prominently positioned on the left column just beneath the upper Deck. When pressed, the button physically disconnects power from the motors and electrically shorts them to brake the motors. A separate digital sense line to the microcontroller can activate an emergency stop process in P2OS. See E_STOP and E_STALL in Chapter 6 for details. To release the Emergency STOP button, press it in and twist.

Safety Watchdogs and Configuration

Pioneer 2’s and PeopleBot’s standard onboard software, P2OS, contains a communications watchdog that will halt motion if communications between a client computer and the server are disrupted for a set time interval, nominally two seconds (watchdog parameter). The robot will automatically resume activity, including motion, as soon as communications are restored.

P2OS also contains a stall monitor. If the drive exerts a PWM pulse that equals or exceeds a configurable level and the wheels fail to turn (stallval), motor power is cut off for a configurable amount of time (stallwait). The server software also notifies the client which motor is stalled. When the stallwait time elapses, motor power automatically switches back ON and motion continues under server control.

All these “failsafe” mechanisms help ensure that your robot will not cause damage or be damaged during operation. You may reconfigure the communications, drive current, and stallwait values to suit your application. See Chapter 7, Updating & Reconfiguring P2OS, for details.

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Pioneer 2 / PeopleBot manual PeopleBot Sensors and Emergency Stop, Safety Watchdogs and Configuration

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.