Among the three platforms, the ATRV-Jr from iRobotTM is an all-terrain mobile robot, the only system purchased as a whole because it is commercially designed for the purpose of research and development. Shown in figure 1,the robot has an on-board computer, a suite of sensors (including a compass, a sonar array, a high-performance vision system with pantilt-zoom control, an inertial navigation system, a differential GPS system), a wireless/radio system (including a base station, a mobile station, and antennas), and safety devices (tactile bumpers, an emergency system, and backup units).

The second robotic platform consists of 6 all-wheel-drive rovers shown in figures 2 and 3, a group shot and a close-up image. These mini rovers are equipped with a 4-axis microcontroller, a fast wireless communication module unit, an optical encoder, a digital compass, and a micro inertia measurement unit (for 3 out of 6 rovers). A mini gripper can also be installed. To reduce size, weight and development cost and to increase flexibility, the rovers are not made to be truly autonomous themselves, instead they are wirelessly controlled by a host computer. In the host computer, information of individual rovers are shared according to their appropriate trajectory planning and control algorithms. For example, in simulating a dynamic and uncertain environment, a few of the rovers are designated to play the role of "moving obstacles," these "obstacles" are controlled open-loop according to any prescribed trajectories. The trajectories of the "obstacles" are not available to any robotic vehicles, the current position and velocity of an "obstacle" (or one rover) are passed to a specific rover only if it enters into the "sensing" range of the rover, and the rover replants its trajectory (and/or changes its control) to account for the "uncertainty." By enabling the control of feedback information, the host computer creates whatever environment is designed, simultaneously and independently undertakes the planning and control functions of each rover, and becomes the arbiter in quantifying the overall system performance.

To simulate many applications in manufacturing automation, a cylindrical robotic manipulator was designed and assembled. As shown in this figure 6, cylindrical robotic manipulator has 3 degrees of freedom (two translational and one rotational) and a gripper as the end effector. It is controlled by a host computer with a PCI-7344 motion controller card from National Instrument. It is built using off-the-shelf components (Galil servo motors, PWM power amplifiers with torque-control mode, Lintech manipulator, standard camera).