Small Mobile Robotics Platform
Introduction
Here we describe the small mobile Robotics Platform that our research group developed, including its hardware and software components.
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Our platform is relatively cheap compare to other platforms such as Pioneer. The platform consists basically of an iRobot Create and a small computer mounted on top of it.
We use the battery provide by the iRobot Create to power the small computer. Currently, we are using the Advanced Power System (APS) which provides a capacity of 3Ah.
Hardware
Computer
The ebox-3854 is a 800MHz embedded PC, with 256MB shared DDR, up to 1280x1024 VGA, 1x10/100 LAN with PXE6xUSB 2.0, Mini PCI socket, Fanless design, Rear-accessible CF slot (IDE only). Since the ebox does not have serial, we need a USB to Serial Adapter to connect the ebox to iRobot Create.
Storage
The ebox-3854 does not have a hard disk. We chose a 4GB compact flash(CF) card. It is also possible to attach an external hard disk through USB.
Power Supply
The iRobot Create battery has 14.4V DC but the ebox3854 needs 5DC voltage. We need a DC-DC converter. Ituner Networks Corp. manufactures a tiny DC-DC adapters called picoPSU. The picoPSU-60WI is wide input adapter that takes any voltage from 6 to 26V. To be able to use picoPSU-60WI without a ATX board, you need to connect two pins. Turn picoPSU vertically, with extra connectoron the right side. Connect pin 3 from left side to pin 4 on the right side .
Power Connector
We are powering the computer using the Create’s battery. We followed the design of SmURV Robotics Platform .
Wireless
We chose a wireless card that support 802.11 a/b/g because the robots should be able to connect to our Wireless Mesh Testbed. The device is the EMP-8602 6G: 802.11a/b/g 400mW High Power mini PCI Card. More details at the Bill of Materials and Software Sections.
Assembly
We soldered the db25-connector with wires and to the DC-DC Convert. Pins 10,11,12 provide battery power. Pins 16,21,25 provide battery ground.
We attached the ebox to iRobot Create with Velcro.
Bill of Materials
| Part | Name | Cost in US$ | Available at |
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| Robot | iRobot Create Premium Development Package, also includes APS, virtual walls and remote control | 299.99 | iRobot |
| Computer | eBox-3854 | 250.00 | WDL Systems |
| Power Cable | eBox Power Cable | 7.00 | WDL Systems |
| Storage | A-DATA 4GB CF(120X) | 36.99 | newegg.com |
| DC-DC Power Supply | picoPSU-60WI | 54.95 | mini-box.com |
| Power Connector | D-Sub 25 connector and hood (part #276-1547 and #276-1549), male DC jack (part #274-1573), some hookup wire (18 or 20 gauge) | 7.50 | radioshack.com |
| USB to Serial Adapter | SW-1301 | 12.45 | sewelldirect.com |
| Wireless Card | EMP-8602 | 58.00 | netgate.com |
| Pigtail | PIG-UFL-RPSMA | 14.00 | netgate.com |
| Antenna | RD2458-5-RSMA | 12.30 | connexwireless.com |
Software
Our project uses Fedora Core 6 as the Operating System.
The player software from The Player Project controls the robot. The latest player software from CVS, Player CVS Code , has a driver for create.
For the Wireless Card, we recommend the Madwifi Device Driver .
Related Work
Microsoft developed a Sumo Robot similar to our design. There are two main differences compare to our design. Microsoft used ebox2300 instead of ebox 3454. They also needed an extra battery instead of using the iRobot Create battery. More information at: Microsoft Sumo Robot.
The Brown Robotics Group has an interesting webpage explaining their SmURV Robotics Platform design.
Related material provide by iRobot: