Lola, the Mobile Robot from NC State

Abstract

Lola is a Nomad 200 with a standard l6-transducer sonar ring and tactile bumper sensors. We have taken advantage of the Nomad’s modularity and moved 3 of the rear sonars to the front just above the bumper. This provides Lola with the ability t, o sense chairs and other potential obstacles that might otherwise be unseen. Lola’s main processor is a 486DX2-66 running Linux (Unix). The combination of Linux and wireless Ethernet makes code development on Lola a real joy. That is, from any workstation on the network (including the Internet) we can telnet to Lola and export the display for developing, debugging and executing code while monitoring Lola’s status during operation, which beats having to wheel around a terminal and extension cord. The idea is to do all development without leaving your chair. The vision hardware consists of an on-board image processor and a single RGB camera mounted on a pan/tilt unit. Lola’s image processor was purchased from Traquair Data Systems and is blessed with two ‘C40 DSP’s running in parallel. Performing all computation on-board has several advantages: the video data is not corrupted by radio transmission noise, commands are not lost, and there is no communication lag that may result in Lola crashing into things. These findings are consistent with those of previous competitors. On the downside, the on-board image processor contributes significantly to the battery drain, which is partly due to its intended desktop use. Still, we are able to get about 2 hours of operation per charge.