LabVIEW Robotics

Blind Driver Challenge from Virginia Tech: A Semi Autonomous Automobile for the Visually Impaired September 1, 2009

How 9 mechanical engineering undergrads utilized commercial off-the-shelf technology (COTS) and design HW and  SW donated from National Instruments to create a sophisticated, semi-autonomous vehicle that allows the visually impaired to perform a task that was previously thought impossible: driving a car.

Greg Jannaman (pictured in passenger seat), ME senior and team lead for the Blind Driver Challenge project at VT, was kind enough to offer some technical details on how they made this happen.

How does it work?

One of the keys to success was leveraging COTS technology, when at all possible. This meant, rather than building things from scratch, the team purchased hardware from commercial vendors that would allow them to focus on the important stuff, like how to translate visual information to a blind driver.

example of the information sent back from a LIDAR sensor

So they started with a dune buggy. They tacked on a Hokuyo laser range finder (LIDAR) to the front, which essentially pulses out a laser signal across an area in front of the vehicle and receives information regarding obstacles from  the laser signals that are bounced back. LIDAR is a lot like radar, only it uses light instead of radio waves.

For control of the vehicle, they used a CompactRIO embedded processing platform. They interfaced their sensors and vehicle actuators directly to an onboard FPGA and performed the environmental perception on the real-time 400 Mhz Power PC processor. Processing the feedback from sensors in real-time allowed the team to send immediate feedback to the driver. But the team did not have to learn how to program the FPGA in VHDL nor did they have to program the embedded processor with machine level code. Rather, they performed all programming on one software development platform; LabVIEW. This enabled 9 ME’s to become embedded programmers on the spot.

But how do you send visual feedback to someone who does not see? You use their other senses. Mainly, the sense of touch and the sense of hearing. The driver wears a vest that contains vibrating motors, much like the motors you would find in your PS2 controller (this is called haptic feedback, for anyone interested). The CompactRIO makes the vest vibrate to notify the driver of obstacle proximity and to regulate speed, just like a car racing video game. The driver also wears a set of head phones. By sending a series of clicks to the left and right ear phones, the driver uses the audible feedback to navigate around the detected obstacles.

The team has already hosted numerous blind drivers to test the vehicle. The test runs have been so successful, they’re having ask drivers to refrain from performing donuts in the parking lot. And they already have some incredible plans on how to improve the vehicle even further. Watch the video to find out more about the project and learn about their plans to further incorporate haptic feedback.