Arduino rover doubles up on obstacle avoidance

[Eduard Ros] wrote in show off his first attempt at building an autonomous rover (translated). As with many of these projects, he started with the base of a remote control toy truck. This solves so many mechanical issues, like steering, locomotion, and power source.

He just needed a way to control the vehicle. The recent LayerOne badge hacks either did this through the wireless controller protocol or by adding an Arduino directly to the vehicle. [Eduard] chose the latter, and also included obstacle avoidance sensors in the process. We’ve seen quite a few that use these ultrasonic rangefinders. He decided to go a different route by adding two of them rather than scanning by mounting one on a servo motor.

The video after the break shows the vehicle successfully navigating through a tight space. This makes us wonder how much data can be processed from the stationary sensors? We’re not familiar with how wide the horizontal sensitivity is on the devices. If you have some insight, please share you knowledge in the comments section.

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LayerOne badge hacking twofer

Here’s a pair of LayerOne Badge hacks that actually included the RC as intended by the badge designers.

First up, we have the autonomous RC car built by [Arko]. He calls it Stanley Jr. as an homage to the Stanford DARPA Grand Challenge vehicle. It uses an Arduino shield to add a servo with an ultrasonic rangefinder on it. The lets the vehicle drive a bit, stop and scan the horizon, then drive some more. The hope is the rangefinder will keep it from running into anything. There’s a quick test run embedded after the break.

On the right is the badge hack which [Zjpahle] finished up after the contest was already over. He also chose to go with an Arduino shield, this time it’s an IMU board. But he added a standalone Arduino board to the vehicle which drives some EL wire (ground effects) and adds IR sensors to the front of the car. The IR sensors are for obstacle avoidance, and the IMU lets him tilt his badge for direction control.

We looked at the winner of the badge hacking competition on Wednesday. That hack didn’t involve the car, but used the badge as a Morse Code beacon.

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Make your own Mindstorm sensors

[Stewart Allen] acquired a Mindstorm kit about a month ago and he’s already building his own sensors for it. He wanted a more accurate range finder with a narrower measurement field than the stock sensor. Mindstorm has the option to communicate with sensors via an I2C bus. [Stewart] set up an ATtiny45 to act as a the slave on the bus, facilitating the analog measurement of the distance voltage by using and lookup table, and handling the data transfer with the NXT brick. His testing setup is pictured above, with an AVR Dragon for programming the tiny45 and a Bus Pirate for sniffing the I2C data during the development process. The sensor, looking great on a professionally made PCB he ordered, requires a simple driver that [Stewart] hammered out for use with leJOS, the alternative Mindstorm firmware we’ve seen before.