"Hotter/Colder" Talking Temp Sensor

This builds on my previous 'Phrasealator' blog by having a PICAXE microcontroller control the SpeakJet voice synthesizer without a PC. I wanted to get familiar with I2C, a serial inter integrated circuit serial protocol commonly used so microprocessors can read data from any sensor 'on the I2C bus'. The sensor I used was TMP102, a Texas Instruments temperature sensor (available from SparkFun). It is a low power device, the whole circuit (excluding the amplified speakers) drew only 3mA. The basic code was less than 40 lines. In operation, the system compares the current temperature measurement to the last one, and if it has changed over a degree, it speaks either "hotter" or "colder". I used the free SpeakJet Phrasealator application to generate a phoenetic string, which I cut and pasted into my basic code. Its dictionary contained the word "hot", to which I added "AXRR" to get the 'ger' of "hotter".

hotter  \HE\OH\TT\AXRR = (20,96,21,114,22,88,23,5,6,183,136,191,151)

Video [Link]

Circuit Diagram [Link]

Basic Code [Link]

SparkFun [Link]

Parts List [Link]

My other interests (Kayaking, plant identification, etc.) [Link]

Robot 3: Autonomous Sensor Platform 'Jimbo'

This is my first autonomous robot (he has a mind of his own!) And boy, what a wayward child he's been!
I built this to explore various sensors and sensor interfacing to the PICAXE-18M2 micro-controller.
His mission is to search for a magnet using Hall-Effect sensors, and to avoid obstacles like walls and cliffs using reflective IR (infra-red) sensors. When he encounters an obstacle, he has to stop, back up, turn a random angle, and proceed forward again until he finds the magnet. When the prize if found, he stops and blinks a green LED. It took 4 tweeks of the program to get it right.

Instructables Blog [Link]

Video of Robot in Action [Link]


My other interests (kayaking, plant identification, sea beans, etc.) [Link]

Survey of Sensors

A remote-controlled robot relies 100% upon the operators senses. For an autonomous or semi-autonomous robot, we need to impart awareness of its environment. Even for a robot that is not autonomous, telemetry of sensor data can be valuable. In this blog, I surveyed the low-hanging fruit of the abundance of inexpensive sensors. The average cost per sensor is $12. Almost anything you can imagine can be measured: proximity, distance, temperature, light, magnetism, sound, barometric pressure, vibration, etc. I am really tempted to combine a bunch of sensors and construct a tricorder (like on Star Trek) for the Ghost Adventures show. (Can a spirit actuate a capacitive touch sensor?)


Sensor survey matrix: [Link]

My other stuff (kayaking, plant ID, sea beans, etc.): [Link]