Let's Make Robots!

crash question

how do you awoid that your robot drive over the cleff, or down the stairs?

Cant find any solution, as it have to know that the edge is there in time to either stop, or drive around it. And right now i cant see any way that ultrasonic, IR or any other sensor that can detect that kind of ting from a distance.

Any1 know how to solve this?

Damn those LCDs

Rightyo, sparkfun 16x2 serial lcd hooked up to 3.3v, gnd, and the tx pin on my arduino. I just want an example of really basic code that will print something on the lcd, i've searched the arduino site and google but none of the tutorials seem to make sense. is the move to x character command necessary? I just want print like the values from a sensor or what not which seems easy if i could just have it print something simple.


 this is my code:

Project: graphing with graphical LCD using microcontroller

anyone knows what LCd best suits my project?.. the project goes like this: An LCD will dipslay a graph of temperature profile of a heater -- that is, a thermocouple connected to the heater sends signals to the microcontroller and the microcontroller must send signals to the LCD to graph the temperature versus time line graph.

If anyone knows, how should the program go?..please help me

L293D motor driver and Tamiya 70097

hi all i bought a Tamiya 70097 Twin-Motor Gearbox but the motors don't spin when used with a L293D driver IC but it works ok when it connects directly to the barrery (5v). i have a different 6v motor which works fine with the driver IC so i know it should work.

servo misbehaving without a control signal... :(

hi all, I'm trying to control some servos (Turnigy TG9e) using an Arduino. I use external power for the servos (5V, 3Amp), and keep the grounds together.

 the problem is that during RESET (or startup), the servos jumps fast to an out-of-range dangerous zone...

I tried adding resistors any many places (from the control pin to the ground, in between the control pin and the servo, and even between the control pin and the positive terminal) - didn't help.

Total beginner with a PIC question

Right so Im a trainee at the university as a technician..


Work's have provided me with a University made microcontroller board with a PIC18F4520 on it...


Im a total newb with electronics and Im finding it hard getting to grips with this board, I really want to follow the tutorial with the 85$ robot and for that it requires a PICAXE board...


Super Basic

Hey guys, I am a Product Design Engineering student at Glasgow University / Glasgow School of Art, and we just got our project brief for this semester. In groups we have to make a multi-purpose vehicle that competes in a series of challenges, in a sort of 'Vehicle Olympics'. So, the challenges are:

1) Hill climb - 20m track up a steep hill. Simple time trial.

2) Tug of War - Vehicles will be tied back to back, on a Vaseline-covered area. First robot to get further, or out the ring wins

Ultrasonic sensors and pets

Hey all. I'm thinking about building my first robot. Was hoping to build some kind of wheeled monstrosity with lots of sensors, but I beginning to think using ultrasonic sensors might not be a good idea with a cat in the apartment. Does anyone know how pets react to the ultrasonic signals?

Servo torque question

I'm planning to build a robotic arm and need to know what servos to use.
Can someone tell me if my math is correct here?

When i take a servo that has a torque of 240 oz-in (17 kg-cm) and use that as shoulder joint.
A 20 cm long arm would be able to lift a maximum of 17 / 20 = 0.85 kg ?