Okay so I have built a bike with sensors to measure the speed of the bike and the torque input by the rider and I want to output Power. I have a linear potentiometer to measure the torque with an analog signal, I have an encoder measuring the speed with a digital signal, and I want to output an analog Power signal that ranges between 0.8 to 3.5 VDC. So I want to measure an analog and digital signal and output an analog signal. Can it be done HELP?
Stationary bike? Racing Bike, mountain bike? Do you want to make a program on your PC, an Arduino or a Cray...
Do you want to display on a PC monitor?... a little LCD screen strapped to an Arduino? or a Hologram? .... or just send the data somewhere...
I could do the project -- after I looked at what you have done and decided what I wanted to do. That might differ from your view...
Better provide a few more details.
It is a mountain bike with an electric motor. The bike works by measuring the input torque of the rider and the speed. I do want to make a program on my PC just a basic program that will multiply the two input signals to give the output.
I have been looking at Arduino by I can only find ones that have digital and PWM outputs but I was hoping to have a straight analog output rather than modify the PWM to give an analog.
I don't want to display anything all i want it to do is run the motor with the same amount of power that the rider is inputing into the bike. I want to give an output of 0.8 to 3.5 volts that will be fed into a controller. currently the controller is reading a 0.8 to 3.5V signal from a throttle but we want to fake the controller out with the signals to give an analog output comparable to the riders input.
I have been looking at Arduino by I can only find ones that have digital and PWM outputs but I was hoping to have a straight analog output rather than modify the PWM to give an analog.
Obtaining a true analog output from the arduino's analogWrite() pwm command is not real difficult but it does require some external components. First a low pass filter is used, which can be as simple a resistor from the pwm pin to a capacitor then to ground. The analog signal is then avalible at the junction of the resistor/cap connection. This will then be a true 0-5vdc analog signal. Now depending on what you want to drive with this signal you may require a opamp stage to increase current drive and or add gain to the opamp stage for higher then 0-5vdc output range. I've used a 5k resistor and a 10ufd cap and it seemed to work fine.
Lefty