This is my first arduino project so please bear with my lack of knowledge.
Im building a poor mans peloton bike for my wife. I bought a relatively inexpensive exercise bike that came with an electronic display that uses a sensor to display speed. I have already figured out how to display the bike wheel resistance using a slide pot and now im trying to get cadence info. I have no idea what type of sensor this is, but it sits right next to the wheel and plugs into the display via a 3.5mm stereo jack. Taking apart the display I was able to follow the leads from the sensor to the pcb.
I hooked up a multimeter to the two sensor wires, V to red(RPM in), and COM to black(DR3). When the display is on, the multimeter reads 3.2V. If I spin the wheel the voltage will momentarily drop, once per revolution, to zero and then back to 3.2V. So it looks like I can calculate RPM if i capture that voltage drop, but I'm at a loss for how to hook this up to the arduino.
My questions are:
what kind of sensor is this?
how do i wire this to the arduino?
can somebody point me in the right direction for code to capture the voltage drop and convert it into RPM. from my tinkering it seems similar to a digital read LOW, but I'm not quite sure how to implement it.
Looks like a simple reed switch, unplug from the bike and put your Ohmmeter probes from plug tip to ring to see if the switch is normally open (closes momentarily when wheel magnet passes), or normally closed (opens momentarily when wheel magnet passes). Are you going to read it WHILE it is powered by the bike controller?
JCA34F:
Looks like a simple reed switch, unplug from the bike and put your Ohmmeter probes from plug tip to ring to see if the switch is normally open (closes momentarily when wheel magnet passes), or normally closed (opens momentarily when wheel magnet passes). Are you going to read it WHILE it is powered by the bike controller?
awesome. ohmmeter reads 1 until I hit the sweet spot, then it drops to ~1.8 on the "200" setting. I guess that means its 360 ohms and that its normally open?
No, I wasn't planning on using the meter that came with it. There's not enough room for it and an ipad. Plus, its pretty ugly and not very useful apart from the speed reading. I'm planning on hooking up a 16x2 LCD to the arduino and displaying the wheel resistance and RPM just below the handlebars.