Garage door opener

Attach the garage door remote control to car dashboard and make it open the door automatically when the car is close to and facing towards the garage door.

Update 26.01.2017: Hack garage door opener. Watch Sammy Kamkar.

Network simulation with threads

• One live master, two standby masters listening if there is a live master.
• Live master broadcasts every second that he is alive (hearbeat)
• If standby masters do not get heartbeat for 10 seconds, one of them randomly becomes new live master
• Optional: Gossip protocol: One standby might get the heartbear while the other can't. In that case the one that gets the hearbeat refuses the request of the other to become live master.
• Master distributes jobs to worker nodes.
• Worker nodes tell master every second that they are alive
• Worker nodes return with an answer when their job finishes. Note that job might take more than 1 second. We need one thread for heartbeat and one thread for job processing.
• GUI: Show live master, standby masters, working nodes, idle nodes, offline nodes.

Car vibration simulator for putting babies to sleep

Record car sound and vibration, replay the sound and regenerate vibration.

Fisher Price Cruisin Motion Soother
Baby Bouncer
Bouncing cradles & rockers

Fitness bike activated computer

A friend told me about a project where kids can only use the computer when they are pedalling the connected fitness bike.

How to do it: Attach a dynamo to the bike, connect it to Arduino which sends signals to computer. On the computer a program checks if the bike is active and if not, turns off display or locks the computer.

For tablets we could write an app that communicates with the RaspberryPi on the bike. We could use the same wireless design for PC.

Watermelon ripeness detector

Can be made into a smartphone app.

Correlation between sound decay rate or fundamental frequency/amplitude and ripeness.

Melon Meter

https://www.youtube.com/watch?v=LxC67dnyVGU

ppt: http://www.me.udel.edu/meeg447/98/serffiles/fall4-design-reviews/dr-ppt/dr-02.ppt

http://www.researchgate.net/publication/257798409_An_intelligent_procedure_for_watermelon_ripeness_detection_based_on_vibration_signals

Equipment:

1. Microphone
2. FFT and filtering on the Arduino
3. Ripe and unripe watermelons

increase fan rpm with temperature

Add delay to window alarm

Can I do it with analog electronics, e.g. with a capacitor? How do I discharge the capacitor? Does it discharge "slowly" by itself or do I need a resistor/LED? I probably will need a transistor too. Capacitor will be used to control the current flow via the transistor. When capacitor is fully charged, it will let current flow through the transistor which in turn activates the alarm circuit.

If I want a 10 second delay, I can achieve it with a resistance of 100K and capacitor of 100uF [see RC time constant]: tau = 100e3 * 100e-6 = 10 seconds.

https://www.youtube.com/watch?v=GeveeSTyvGs

• Capacitor: 470mF, 100mF
• Resistance: 47K, 22K
• Diode: 1N4001, 
• Transistor: 2N???

https://www.youtube.com/watch?v=LQji9_O9-aI

http://www.the12volt.com/installbay/forum_posts.asp?tid=91691

https://answers.yahoo.com/question/index?qid=20100910203520AAoZUtq

https://en.wikipedia.org/wiki/RC_circuit