194 distance sensor

[bruce273]

Nice bench ,

Got this sensor for my car but should do what you want. Could even have one half of the sensors on your wall or something aswell

eBay auction: #http://www.ebay.com.au/itm/Car-LED-4-Parking-Sensor-Reverse-backup-kit-many-color-/320670199952?pt=AU_Car_Parts_Accessories&hash=item4aa96ef090

[Chet T16]

Just bolt a length of timber to the floor in front of where you want the front wheels to stop, simples!

[Lightages]

Dave:

I have to agree with the piece of wood bolted to the floor, KISS!

And to protect your car from the inevitable bits and things being pushed off the back of the new bench, put two pieces of wood to your rafters to hold the bench up on the end and back,and then put a piece of pegboard as a back board to the new bench. Then you can hang cables and other things there out of the way too. You can never have enough storage!

[Alex]

Here, cut the top of this and glue it on the side of the supporting beam. Provides audible indication and is child friendly.

http://www.a-zara.com/images/products/d101%20large.jpg

[Chet T16]

Here, cut the top of this and glue it on the side of the supporting beam. Provides audible indication and is child friendly.

http://www.a-zara.com/images/products/d101%20large.jpg

I think the necessary impact speed may lead to "issues"

[Freighternut]

The KISS principal is totally inappropriate in this case. After all we are electronics engineers / enthusiasts.

I would go with a Ultrasonic or possibly IR sensor approach, there are plenty of options in both cases. As a side benefit, wire it into your alarm system so if somebody steals you car or, god forbid it, the bench, an alarm would be triggered.

[Rufus]

With space apparently at a premium why is so much is allocated to keeping a car a bit warmer and cleaner?

[Uncle Vernon]

With space apparently at a premium why is so much is allocated to keeping a car a bit warmer and cleaner?

Cooler too! Come Western Sydney summer, parking in a garage will equate to around 50°C lower cabin temperature. Most Aussie kids have copped Kingswood upholstery burns to the back of their legs at one time or another. It's almost considered a rite of passage.
 

[Lightages]

The KISS principal is totally inappropriate in this case. After all we are electronics engineers / enthusiasts.

In that case, he should install an ultrasonic sensor in the garage and a controller that monitors the speed of the approaching car. The controller would then send a signal out by bluetooth which would be received by a bluetooth receiver and controller in the car. The controller in the car would then apply the brakes through a servo. The controller in the garage could then smoothly apply the brakes so that the car comes to a comfortable and smooth stop every time at the same spot. The controller in the garage could also then automatically close the garage door when the car is in the correct position and turn the car off and apply the hand brake via bluetooth and servo in the car again.

The controller would then relinquish control until the next time it detects motion toward the ultrasonic sensor.

But just in case the power fails, the backup would be a piece of wood bolted to the floor.

 

[joelby]

With space apparently at a premium why is so much is allocated to keeping a car a bit warmer and cleaner?

It also saves the hassle of waking up to find your car on bricks with the wheels missing. Insurance premiums can be cheaper if your cars are kept secure.

[Freighternut]

Excellent Lightages, you are on to it!

Couple all that with a large display on the bench back board facing the driver showing entry velocity and distance to impact with the bench.
 
If the wireless auto stop system failed to stop the car, Dave having feedback from the display could hit the brakes in time to prevent demolishing the bench.

The system could be referred to as a  BDPD (Bench Demolition Prevention Device).

Cheers, Roger...

[Richard W.]

I would suggest 2 "distance sensors".

The technical one: photoelectric barrier (maybe more reliable than ultrasonic sensors)
The backup one: timber beam (if the technical solution fails...)

[James]

WORST CASE SCENARIO
Car won't start and bonnet needs to be lifted!

Anyway, nice job Dave. Besides providing you with alerts and saving the bench, a distance sensor would make a great tutorial covering the circuit design, software design (depending on the hardware), implementation and testing of the device!

James

[Dieselrunner88]

The distance sensor is a better idea than the wood blocks.  Maybe even have it count down to zero and have a warning if you go to far in.  The Idea I had for the corner of the table was to "hang" it from the roof with a small steel cable.  According to engineering toolbox 6.4 mm can handle safe load of 498kg. 

[larry104]

Low tech solution: hang a string down from the ceiling with a tennis ball at the end so the ball just touches the windshield when parked at the correct spot - I guess it's called a tennis ball car stop

[Lawsen]

The hanging tennis ball on a string was done successfully at my friend's house to warn motorists from driving into a table saw or monitor top refrigerator.  I am sure garage door electric eye sensor connected to a relay and separate lower voltage LED light to indicate the car is in the limit.  Marking painted on the side wall that lines up with a feature on the car, so not to drive it too far or into the table leg.