Intelligent Side Stand

Side stand in a motorbike is quite dangerous and yet inevitable. Nowadays the bikes are coming equipped with side stand indicators, each make having its own design.

Bajaj Pulsar uses magnets to toggle a switch. This mechanism cannot be easily ported to other bikes because modifications are required to the side stand as well as the bike. (One magnet needs to be fixed to the stand and another magnet to the bike). This is not trivial because of mechanical constraints.

TVS Scooty uses a mechanical switch which suffers from the same drawback as above.

I now propose a design which can be easily installed on any bike. I attach a small box with dimensions 3cm * 3cm * 3cm or smaller to the stand with three wires protruding from it.

Wire 1: Supply Voltage (12V which is the standard bike battery voltage)
Wire 2: Ground
Wire 3: Output (5V if stand is extended and ~ 0V if it is retracted)

Furthermore this design can be embedded into the stand itself for future models. In essence the stand can tell its position without any help from the bike. (In above two designs, the bike and the stand interact to determine the status of the stand). The stand can be conceptualized as an entity with three wires protruding from it as described above and hence the name Intelligent side stand.

Advantages:
1. Easy to install.
2. Zero maintenence
3. Low cost

Disadvantages:
1. The device consumes a small amount of power when the battery is turned on. But the power consumption is negligible (equivalent to one led).

The Design :

The box consists of an led, a phototransistor and a ball bearing. The phototransistor and the led are placed facing each other on either side of a hollow cylinder in which the ball bearing is free to move. This arrangement is fixed to the stand such that the hollow cylinder is at an angle to the stand. This angle is approximately 45 degrees.
Let us label the ends of the hollow cylinder as A and B. End A(or B) consists of the phototransistor and led arrangement.

1. When the stand is extended, end A will be closer to the ground and thus the ball bearing's stable state is end A(or B), thus obstructing(or allowing) the light from led to fall on the phototransistor.
2. When the stand is retracted, end B will be closer to the ground and thus the ball bearing's stable state is end B(or A), thus allowing(or obstructing) the light from led to fall on the phototransistor.


These two states can be used to control the state of the output to be either low(typically 0V) or high(typically 5V)