Design Report

Bugbot

Frame 

The assignment was to find a frame that could rotate on its own ax. This was needed because to work with a design that could rotate on its own ax, it was easy to make the 90 degrees angle. And with the frame like this is easy to program because you only have to steer with the engine and you don’t need to steer with a separated steer because the engines will. This is easy to make because only two wheels are needed that can rotate in both directions and one free wheel that doesn’t as an engine and can steer free.

Because one of the team members already had a frame like this at home it saved a lot of time to use this frame.

The frame to use was 25 cm long, 15 cm width, and is 7 cm high. The shape of the frame is oval and already has two engines + wheels. The wheel at the back was also already on the car so we didn’t had to do anything about how we where going to move the car around.

H-bridge

The engines where already on the car, so the next assignment was to make the engines turn with a 5 Volt signal. This is because the engines have to react to the signal that is coming out of the microcontroller. This signal is 5 and  0 Volts. To make the engine turn in both directions the H-bridge is used.

there are two engines so we had to make this print twice. And because we wanted to separate the engines from the microcontroller so they couldn’t interfere with each other we used optocouplers. With this the two systems couldn’t interfere with each other and we have less problems.

This is the testing print of the H-bridge, we are using this print now as our originally print, we didn’t had the time to make a real print. The H-bridge print is at the back of the car near the engine. The print is 10cm long and 8 cm width, the print is inside a plastic box and has and off/on switch for the power supply  of the engines.

Object detection

The object detection works with the reflection of sound. One speaker emits the sound and the other one receives the signal. If the signal is reflected the print emits a signal. On the vehicle there are three object detectors, one in the front one on the right and one on the left side. Because there was not enough space in the front, there has been decided to attach the prints at the back of the car. The speakers are in the front of the car so the vehicle detects the objects ahead of it.

The prints at the back of the car are 5 cm long and 4 cm width and are attached to the spoiler of the car. The speakers are on the front of the car inside the holes in a plastic plate. The speakers couldn’t detect the right and the left side so the plastic plate was bend so the detectors can see these directions too.

Line detection

Because the car had to detect a silver line the line detection was necessary. The line is detected whit a LDR and a power LED. The LED emits an amount of light, because an amount of light is reflected on the floor towards the LDR it has a value. When the LDR and the LED are above the silver line, more light is reflected and the LDR has another value. Depending on this value the line is detected or not. Because the car must know when a angle in the line is coming the detectors are in the front of the car.   

The total electric model looks like this, the test print was made for this line detection and again there wasn’t enough time to make a real print.

 The print is placed at the front of the car near the detectors itself and is 12 cm width and 4 cm long.

There are two indication led’s on the print to show which one of the detectors detect the line. On both side’s there are changeable resistors to focus the detectors when to switch. 

Infrared detection