How to make a Remote Controlled Robot Car?
The main frame of the robot is the body which holds the motor, wheels, the receiver of the remote control kit and the batteries.
Motors can be used to drive a car which uses differential turning mechanism. This is the simplest steering possible and is achieved by turning one motor on and the other motor off to achieve steering. The on and off controlling of the motors is done using a remote control.
- Remote Control Kit
The chassis is where you can really apply imagination to make it as light as possible and suitable according to the challenge.What is essential to realise is that the weight of the motors is pretty standard and cannot be reduced beyond a certain extent. In a robot with limited power supply (i.e. a battery) the power-to-weight ratio has to be kept maximum. This can be done by limiting the weight of the chassis. Chassis can be made out of:
- Wood (using right angles to attach motors, drilling and attaching the front wheel is easy)
- Plastic (not easily available, but if found makes a very light chassis).
- Metal (most common chassis which is available at Lamington Road, not recommended because the motors can get misaligned very easily resulting in poor turning).
- Duct tape (alone can be used to attach the motors to each other, makes a fairly sturdy yet light chassis)
- Plastic pipes
In a race, the lightest chassis is usually the best, whereas in a robowars kind of challenge, a heavier chassis might be advantageous.
REMOTE CONTROLLED KIT:
Making a remote control kit at the beginners level is a hard thing to do. I would suggest you go in for a readymade kit which is available online and requires no experience to run and is fairly a beginner proof.
Used for supplying power to a remote controlled car, rechargeable batteries are usually the best ones. I suggest you visit this shop called Pitambara at Lamington Road which sells only batteries. Otherwise a standard 300-500rpm motor runs well between 9V and 12V, and alkaline batteries of the brand Camelot or Zinc carbon batteries of brand Hi Watt. The appropriate series parallel combination can be used to provide more power than a standard battery can provide.
For a remote control car, we use geared DC motors. A DC motor is a low-torque, high-rpm motor which has to be geared down to reduce the speed and increase the torque. The gearing is done internally in motors available in the market. Motors convert electrical energy of the batteries to mechanical energy, which is used to drive the wheels.
Motors should be of around 300-500 rpm and can be bought for around 200 INR (4 US dollars according to the current rate) at either Hindustan Electronics or Servo Electronics, both at Lamington Road.These motors should be connected with their shafts in a line with each other such that differential turning mechanism works.
Wheels are mainly of two types in this basic car, one is the type attached to the motors at the back, which are used for steering, and another trolley (castor) wheel in front, which allows 360 degrees free rotation and avoids friction on the ground.
The wheels can be put on the shafts either by using screws or by wrapping the shaft with masking tape first.The trolley wheel and masking tape are available at any hardware shop. The other two wheels may be bought out from a good collection at servo electronics.
Links to refer online for remote-controlled toy car making tips:
General Robotics forums,good to get an idea of the scope of robotics beyond human controlled robots :
- http://groups.yahoo.com/group/booksbybibin/ (a good tutorial on basic electronics)