3

CAN I HACK IT?

A radio-controlled car

Can a radio-controlled car be hacked to work with a microcontroller?

YOU’LL NEED

Nikko 9018

Velocitrax radio-

controlled car

COST

£29.99

WHERE

amazon.co.uk

adio-controlled cars, tanks, and

ponies have been a staple of

children’s play for decades. They

enable children to control scale

models of real-world vehicles and

create motorised play sessions.

For parents, radio-controlled toys typically meant

batteries... lots of batteries! But in recent years we

have seen better-quality radio-controlled vehicles

at much cheaper prices. So what can you get for

around £30 for consumer-level tech, and how can

we hack it? Let’s find out.

GENERAL CONSTRUCTION

The Nikko 9018 Velocitrax car is made from a

generally firm plastic, with some softer plastic

sections typically used to absorb impact. The plastic

used is easy to work with, so hacks involving rotary

tools, drills, and hand tools are possible.

Measuring approximately 29 cm by 16 cm and

12 cm tall, the car is big enough to easily work with

and inside it has plenty of space to add further hacks.

A tank-track-style tread enables the car to cover

most terrains. Power comes from the rear wheels,

which means that the front wheels are merely there

to complete the tracks and provide adequate tension.

Standard crosshead screws hold the shell to the

chassis of the car, and only six screws need to be

removed in order to gain access to the insides.

BATTERY POWER

Radio-controlled vehicles have come a long way since

those early battery-eating monsters! These days we

find a 7.2 V Nickel-metal hydride (NiMH) battery rated

at 700 mAh. In tests we found that the battery was

reporting as 8.1 V after a fresh charge. The battery

connects to the car using a bespoke connector that

physically prevents reverse polarity connection.

The battery is charged by removing it from

the car and connecting to the

supplied charger unit; charging

times are around one hour.

MOTORS

There are two motors

at the rear of the car;

these run at 7.9 V

and provide both

forwards and backwards

movement. Each motor

comes with three 100 nF

ceramic capacitors (104) used

to smooth the current flowing to the

motors. The motors provide plenty of power for

the car; in fact, they are a little too powerful for the

size and weight of the car and it is liable to perform

wheelies when starting. When first started, the

motors will pull a quick 2.2 A, before settling down

A radio-controlled car?

Can I Hack It?

R

Right

Lean, mean, and a

shocking shade of

green. Sure, it might

not be the prettiest

colour, but we have

a great all-terrain

vehicle in a cost-

effective package,

so we can always

spray-paint it!

Les Pounder

@biglesp

Les Pounder is a maker

and author who works

with the Raspberry Pi

Foundation to deliver

Picademy. He also

helps teachers/learners

to become creative

technologists. He blogs

at bigl.es