Tilting RC Model Vehicle

This model is a 1/10 tilting vehicle with two front wheels and one rear drive; was derived from an electric model RC Arrma Vortex 1/10 which was used the aluminum chassis and removed the entire back where he had placed the electric motor and its transmission to the wheels.

Also it represent in part a my project in scale 1/1 relative to the same tilting vehicle at a variable angle in which the inclination of the front wheels, at the same time steering wheels, takes place through a system of wheels and toothed belts.

The entire rear of the model has been resized from the support of the transmission that is from toothed pulley which receives the motion from the electric motor, from this toothed pulley the motion is transmitted, through a toothed belt, to the rear driving wheel.

This aluminum support (2mm thickness) is attached to existing mounting frame with M3 screws.

Again with the aluminum of 2mm thickness were made the two levers which support the two shocks absorber and the support of the rear drive wheel; the two levers were connected with two threaded rods 3mm.

With regard to the belt transmission I have used two toothed pulleys in aluminum, the first (50 teeth), the output of the gear of the original kit, the second toothed pulley which transmits the motion to the rear drive wheel has 40 teeth and is been sized to slightly increase the number of revolutions to the drive wheel itself to try to overcome the increased friction due to the new transmission system added.

Both toothed pulleys are keyed shafts have balls bearings and their supports; also the support of the rear drive wheel is made of aluminum 1mm thick and has been obtained using the hub of the original kit which have been linked to the wishbones to connect the hub to the same lever to the left.

With regard to the front was made a triangular aluminum (2mm th.) support to connect the two gears in plastic forming tilt the model through the rigid connection of the two front shocks.

Moreover has been necessary to change the front servo (steering) 3kg-cm torque by another 9kg-cm torque due to tilting gear system that needs to lean the model.

A particular reflection is about the long wheelbase due to the rear shocks position, this creates a long steering radius, in the same time to lock the shocks on rear axle I can reduce the wheelbase but I will get another swingarm lever; I can shorten the swingarm and hence the wheelbase decreasing the shocks inclination and in the same time preloading the springs.

For the wheels I could use 1:5 RC bike wheels (Ø125mm) for its round profile but I should adapt the hubs to a bigger hole of these wheels, instead I’ve used Arrma Vortex hubs, wheels and tyres.

The next step could be to make steering also rear wheel drive, need a ball joint; moreover the author is making the body shape of this RC model but also very important could be a SERIES PRODUCTION realized by the author or by some rc toys company interested to development and making.

DIMENSIONS :
Wheelbase : 460mm; Front Track : 250mm; Overall : 570mm; Weight : Unknown

Step 1 : Start From Original Kit

Before the disassembly of the original kit I started from a design for to understand how to make a tilting and steering system and then a rear wheel drive transmission system realized by a toothbelt.

Step 2 : Front Disassembly

Disassembly of shocks and steering rods, while the aluminium front base will be straightned for to have a correct wheels geometry and need to assembly the tilting system.

Step 3 : Steering Servos

Disassembly of steering servos place and its leverage for to assembly a linking with front gears tilting system.

Step 4 : Electronic Parts Disssembly

Disassembly of receiver, electronic speed controller and motor wires.

Step 5 : Electric Motor and Transmission Disassembly

After motor and transmission disassembly, here the empty aluminium chassis for to start the assembly of the new tilting RC model vehicle.

Step 6 : Steering Servos Disassembly

For to replace the new steering servos (3kg-cm torque) has been necessary to cut the servos place in two parts then installed a new servos with 9kg-cm torque for front tilting gears system used for to lean the model.

Step 7 - New Servos Place

From this place starting for new servos steering linkage and tilting system.

Step 8 : New Steering/tilting System

Removing material from upper suspensions for to give place to shocks during the leaning phase; the shocks linkage made by a "meccano" bars. With arrow I can show the new servos lever that will work on gears tilting system.

Step 9 : Design and Calculation

Starting with transmission ratio calculation for to get the same transmission ratio of original kit; then with rear drive toothed gear, toothed gear pitch and rear wheel drive axis position for to calculate the toothed belt diameter.

The toothed belt size due also to the particular rear shocks position, linked on upper support and on arms suspensions.

The shocks inclination due also for to get a right position of the arms (made in aluminium bars) and wheel on the floor.

Step 10 : Rear Wheel Suspension

The rear drive wheel is connected to the axle shaft of original kit model by a new aluminium links suspension; to the axle shaft is connected a inner toothed gear and the toothedbelt transmission.

Step 11 : New Aluminium Parts Cutting Edge

For new aluminum parts cutting has been used a laser cut machine, the thickness is 2mm for all parts.

Step 12 - New Rear Motor and Gears Transmission Support

For the motor support has been used an aluminium part linked on old kit chassis; here is linked also the original kit transmission gears.

Step 13 - Front Tilting System

The front tilting system has a triangular aluminium part for the gears connect, the two gears are moved by servo lever and are linked to shocks "meccano" bar linking.