Slot car racing has been around for more than 40 years and has changed very little in that time.
Basically, only one car can be raced in each slot (or lane) and to race 6 cars together at the same time requires a track with 6 lanes which is very wide and impracticable in most private homes which is where most racing takes place. Also, in a turn, the car in the outer lane travels in a very wide radius turn whilst the car in the inside lane travels in a very tight radius turn. This is not at all like real motor racing.
Recently, some improvement has been made with the introduction of 'Digital' slot racing whereby up to 6 cars can be raced on a 2 lane track and lanes can be changed at designated points around the track.
This system still has many unsatisfactory aspects however;
1. The cars are guided by a slot in the track. This does not look realistic. Real race tracks or circuits do not have two slots 4 inch ( 10cm) wide running around them!
2. Power to the cars is picked up from 3/16inch or 5mm wide metal strips either side of the slot. Again real tracks do not have this. It is therefore impossible to build a slot car track which looks realistic.
3. The metal strips tarnish and require frequent cleaning.
4. Electrical connections to all sections of the track must be maintained at all times. Any movement of the track can break this.
5. With digital slot racing, lane changing is achieved by means of a moveable point or frog set into the slot. These are visible, expensive and difficult to fit to home built tracks.
6. Each lane change contains a short dead section. If the car stops on this, it will not restart.
7. Lane changing is achieved by the press of a button. There is no left or right steering action to be made by the driver.
8. If the number of cars racing changes during a race, the current drawn can vary giving rise to surges or drops in speed.
9. Cars cannot cut corners and follow the correct racing line.
10. Car controllers require wire connections to the track at a fixed point.
11. The high voltages used (12v+) has encouraged the development of cars which race at ridiculously unrealistic scale speeds, often over 500 mph!
Radio controlled model car racing is also a well established hobby and radio controlled model cars can nowadays be manufactured in very small scales, ie. down to 1/32 scale similar in size to slot cars, and this would seem to be the answer except for one major problem. For various reasons of scale time, friction, air drag and human reaction times, driving such small models accurately is virtually impossible. Tracks need to be more than 1 metre wide and even then overtaking without a collision cannot be guaranteed! Many manufacturers have marketed such cars but with very limited success from a racing standpoint.
MAG-racing (Patented) solves or improves upon all of these problems by combining the best elements of both systems..
The cars are guided basically by a magnet following a steel wire embedded in the track . They can be steered from one side of the track to the other by radio control. Speed is controlled by radio and cars are powered by a single rechargeable Lithium ion cell. Run times are in excess of 10 minutes using a single AAA cell which is inexpensive and quickly recharged.
The battery is located underneath the car, held in place by a magnet (patented) and, for a pit stop can be changed in less than 10 seconds!
There would normally be two guide wires around the track forming two lanes and six or more cars can race by employing different radio frequencies. Cars can change lanes to overtake,can take the fastest line through each turn by approaching in the outside lane, turning early to clip the apex and finishing back on the outside of the track. They can also turn into the pit lane when required. All this on a track of only (for 1/32 scale) 16cms wide with no slots, pick up tapes or lane change points to spoil it's appearance.
The speed of the cars is much closer to scale speed ( perhaps 200mph!) so in action they look much more realistic than slot cars or indeed 1/12 scale free running r/c cars. Because the front wheels steer, we again see greater realism. When driven too quickly, the cars will either spin or understeer off the track. This is of benefit because, if the car runs completely off the track, it cannot block following cars which often happens with digital slot racing. Marshalling a car is easier than slot racing as the car need only be placed on the track pointing in the right direction and it soon picks up a guide wire. Ideally tracks should have a marshalling point guide on the outside of each turn so that the cars can be driven back onto the track when the road is clear.
The idea of steering vehicles by magnet and guide wire is not new but what is new is this systems ability to change from one guide wire route to another. This is achieved by removing a short length of the guide wire at the desired lane change point. At this point, it is then possible to change the direction of the car by means of a radio controlled actuator in the car. This steering actuator turns the wheels just sufficiently for the car to leave it's straight line course and to realign with another guide wire. This wire can then lead the car to the alternative lane or to the fastest line route around the turn or to the pits lane, etc..
This track system is extremely simple and inexpensive to construct and maintain.
The power of the r/c steering actuator is adjusted to be less than the power of the magnetic guidance because it is usual to apply the r/c steering some distance before the car reaches the lane change point and to hold it until the car has passed the point. (It is not possible to apply the steering exactly when the car reaches the lane change as this is only approx 2cms long) If the r/c steering were stronger than the magnet, the car would turn off the track. This idea and and other features are covered by patents.
A racing scenario would see up to six cars running on the two lanes. If two cars approach a turn side by side, the car in the outside lane would be forced to forego the fastest line route and stay in the outside lane. This happens by default. A track can have many lane change points around it but this may not necessarily be for the best. On the test track shown, there are three lane change points, four turns with fastest line options and a pits lane. In a race, on a typical lap, the driver has up to eight steering decisions to make in addition to watching other traffic and controlling the speed of his car, all in the space of around 12 seconds!
As in full size motor racing, it is necessary to learn the track and small arrows painted on the track indicate where the lane change points are, but at racing speeds the driver must remember where they are.
Track
Prototype tracks use MDF board with routed slots 2mm x 2mm deep to accept 2mm diam. steel wire, held in place and disguised with filler. A variety of methods and materials could be used for production.
 |
Diagram showing guide wire layout for a typical track. |
Radio equipment
Racing on the test circuits has been restricted by the lack of suitable radio control equipment. The transmitter shown is perfect in size and shape but does not have a frequency changing ability and has only one forward speed. The prototype cars, being fairly high geared, are drivable like this ( Early slot racing ran for some time using full speed only controllers) . Proportional speed control would be ideal but two speeds, which are easily achievable in lieu of forward and reverse, would be quite acceptable. Reverse is not really of use. For steering, a simple left or right coil and magnets actuator is all that is necessary. There is no need for proportional steering. Range required is no more than 20ft (6 mtrs) and all prototype cars have been run without external aerials which is important in maximising realistic appearance.
Cars
Prototype cars use 1/32 slot car and r/c car wheels and gears. Motors are 3-6volt.
The AAA lithium cell gives 3.7volts which is adequate for speed and for the radio and actuator. A flat lithium cell could be used if preferred but the AAA cell does have some design advantages. In the prototype cars, the cell is loaded through a slot underneath the car and held in place with a small magnet. This works excellently and batteries can be changed in a matter of seconds!
Lap Counting
At the time of writing, a number of systems are being evaluated and a successful outcome is expected.
Summary
This is a revolutionary new r/c race system and continued development and improvement can be expected. It is not envisaged as a replacement for a slot racing set for 5 - 10 year olds set out on the home floor but as a new hobby for adult model car or motor race enthusiasts who appreciate the realism and driving skills which this system offers and who are prepared to devote permanent space for a race circuit where serious competition can take place. The system offers much greater scope for those who enjoy modeling scenic effects and realistic dioramas such as those created by model railway enthusiasts can now be achieved. |
