Given the spectacular success of "Sojourner" on Mars space exploration planners are looking at the possibility of a manned mission to Mars.  They want to include on this mission a radio-controlled vehicle to retrieve small rock samples.

Your job is to design and build a vehicle which will retrieve such a rock and bring it to a designated spot.  The vehicle must then return to its starting location and configuration, ready for another run.   It must be able to surmount small obstacles (simulated by lengths of wooden "2x4" studding) both in getting to the rock and in bringing the rock back to the designated deposit area.

The test course will consist of a flat, level, uncarpeted section of floor marked off with masking tape.  Opposite corners of the rectangular course will be at coordinates (0,0) and (90,144) inside the tape (all dimensions are in inches).  There will be three barriers.  The first will completely cross the course from (0,70) to (90,53).  (All coordinates will be to the "origin" side of the barrier and from the inside edges of the tape.)  The second barrier will go from (14,90) to (90,90), and the third barrier will go from (0,118) to (70,110).  The barriers may be constructed from two 2x4's nailed wide sides together and standing with the 3.5 in direction up, or from one 4x4 (3.5 inches square).  (Note that these barrier construction methods give different thicknesses.)  The rock to be picked up will start at (16,130).  A 12x24 in parking area will be marked off with its diagonal corners at (74,4) and (86,28).   A rock deposit target will be centered at (24,24).

The rock deposit target will consist of a series of 10 concentric circles with radii ranging from 1 in to 11 in in one inch increments.   The innermost area will be labeled "0", the next concentric circular area will be labeled "1", and so on.

Teams or contest organizers will need to find or provide their own rocks for testing, subject to the following specifications:
The rocks will range in size up to 1.5 inches across the widest dimension and will be at least 0.75 inches across any other "major" dimension; they will weigh between 0.35 and 2.8 ounces (10 to 80 grams);  they will be irregular in shape; and they will not roll more than one-half of a rotation when placed on a flat surface.  Simulated rocks may be made from plaster of paris if that is more convenient.

The vehicle may be controlled either through radio links or, in this simulation study, through an umbilical cord which carries no significant power.  Forces on the umbilical cord may not be used to help propel or control a vehicle.  At the start signal the vehicle must proceed down the course, climb over or maneuver around the obstacles, pick up the rock, bring the rock back over or around the obstacles, deposit the rock as nearly as possible on the center of the deposit target, then return to the parking area.  Time stops when the vehicle is once again stationary inside the parking area and in its starting configuration after depositing the rock.  A maximum of four minutes is allowed to complete the one run.  The vehicle may not be touched or altered between runs.

The vehicle must be powered by readily available, over-the-counter alkaline batteries.

Any vehicle which touches the tape or the floor outside the course boundary during a run will incur a one minute penalty for each excursion. In addition, any vehicle which leaves the course must re-enter the course at the point of departure without being intentionally repositioned by anyone.

The vehicle and all control equipment  must fit in a closed "Popular Mechanics 16 inch Tool Box", Popular Mechanics item number PM00983, available at department stores such as Wal-Mart or K-Mart.  The inside tray may be removed.  (Alternatively, the vehicle must fit within a box measuring 370x165x165 mm.) The vehicle must come from the box fully assembled.  Any expansion or extension must be done by the vehicle itself during the competition run.  However, an antenna wire may "spring up" on its own and remain upright without penalty even though outside the size restrictions.

The winning device will have the lowest score S from two runs where S = 2W+ 10(d1+d2)+ 4(t1+t2).

In this equation "W" is the weight of the vehicle in grams, d1 and d2 are the scores read from the rock deposit target circles when everything has come to rest after each run, and t1 and t2 are the times in seconds required to successfully complete the task for each run from the start signal to the time when the vehicle is once again stationary in the parking area. If a connector is provided on the vehicle so that the umbilical cord may be detached the vehicle weight will not include that of the umbilical cord.  If a connector is not provided then umbilical cord and control unit must be included in the vehicle weight.  Any parts of a radio controller which are not on the vehicle will not be included in the weight.   The rock must not touch outside the largest circle and the vehicle must be in its stored position inside the parking area for a valid run. A time of 500 seconds and a target score of 20 will be recorded for unsuccessful or invalid runs.

Rock placement "d" will be scored according the outermost point of contact between the rock and the target.  A rock touching a line will be scored at the higher distance.

Note:  Box dimensions corrected 4/6/98 CJH:  Rock weights corrected 7/7/98 CJH