Photoroller

When the ancient man lit the first spark of fire, he changed the world! Today, in what seems to be the twilight of petroleum machines, the world now again needs a spark! The need for newer technologies to harness renewable sources of energy is becoming more pressing by the day. Solar powered machines are the future and what today may seem to be a utopian world is, in fact, the inevitable destiny. Many milestones yet remain to be achieved in the field of harnessing solar energy and in a small attempt from our side, we bring you PHOTOROLLER. Put your imagination to work and build an efficient solar bot which will cover a given track length in the shortest amount of time using nothing but a given light source as energy.

Sounds difficult? Try it!

1. Problem Statement

Construct a machine which uses solar power as the only source of energy to race a 1000mm straight track in the minimum time.

To see the Photovore (Final Round) problem statement, click here.

View the Arena »

For further queries contact:

2.1 Arena

The racing strip is composed of two side by side 1000mm lanes of clean, smooth, level, flat plywood, with 25mm high white walls along both sides of each lane. The arena is lit up with two 500W halogen lamps, 500 mm above the track. The light source for the table will be positioned so that no shadows fall from the sides of the vertical walls.The machines will start off with the light source directly above them and it will be at an acute angle at the finish line. The race will be conducted indoors.

Figure 1

View the Machine Specifications »

3.1 Dimensions and Fabrications

1. The machine must fit within a box of dimensions 150 mm X 150 mm X 150 mm at the beginning of the race. The machine, when put in the arena at the start of the game, should have the same size as checked with the dimension box above.
2. During the game, the machine can expand or detach itself into multiple parts provided it does not damage the arena in any way. However, the entire machine should cross the finish line to complete the objective. The judges hold the right to subjectively determine if the machine violates this clause.
3. Machines cannot be constructed using readymade Lego kits or any readymade mechanism but use of readymade gear assemblies is allowed. Violating this clause will lead to disqualification of the machines. Judges hold the right to subjectively evaluate this clause.

3.2 Power Supply and Propulsion

1. The machine cannot use any other energy source than what they are able to draw from their solar cell. No pre-tensioned springs, elastics, combustion or compressed energy sources are allowed, though any of these may be employed in the design so long as it can be proved that they are at a complete state of rest at the beginning of the run. The judges hold the rights to disqualify the machine, if they are not convinced.
2. The method of propulsion is at the discretion of the participant provided it does not damage the arena in any way and it satisfies the safety constraints determined by the judges.
3. The size of the solar cell must not exceed 50 cm² in size.
4. The team must devise a mechanism to discharge its stored energy. For example shorting wires for the capacitor if the capacitor mechanism is used. The team will be asked to activate this mechanism at the beginning of every race.

3.3 Controls

The machine must be autonomous and cannot be externally controlled.

View the Rules »

4.1 Competition Rules:

1. Each machine will be given two runs, and the run in which it takes the least time to cover 1000mm will be counted. However if the machine does not complete the track in 5 minutes, the distance travelled by it will be noted down. Sufficient time will be provided between the two runs for minor changes.
2. The machine which takes the least time to cover the track or the machine which travels furthest in 5 minutes is the winner.
3. The team is only allowed to touch his machine once at the start of the race to disengage the discharging mechanism, however if he wishes to touch the machine, he needs to restart from the start line and the total time from the first run will be counted. The handling time is also included in the total race time and no extra time will be allocated. However the team need not engage his discharge mechanism at this point.
4. During racing the machine must not physically touch or attempt to touch each other and cross over to the other track, judges hold the rights to disqualify a team in this case.
5. Participants should not dismantle their machine till the completion of competition. It is subjected to verification by judges.

4.2 Team Specifications

A team must consist of 3 or less participants. Students from different educational institutes can form a team.
All students with a valid identity card of their respective educational institutes are eligible to participate in Photoroller at Techfest Nexus.

4.3 General Rules

1. The teams must adhere to the spirit of healthy competition. The teams must not damage the opponent's machine in any way. Judges reserve the right to disqualify any team indulging in misbehavior.
2. Any team that is not ready at the time specified will be disqualified from the competition automatically.
3. The machine would be checked for its safety before the race and would be discarded if found unsafe for other teams and spectators.
4. The name of your machine must be prominently displayed.
5. Judges decision shall be treated as final and binding on all.
6. The organizers reserve the rights to change any or all of the above rules as they deem fit. Change in rules, if any will be highlighted on the website and notified to the registered teams.

4.4 Registration

Registrations for Photoroller have ended.

View the Resources »

5.1 Resources

Make a photoroller in 3 easy steps. Click here to download the tutorial.

Adobe Acrobat Reader is required to view the pdf. To download Acrobat Reader, click here.

The following links might help you out in making a photoroller. After going through these links, you would notice that making a photoroller is one of the easiest things in the world.

1. www.solarbotics.net/library/circuits/se.html
2. www.faq.solarbotics.net/oscillate.html (Solar Engine Circuit)
3. www.talkingelectronics.com/projects/Robots/Page1.html
4. www.cachefly.oreilly.com/make/mc_beambots.pdf
5. www.ffaat.pointclark.net/blog/pages/BeamRoller2.html
6. www.triindia.co.in/resources

Imported Solar Cells are available online at:

1. www.robosoftsystems.co.in/roboshop.html.

Solar Cells can be bought online from:

1. www.solarbotics.com.
2. www.triindia.co.in/shop/index.php?cPath=55.
3. www.onlinetps.com/ShowCategory.php?Start=5&ByPage=5&CategoryID=15&SubcategoryID=.
4. www.robotz.in/store

In India, solar cells are available at the following retailers (NOTE: These are few of the many retailers):

1. Hyderabad

• Roland Electronics,
  4-3-345/5, Gujrati Galli, Koti, Hyderabad. Phone: 91-40-2475 6823, 91-9849070411
• Sanghvi Brothers
• Kishore Electronics

2. Mumbai

• Gala Electronics,
  21, Kalpana Bldg, 1st Floor, 357, Lamington Road, Mumbai. Phone: 91-22-2387 9562. email: vega63@vsnl.com
  www.vegakitindia.com
• Robosoft Systems,
  A61 Raj Industrial Complex, Military Road, Marol, Andheri (E), Mumbai - 400059. Phone: 91-9869194593 email: fahad.robosoft@gmail.com
  www.robosoftsystems.co.in
• Viraj Electronics,
  Shop no. 10, Mochi Building, Near Police Station, Netaji Subhash Road, Mulund (W).
• Apte Electronics

3. Vadodara

Name Electronics,
Marimata land, Rajmahal Road, Vadodara.

4. Bhopal

Jain Radios,
122, Marwari Road, Bhopal. Mobile: 09826241760.

5. Ahmedabad

Delta Electronic Parts,
27, Sanskar Complex, Near Ketav Petrol Pump, Polytechnic Road, Ambavadi, Ahemadabad.

6. Indore

Natwarlal and Co.,
35, Khatipura, Near Jail Road, Indore. Mobile: 09425318154. email: natwarlal_co@yahoo.co.in

7. Surat

Rajani Radios,
9/60, Wadifalia, Kotsafil Road, Near Canara Bank, Surat.

DC-DC converter

If you use the typical Imported Solar Cells (which have currents around 20 mA and voltages around 5-6 V) then you do not need a DC-DC converter. But if you use the typical solar cell which is available in India, they have voltage around 2 V and current around 150mA, so here when you charge a capacitor in the solar engine it charges only up to 2 V, but if you use a DC-DC converter,which changes the voltage to 5v and decreases the current proportionally and hence the capacitor can be charged to a higher value and can discharge giving more power.

You can buy/get a sample at: www.austriamicrosystems.com/03products/products_detail/AS1321/description_AS1321.htm.