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  1. Use a LiPo battery instead. Like a 3 cell cell used for RC cars. These batteries are good at delivering loads of power during peak activities.
    1. Having more Volts at the battery will allow you to use more power (amps) after it has been regulated. 12v, 15v or even 18v battery cells.
    2. Try to use switching regulators as they are more efficient than traditional transistor regulators. The UBEC is a good example of efficient regulator but is more expensive than a stand alone regulator.
    3. The 9volt battery is not going to last long as its best used for low activity devices. Like smoke detectors.
  2. Capacitors will help smooth out power dips but they are most effective as close as possible to the source of high drain, after voltage regulators.
    1. So a capacitor near each motor and near the Wifi. Suggested to use low emf labelled, something like 200uf for motors and 400uf for WiFi. Those are ball park figures though.
    2. The voltage rating must be more than the voltage being used. So if your motors run 6volt use a 10volt cap. Even if you are using 2 volts 10volt caps are fine as long as they are higher than required voltage.
  3. Power the Pi and motors using their own dedicated cables, regulators and capacitors directly from the battery. This prevents voltage dips on the "rail" and the capacitors help smooth out the "rail" during peak current draw.If all motors draw a large current the Pi will be less effected by this as its regulating its own "rail" supply and relies on its own filtering capacitor.
    1. As you have the motor wired directly to the Pi's I/O- That is the first thing that needs to be moved to its own power rail, complete separate from the Pi.
    2. I/O's are used as low voltage gates that control other devices, like relays or transistors. Running motors of the GPIO will cause the Pi to reset constantly.
  4. Calculate the peak current in amps used per rail and make sure the gauge of the copper cable can handle this efficiently. To thick cable causes unnecessary resistance and to thing cable will not be able to deliver peak power requirements. Refer to ohms triangle. Amps = Power (Watts) / Volts
    1. The Pi Model B clearly needs a good 1 amp supply but it draws about 300~600ma on its own. Adding WiFi to the USB port will start to reach 1 amp during peak. That mean the Pi could use up to 5 Watts of power.
    2. All these calculations help you determine the best battery and regualtors to use.
    3. Your motors, for example are rated at 5 watts using 9 volts. That is 0.55 amps per motor during full load! That is just an example- I do not know what motors you are using.
  5. Under powering the Raspberry Pi will not damage anything. Brown outs caused by power dipping below a threshold will cause the GPU to reset. This reset might cause file system damage as it could have been writing something to the SD card and not had time to finish the process. There are very few devices that will get damaged if they are underpowered but they are usually commercial devices that use allot of power. The only thing you will experience is erratic behaviour form the Pi, WiFi dropping out and motors not running at full capacity.
  6. Drawing more current than designed for will inevitably cause permanent damage. Like burning the traces on a PCB or burning out regulators due to overheating. The Pi has a few poly-fuses that help protect against normal usage but using the GPIO's on the Pi give you unprotected access.
    1. For example the 5volt power rail on the GPIO, when used incorrectly can cause serious damage if shorted, back fed or applied with an incorrect voltage.
    2. That is why using buffers on the GPIO is very important but butter yet a requirement that is overlooked. Like previously mentioned, use them to control relays or cheap transistors like PNP 2N2222.
    3. Transistors are cool because you can reuse old "broken" power supplies (or other devices) transistors for simple power switching, like controlling motors. Just type in the transistor code into the internet and read the data sheet on how what the voltage and power limits are. Usually for low voltage application like this most will suffice if not overkill. But they are free :) You should learn how to test transistors though, to ensure you are not using the "broken" element that may cause you a sleepless night of tinkering.
    4. You may look at this simple circuitmay look at this simple circuit on how to use the GPIO to drive the transistor. 1 denotes a low power output which is connected to the BASE (GATE/SWITCH). It is 0v when off and 3.3v to "turn on" the circuit. The arrow tells you what way the circuit should flow. in NPN its from COLLECTOR --To-> EMITTER.
  1. Use a LiPo battery instead. Like a 3 cell cell used for RC cars. These batteries are good at delivering loads of power during peak activities.
    1. Having more Volts at the battery will allow you to use more power (amps) after it has been regulated. 12v, 15v or even 18v battery cells.
    2. Try to use switching regulators as they are more efficient than traditional transistor regulators. The UBEC is a good example of efficient regulator but is more expensive than a stand alone regulator.
    3. The 9volt battery is not going to last long as its best used for low activity devices. Like smoke detectors.
  2. Capacitors will help smooth out power dips but they are most effective as close as possible to the source of high drain, after voltage regulators.
    1. So a capacitor near each motor and near the Wifi. Suggested to use low emf labelled, something like 200uf for motors and 400uf for WiFi. Those are ball park figures though.
    2. The voltage rating must be more than the voltage being used. So if your motors run 6volt use a 10volt cap. Even if you are using 2 volts 10volt caps are fine as long as they are higher than required voltage.
  3. Power the Pi and motors using their own dedicated cables, regulators and capacitors directly from the battery. This prevents voltage dips on the "rail" and the capacitors help smooth out the "rail" during peak current draw.If all motors draw a large current the Pi will be less effected by this as its regulating its own "rail" supply and relies on its own filtering capacitor.
    1. As you have the motor wired directly to the Pi's I/O- That is the first thing that needs to be moved to its own power rail, complete separate from the Pi.
    2. I/O's are used as low voltage gates that control other devices, like relays or transistors. Running motors of the GPIO will cause the Pi to reset constantly.
  4. Calculate the peak current in amps used per rail and make sure the gauge of the copper cable can handle this efficiently. To thick cable causes unnecessary resistance and to thing cable will not be able to deliver peak power requirements. Refer to ohms triangle. Amps = Power (Watts) / Volts
    1. The Pi Model B clearly needs a good 1 amp supply but it draws about 300~600ma on its own. Adding WiFi to the USB port will start to reach 1 amp during peak. That mean the Pi could use up to 5 Watts of power.
    2. All these calculations help you determine the best battery and regualtors to use.
    3. Your motors, for example are rated at 5 watts using 9 volts. That is 0.55 amps per motor during full load! That is just an example- I do not know what motors you are using.
  5. Under powering the Raspberry Pi will not damage anything. Brown outs caused by power dipping below a threshold will cause the GPU to reset. This reset might cause file system damage as it could have been writing something to the SD card and not had time to finish the process. There are very few devices that will get damaged if they are underpowered but they are usually commercial devices that use allot of power. The only thing you will experience is erratic behaviour form the Pi, WiFi dropping out and motors not running at full capacity.
  6. Drawing more current than designed for will inevitably cause permanent damage. Like burning the traces on a PCB or burning out regulators due to overheating. The Pi has a few poly-fuses that help protect against normal usage but using the GPIO's on the Pi give you unprotected access.
    1. For example the 5volt power rail on the GPIO, when used incorrectly can cause serious damage if shorted, back fed or applied with an incorrect voltage.
    2. That is why using buffers on the GPIO is very important but butter yet a requirement that is overlooked. Like previously mentioned, use them to control relays or cheap transistors like PNP 2N2222.
    3. Transistors are cool because you can reuse old "broken" power supplies (or other devices) transistors for simple power switching, like controlling motors. Just type in the transistor code into the internet and read the data sheet on how what the voltage and power limits are. Usually for low voltage application like this most will suffice if not overkill. But they are free :) You should learn how to test transistors though, to ensure you are not using the "broken" element that may cause you a sleepless night of tinkering.
    4. You may look at this simple circuit on how to use the GPIO to drive the transistor. 1 denotes a low power output which is connected to the BASE (GATE/SWITCH). It is 0v when off and 3.3v to "turn on" the circuit. The arrow tells you what way the circuit should flow. in NPN its from COLLECTOR --To-> EMITTER.
  1. Use a LiPo battery instead. Like a 3 cell cell used for RC cars. These batteries are good at delivering loads of power during peak activities.
    1. Having more Volts at the battery will allow you to use more power (amps) after it has been regulated. 12v, 15v or even 18v battery cells.
    2. Try to use switching regulators as they are more efficient than traditional transistor regulators. The UBEC is a good example of efficient regulator but is more expensive than a stand alone regulator.
    3. The 9volt battery is not going to last long as its best used for low activity devices. Like smoke detectors.
  2. Capacitors will help smooth out power dips but they are most effective as close as possible to the source of high drain, after voltage regulators.
    1. So a capacitor near each motor and near the Wifi. Suggested to use low emf labelled, something like 200uf for motors and 400uf for WiFi. Those are ball park figures though.
    2. The voltage rating must be more than the voltage being used. So if your motors run 6volt use a 10volt cap. Even if you are using 2 volts 10volt caps are fine as long as they are higher than required voltage.
  3. Power the Pi and motors using their own dedicated cables, regulators and capacitors directly from the battery. This prevents voltage dips on the "rail" and the capacitors help smooth out the "rail" during peak current draw.If all motors draw a large current the Pi will be less effected by this as its regulating its own "rail" supply and relies on its own filtering capacitor.
    1. As you have the motor wired directly to the Pi's I/O- That is the first thing that needs to be moved to its own power rail, complete separate from the Pi.
    2. I/O's are used as low voltage gates that control other devices, like relays or transistors. Running motors of the GPIO will cause the Pi to reset constantly.
  4. Calculate the peak current in amps used per rail and make sure the gauge of the copper cable can handle this efficiently. To thick cable causes unnecessary resistance and to thing cable will not be able to deliver peak power requirements. Refer to ohms triangle. Amps = Power (Watts) / Volts
    1. The Pi Model B clearly needs a good 1 amp supply but it draws about 300~600ma on its own. Adding WiFi to the USB port will start to reach 1 amp during peak. That mean the Pi could use up to 5 Watts of power.
    2. All these calculations help you determine the best battery and regualtors to use.
    3. Your motors, for example are rated at 5 watts using 9 volts. That is 0.55 amps per motor during full load! That is just an example- I do not know what motors you are using.
  5. Under powering the Raspberry Pi will not damage anything. Brown outs caused by power dipping below a threshold will cause the GPU to reset. This reset might cause file system damage as it could have been writing something to the SD card and not had time to finish the process. There are very few devices that will get damaged if they are underpowered but they are usually commercial devices that use allot of power. The only thing you will experience is erratic behaviour form the Pi, WiFi dropping out and motors not running at full capacity.
  6. Drawing more current than designed for will inevitably cause permanent damage. Like burning the traces on a PCB or burning out regulators due to overheating. The Pi has a few poly-fuses that help protect against normal usage but using the GPIO's on the Pi give you unprotected access.
    1. For example the 5volt power rail on the GPIO, when used incorrectly can cause serious damage if shorted, back fed or applied with an incorrect voltage.
    2. That is why using buffers on the GPIO is very important but butter yet a requirement that is overlooked. Like previously mentioned, use them to control relays or cheap transistors like PNP 2N2222.
    3. Transistors are cool because you can reuse old "broken" power supplies (or other devices) transistors for simple power switching, like controlling motors. Just type in the transistor code into the internet and read the data sheet on how what the voltage and power limits are. Usually for low voltage application like this most will suffice if not overkill. But they are free :) You should learn how to test transistors though, to ensure you are not using the "broken" element that may cause you a sleepless night of tinkering.
    4. You may look at this simple circuit on how to use the GPIO to drive the transistor. 1 denotes a low power output which is connected to the BASE (GATE/SWITCH). It is 0v when off and 3.3v to "turn on" the circuit. The arrow tells you what way the circuit should flow. in NPN its from COLLECTOR --To-> EMITTER.
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  1. Use a LiPo battery instead. Like a 3 cell cell used for RC cars. These batteries are good at delivering loads of power during peak activities.
    1. Having more Volts at the battery will allow you to use more power (amps) after it has been regulated. 12v, 15v or even 18v battery cells.
    2. Try to use switching regulators as they are more efficient than traditional transistor regulators. The UBEC is a good example of efficient regulator but is more expensive than a stand alone regulator.
    3. The 9volt battery is not going to last long as its best used for low activity devices. Like smoke detectors.
  2. Capacitors will help smooth out power dips but they are most effective as close as possible to the source of high drain, after voltage regulators.
    1. So a capacitor near each motor and near the Wifi. Suggested to use low emf labelled, something like 200uf for motors and 400uf for WiFi. Those are ball park figures though.
    2. The voltage rating must be more than the voltage being used. So if your motors run 6volt use a 10volt cap. Even if you are using 2 volts 10volt caps are fine as long as they are higher than required voltage.
  3. Power the Pi and motors using their own dedicated cables, regulators and capacitors directly from the battery. This prevents voltage dips on the "rail" and the capacitors help smooth out the "rail" during peak current draw.If all motors draw a large current the Pi will be less effected by this as its regulating its own "rail" supply and relies on its own filtering capacitor.
    1. As you have the motor wired directly to the Pi's I/O- That is the first thing that needs to be moved to its own power rail, complete separate from the Pi.
    2. I/O's are used as low voltage gates that control other devices, like relays or transistors. Running motors of the GPIO will cause the Pi to reset constantly.
  4. Calculate the peak current in amps used per rail and make sure the gauge of the copper cable can handle this efficiently. To thick cable causes unnecessary resistance and to thing cable will not be able to deliver peak power requirements. Refer to ohms triangle. Amps = Power (Watts) / Volts
    1. The Pi Model B clearly needs a good 1 amp supply but it draws about 300~600ma on its own. Adding WiFi to the USB port will start to reach 1 amp during peak. That mean the Pi could use up to 5 Watts of power.
    2. All these calculations help you determine the best battery and regualtors to use.
    3. Your motors, for example are rated at 5 watts using 9 volts. That is 0.55 amps per motor during full load! That is just an example- I do not know what motors you are using.
  5. Under powering the Raspberry Pi will not damage anything. Brown outs caused by power dipping below a threshold will cause the GPU to reset. This reset might cause file system damage as it could have been writing something to the SD card and not had time to finish the process. There are very few devices that will get damaged if they are underpowered but they are usually commercial devices that use allot of power. The only thing you will experience is erratic behaviour form the Pi, WiFi dropping out and motors not running at full capacity.
  6. Drawing more current than designed for will inevitably cause permanent damage. Like burning the traces on a PCB or burning out regulators due to overheating. The Pi has a few poly-fuses that help protect against normal usage but using the GPIO's on the Pi give you unprotected access.
    1. For example the 5volt power rail on the GPIO, when used incorrectly can cause serious damage if shorted, back fed or applied with an incorrect voltage.
    2. That is why using buffers on the GPIO is very important but butter yet a requirement that is overlooked. Like previously mentioned, use them to control relays or cheap transistors like PNP 2N2222.
    3. Transistors are cool because you can reuse old "broken" power supplies (or other devices) transistors for simple power switching, like controlling motors. Just type in the transistor code into the internet and read the data sheet on how what the voltage and power limits are. Usually for low voltage application like this most will suffice if not overkill. But they are free :) You should learn how to test transistors though, to ensure you are not using the "broken" element that may cause you a sleepless night of tinkering.
    4. You may look at this simple circuit on how to use the GPIO to drive the transistor. 1 denotes a low power output which is connected to the BASE (GATE/SWITCH). It is 0v when off and 3.3v to "turn on" the circuit. The arrow tells you what way the circuit should flow. in NPN its from Collector to EmmiterCOLLECTOR --To-> EMITTER.

As you can see this is purely electronics engineering and requires some time to think about the requirements and study other solutions.

Good luck with your PiCar :) , ;). I hope it becomes a success.

  1. Use a LiPo battery instead. Like a 3 cell cell used for RC cars. These batteries are good at delivering loads of power during peak activities.
    1. Having more Volts at the battery will allow you to use more power (amps) after it has been regulated. 12v, 15v or even 18v battery cells.
    2. Try to use switching regulators as they are more efficient than traditional transistor regulators. The UBEC is a good example of efficient regulator but is more expensive than a stand alone regulator.
    3. The 9volt battery is not going to last long as its best used for low activity devices. Like smoke detectors.
  2. Capacitors will help smooth out power dips but they are most effective as close as possible to the source of high drain, after voltage regulators.
    1. So a capacitor near each motor and near the Wifi. Suggested to use low emf labelled, something like 200uf for motors and 400uf for WiFi. Those are ball park figures though.
    2. The voltage rating must be more than the voltage being used. So if your motors run 6volt use a 10volt cap. Even if you are using 2 volts 10volt caps are fine as long as they are higher than required voltage.
  3. Power the Pi and motors using their own dedicated cables, regulators and capacitors directly from the battery. This prevents voltage dips on the "rail" and the capacitors help smooth out the "rail" during peak current draw.If all motors draw a large current the Pi will be less effected by this as its regulating its own "rail" supply and relies on its own filtering capacitor.
    1. As you have the motor wired directly to the Pi's I/O- That is the first thing that needs to be moved to its own power rail, complete separate from the Pi.
    2. I/O's are used as low voltage gates that control other devices, like relays or transistors. Running motors of the GPIO will cause the Pi to reset constantly.
  4. Calculate the peak current in amps used per rail and make sure the gauge of the copper cable can handle this efficiently. To thick cable causes unnecessary resistance and to thing cable will not be able to deliver peak power requirements. Refer to ohms triangle. Amps = Power (Watts) / Volts
    1. The Pi Model B clearly needs a good 1 amp supply but it draws about 300~600ma on its own. Adding WiFi to the USB port will start to reach 1 amp during peak. That mean the Pi could use up to 5 Watts of power.
    2. All these calculations help you determine the best battery and regualtors to use.
    3. Your motors, for example are rated at 5 watts using 9 volts. That is 0.55 amps per motor during full load! That is just an example- I do not know what motors you are using.
  5. Under powering the Raspberry Pi will not damage anything. Brown outs caused by power dipping below a threshold will cause the GPU to reset. This reset might cause file system damage as it could have been writing something to the SD card and not had time to finish the process. There are very few devices that will get damaged if they are underpowered but they are usually commercial devices that use allot of power. The only thing you will experience is erratic behaviour form the Pi, WiFi dropping out and motors not running at full capacity.
  6. Drawing more current than designed for will inevitably cause permanent damage. Like burning the traces on a PCB or burning out regulators due to overheating. The Pi has a few poly-fuses that help protect against normal usage but using the GPIO's on the Pi give you unprotected access.
    1. For example the 5volt power rail on the GPIO, when used incorrectly can cause serious damage if shorted, back fed or applied with an incorrect voltage.
    2. That is why using buffers on the GPIO is very important but butter yet a requirement that is overlooked. Like previously mentioned, use them to control relays or cheap transistors like PNP 2N2222.
    3. Transistors are cool because you can reuse old "broken" power supplies (or other devices) transistors for simple power switching, like controlling motors. Just type in the transistor code into the internet and read the data sheet on how what the voltage and power limits are. Usually for low voltage application like this most will suffice if not overkill. But they are free :) You should learn how to test transistors though, to ensure you are not using the "broken" element that may cause you a sleepless night of tinkering.
    4. You may look at this simple circuit on how to use the GPIO to drive the transistor. 1 denotes a low power output which is connected to the BASE (GATE/SWITCH). The arrow tells you what way the circuit should flow. in NPN its from Collector to Emmiter.

As you can see this is purely electronics engineering and requires some time to think about the requirements and study other solutions.

  1. Use a LiPo battery instead. Like a 3 cell cell used for RC cars. These batteries are good at delivering loads of power during peak activities.
    1. Having more Volts at the battery will allow you to use more power (amps) after it has been regulated. 12v, 15v or even 18v battery cells.
    2. Try to use switching regulators as they are more efficient than traditional transistor regulators. The UBEC is a good example of efficient regulator but is more expensive than a stand alone regulator.
    3. The 9volt battery is not going to last long as its best used for low activity devices. Like smoke detectors.
  2. Capacitors will help smooth out power dips but they are most effective as close as possible to the source of high drain, after voltage regulators.
    1. So a capacitor near each motor and near the Wifi. Suggested to use low emf labelled, something like 200uf for motors and 400uf for WiFi. Those are ball park figures though.
    2. The voltage rating must be more than the voltage being used. So if your motors run 6volt use a 10volt cap. Even if you are using 2 volts 10volt caps are fine as long as they are higher than required voltage.
  3. Power the Pi and motors using their own dedicated cables, regulators and capacitors directly from the battery. This prevents voltage dips on the "rail" and the capacitors help smooth out the "rail" during peak current draw.If all motors draw a large current the Pi will be less effected by this as its regulating its own "rail" supply and relies on its own filtering capacitor.
    1. As you have the motor wired directly to the Pi's I/O- That is the first thing that needs to be moved to its own power rail, complete separate from the Pi.
    2. I/O's are used as low voltage gates that control other devices, like relays or transistors. Running motors of the GPIO will cause the Pi to reset constantly.
  4. Calculate the peak current in amps used per rail and make sure the gauge of the copper cable can handle this efficiently. To thick cable causes unnecessary resistance and to thing cable will not be able to deliver peak power requirements. Refer to ohms triangle. Amps = Power (Watts) / Volts
    1. The Pi Model B clearly needs a good 1 amp supply but it draws about 300~600ma on its own. Adding WiFi to the USB port will start to reach 1 amp during peak. That mean the Pi could use up to 5 Watts of power.
    2. All these calculations help you determine the best battery and regualtors to use.
    3. Your motors, for example are rated at 5 watts using 9 volts. That is 0.55 amps per motor during full load! That is just an example- I do not know what motors you are using.
  5. Under powering the Raspberry Pi will not damage anything. Brown outs caused by power dipping below a threshold will cause the GPU to reset. This reset might cause file system damage as it could have been writing something to the SD card and not had time to finish the process. There are very few devices that will get damaged if they are underpowered but they are usually commercial devices that use allot of power. The only thing you will experience is erratic behaviour form the Pi, WiFi dropping out and motors not running at full capacity.
  6. Drawing more current than designed for will inevitably cause permanent damage. Like burning the traces on a PCB or burning out regulators due to overheating. The Pi has a few poly-fuses that help protect against normal usage but using the GPIO's on the Pi give you unprotected access.
    1. For example the 5volt power rail on the GPIO, when used incorrectly can cause serious damage if shorted, back fed or applied with an incorrect voltage.
    2. That is why using buffers on the GPIO is very important but butter yet a requirement that is overlooked. Like previously mentioned, use them to control relays or cheap transistors like PNP 2N2222.
    3. Transistors are cool because you can reuse old "broken" power supplies (or other devices) transistors for simple power switching, like controlling motors. Just type in the transistor code into the internet and read the data sheet on how what the voltage and power limits are. Usually for low voltage application like this most will suffice if not overkill. But they are free :) You should learn how to test transistors though, to ensure you are not using the "broken" element that may cause you a sleepless night of tinkering.
    4. You may look at this simple circuit on how to use the GPIO to drive the transistor. 1 denotes a low power output which is connected to the BASE (GATE/SWITCH). It is 0v when off and 3.3v to "turn on" the circuit. The arrow tells you what way the circuit should flow. in NPN its from COLLECTOR --To-> EMITTER.

As you can see this is purely electronics engineering and requires some time to think about the requirements and study other solutions.

Good luck with your PiCar :) , ;). I hope it becomes a success.

7 added 159 characters in body
source | link
  1. Use a LiPo battery instead. Like a 3 cell cell used for RC cars. These batteries are good at delivering loads of power during peak activities.
    1. Having more Volts at the battery will allow you to use more power (amps) after it has been regulated. 12v, 15v or even 18v battery cells.
    2. Try to use switching regulators as they are more efficient than traditional transistor regulators. The UBEC is a good example of efficient regulator but is more expensive than a stand alone regulator.
    3. The 9volt battery is not going to last long as its best used for low activity devices. Like smoke detectors.
  2. Capacitors will help smooth out power dips but they are most effective as close as possible to the source of high drain, after voltage regulators.
    1. So a capacitor near each motor and near the Wifi. Suggested to use low emf labelled, something like 200uf for motors and 400uf for WiFi. Those are ball park figures though.
    2. The voltage rating must be more than the voltage being used. So if your motors run 6volt use a 10volt cap. Even if you are using 2 volts 10volt caps are fine as long as they are higher than required voltage.
  3. Power the Pi and motors using their own dedicated cables, regulators and capacitors directly from the battery. This prevents voltage dips on the "rail" and the capacitors help smooth out the "rail" during peak current draw.If all motors draw a large current the Pi will be less effected by this as its regulating its own "rail" supply and relies on its own filtering capacitor.
    1. As you have the motor wired directly to the Pi's I/O- That is the first thing that needs to be moved to its own power rail, complete separate from the Pi.
    2. I/O's are used as low voltage gates that control other devices, like relays or transistors. Running motors of the GPIO will cause the Pi to reset constantly.
  4. Calculate the peak current in amps used per rail and make sure the gauge of the copper cable can handle this efficiently. To thick cable causes unnecessary resistance and to thing cable will not be able to deliver peak power requirements. Refer to ohms triangle. Amps = Power (Watts) / Volts
    1. The Pi Model B clearly needs a good 1 amp supply but it draws about 300~600ma on its own. Adding WiFi to the USB port will start to reach 1 amp during peak. That mean the Pi could use up to 5 Watts of power.
    2. All these calculations help you determine the best battery and regualtors to use.
    3. Your motors, for example are rated at 5 watts using 9 volts. That is 0.55 amps per motor during full load! That is just an example- I do not know what motors you are using.
  5. Under powering the Raspberry Pi will not damage anything. Brown outs caused by power dipping below a threshold will cause the GPU to reset. This reset might cause file system damage as it could have been writing something to the SD card and not had time to finish the process. There are very few devices that will get damaged if they are underpowered but they are usually commercial devices that use allot of power. The only thing you will experience is erratic behaviour form the Pi, WiFi dropping out and motors not running at full capacity.
  6. Drawing more current than designed for will inevitably cause permanent damage. Like burning the traces on a PCB or burning out regulators due to overheating. The Pi has a few poly-fuses that help protect against normal usage but using the GPIO's on the Pi give you unprotected access.
    1. For example the 5volt power rail on the GPIO, when used incorrectly can cause serious damage if shorted, back fed or applied with an incorrect voltage.
    2. That is why using buffers on the GPIO is very important but butter yet a requirement that is overlooked. Like previously mentioned, use them to control relays or cheap transistors like PNP 2N2222.
    3. Transistors are cool because you can reuse old "broken" power supplies (or other devices) transistors for simple power switching, like controlling motors. Just type in the transistor code into the internet and read the data sheet on how what the voltage and power limits are. Usually for low voltage application like this most will suffice if not overkill. But they are free :) You should learn how to test transistors though, to ensure you are not using the "broken" element that may cause you a sleepless night of tinkering.
    4. You may look at this simple circuit on how to use the GPIO to drive the transistor. 1 denotes a low power output which is connected to the BASE (GATE/SWITCH). The arrow tells you what way the circuit should flow. in NPN its from Collector to Emmiter.
  1. Use a LiPo battery instead. Like a 3 cell cell used for RC cars. These batteries are good at delivering loads of power during peak activities.
    1. Having more Volts at the battery will allow you to use more power (amps) after it has been regulated. 12v, 15v or even 18v battery cells.
    2. Try to use switching regulators as they are more efficient than traditional transistor regulators. The UBEC is a good example of efficient regulator but is more expensive than a stand alone regulator.
    3. The 9volt battery is not going to last long as its best used for low activity devices. Like smoke detectors.
  2. Capacitors will help smooth out power dips but they are most effective as close as possible to the source of high drain, after voltage regulators.
    1. So a capacitor near each motor and near the Wifi. Suggested to use low emf labelled, something like 200uf for motors and 400uf for WiFi. Those are ball park figures though.
    2. The voltage rating must be more than the voltage being used. So if your motors run 6volt use a 10volt cap. Even if you are using 2 volts 10volt caps are fine as long as they are higher than required voltage.
  3. Power the Pi and motors using their own dedicated cables, regulators and capacitors directly from the battery. This prevents voltage dips on the "rail" and the capacitors help smooth out the "rail" during peak current draw.If all motors draw a large current the Pi will be less effected by this as its regulating its own "rail" supply and relies on its own filtering capacitor.
    1. As you have the motor wired directly to the Pi's I/O- That is the first thing that needs to be moved to its own power rail, complete separate from the Pi.
    2. I/O's are used as low voltage gates that control other devices, like relays or transistors. Running motors of the GPIO will cause the Pi to reset constantly.
  4. Calculate the peak current in amps used per rail and make sure the gauge of the copper cable can handle this efficiently. To thick cable causes unnecessary resistance and to thing cable will not be able to deliver peak power requirements. Refer to ohms triangle. Amps = Power (Watts) / Volts
    1. The Pi Model B clearly needs a good 1 amp supply but it draws about 300~600ma on its own. Adding WiFi to the USB port will start to reach 1 amp during peak. That mean the Pi could use up to 5 Watts of power.
    2. All these calculations help you determine the best battery and regualtors to use.
    3. Your motors, for example are rated at 5 watts using 9 volts. That is 0.55 amps per motor during full load! That is just an example- I do not know what motors you are using.
  5. Under powering the Raspberry Pi will not damage anything. Brown outs caused by power dipping below a threshold will cause the GPU to reset. This reset might cause file system damage as it could have been writing something to the SD card and not had time to finish the process. There are very few devices that will get damaged if they are underpowered but they are usually commercial devices that use allot of power. The only thing you will experience is erratic behaviour form the Pi, WiFi dropping out and motors not running at full capacity.
  6. Drawing more current than designed for will inevitably cause permanent damage. Like burning the traces on a PCB or burning out regulators due to overheating. The Pi has a few poly-fuses that help protect against normal usage but using the GPIO's on the Pi give you unprotected access.
    1. For example the 5volt power rail on the GPIO, when used incorrectly can cause serious damage if shorted, back fed or applied with an incorrect voltage.
    2. That is why using buffers on the GPIO is very important but butter yet a requirement that is overlooked. Like previously mentioned, use them to control relays or cheap transistors like PNP 2N2222.
    3. Transistors are cool because you can reuse old "broken" power supplies (or other devices) transistors for simple power switching, like controlling motors. Just type in the transistor code into the internet and read the data sheet on how what the voltage and power limits are. Usually for low voltage application like this most will suffice if not overkill. But they are free :) You should learn how to test transistors though, to ensure you are not using the "broken" element that may cause you a sleepless night of tinkering.
  1. Use a LiPo battery instead. Like a 3 cell cell used for RC cars. These batteries are good at delivering loads of power during peak activities.
    1. Having more Volts at the battery will allow you to use more power (amps) after it has been regulated. 12v, 15v or even 18v battery cells.
    2. Try to use switching regulators as they are more efficient than traditional transistor regulators. The UBEC is a good example of efficient regulator but is more expensive than a stand alone regulator.
    3. The 9volt battery is not going to last long as its best used for low activity devices. Like smoke detectors.
  2. Capacitors will help smooth out power dips but they are most effective as close as possible to the source of high drain, after voltage regulators.
    1. So a capacitor near each motor and near the Wifi. Suggested to use low emf labelled, something like 200uf for motors and 400uf for WiFi. Those are ball park figures though.
    2. The voltage rating must be more than the voltage being used. So if your motors run 6volt use a 10volt cap. Even if you are using 2 volts 10volt caps are fine as long as they are higher than required voltage.
  3. Power the Pi and motors using their own dedicated cables, regulators and capacitors directly from the battery. This prevents voltage dips on the "rail" and the capacitors help smooth out the "rail" during peak current draw.If all motors draw a large current the Pi will be less effected by this as its regulating its own "rail" supply and relies on its own filtering capacitor.
    1. As you have the motor wired directly to the Pi's I/O- That is the first thing that needs to be moved to its own power rail, complete separate from the Pi.
    2. I/O's are used as low voltage gates that control other devices, like relays or transistors. Running motors of the GPIO will cause the Pi to reset constantly.
  4. Calculate the peak current in amps used per rail and make sure the gauge of the copper cable can handle this efficiently. To thick cable causes unnecessary resistance and to thing cable will not be able to deliver peak power requirements. Refer to ohms triangle. Amps = Power (Watts) / Volts
    1. The Pi Model B clearly needs a good 1 amp supply but it draws about 300~600ma on its own. Adding WiFi to the USB port will start to reach 1 amp during peak. That mean the Pi could use up to 5 Watts of power.
    2. All these calculations help you determine the best battery and regualtors to use.
    3. Your motors, for example are rated at 5 watts using 9 volts. That is 0.55 amps per motor during full load! That is just an example- I do not know what motors you are using.
  5. Under powering the Raspberry Pi will not damage anything. Brown outs caused by power dipping below a threshold will cause the GPU to reset. This reset might cause file system damage as it could have been writing something to the SD card and not had time to finish the process. There are very few devices that will get damaged if they are underpowered but they are usually commercial devices that use allot of power. The only thing you will experience is erratic behaviour form the Pi, WiFi dropping out and motors not running at full capacity.
  6. Drawing more current than designed for will inevitably cause permanent damage. Like burning the traces on a PCB or burning out regulators due to overheating. The Pi has a few poly-fuses that help protect against normal usage but using the GPIO's on the Pi give you unprotected access.
    1. For example the 5volt power rail on the GPIO, when used incorrectly can cause serious damage if shorted, back fed or applied with an incorrect voltage.
    2. That is why using buffers on the GPIO is very important but butter yet a requirement that is overlooked. Like previously mentioned, use them to control relays or cheap transistors like PNP 2N2222.
    3. Transistors are cool because you can reuse old "broken" power supplies (or other devices) transistors for simple power switching, like controlling motors. Just type in the transistor code into the internet and read the data sheet on how what the voltage and power limits are. Usually for low voltage application like this most will suffice if not overkill. But they are free :) You should learn how to test transistors though, to ensure you are not using the "broken" element that may cause you a sleepless night of tinkering.
    4. You may look at this simple circuit on how to use the GPIO to drive the transistor. 1 denotes a low power output which is connected to the BASE (GATE/SWITCH). The arrow tells you what way the circuit should flow. in NPN its from Collector to Emmiter.
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