Powering On Sequence (Blue Headlights, Add Blue Side Lights, Add Blue Tail Lights, Flash Purple and Blue)
Idle Mode (Transition Blue > Purple and repeat)
Idle Mode happens between when the RVR has been turned on and when it is given a command OR when it has been a bit since it was last being given a command. Once the RVR has been been idle for 5 min it will go into Soft Sleep.
Entering Soft Sleep (Blue > Purple > Black)
Soft Sleep (2 Second Purple Pulse every 10 seconds)
Your RVR will go into Soft Sleep after having been idle for 5 minutes, in order to save power. The RVR can still be contacted and information can be requested of it while it is in Soft Sleep, but it will not respond to commands to take an action (such as driving).
Firmware Update (2 Second Orange Pulse)
Your RVR will pulse orange when it is waiting for a firmware update or when a firmware update is already in progress.
Low Battery (Red Flashing)
Your RVR's battery level is getting low and we want to give you time to get to a good stopping point; once you've found one, power RVR off, use your "key" to open up the battery compartment and eject the battery in order to plug it into a USB-C compatible charger.
Critical Battery (Very Quick Red Flashing)
Your RVR's battery level is low enough that it will soon power itself off. If you have a board, like a Raspberry Pi, being powered by your RVR, if the RVR "unexpectedly" powers off, it could cause damage to your board; please power down your board immediately and then charge your RVR's battery by powering RVR off, using your "key" to open up the battery compartment and ejecting the battery in order to plug it into a USB-C compatible charger.
While RVR has been created to be able to handle most anything you throw at it, it does have its limits. One of the ways in which we attempt to help you help your RVR be its best self is by triggering partial- or full-system shutdowns to stop the RVR in its tracks and allow it to recover from the action that was stressing its system. When these shutdowns occur, depending on the reason for the shutdown, there are certain steps that allow you and your RVR to get back up and running:
Motor Stall (Flashing Yellow and Red)
There are several reasons that the motor on RVR might stall:
- You continue sending drive commands to RVR while the wheels are stuck
- RVR has a payload that is too heavy
- RVR is going up an incline that is too steep
- RVR is spinning at a speed that causes too much stress on the motors
- RVR is stuck driving against a surface
- The treads are being held or restrained in a way that causes stress on the motors
If this happens, the motors will shut down (i.e. RVR will be unresponsive to any drive command) for a few seconds, and then resume normal operation. Additionally, if motor stall notifications have been enabled via the SDK, RVR will send notifications (1) when the motors stall, as well as (2) when RVR can resume normal operation, following a stall.
With all of that said, to prevent the RVR from repeatedly stalling, we recommend that you:
- Reduce the payload RVR is carrying (if there is one)
- Ensure you are not driving RVR up exceedingly steep inclines
- Reduce the amount of spinning RVR does
- Reduce the amount of time RVR is driving against a wall or surface
- Don't hold or restrain the treads while the motors are active
Motor Thermal Protection (Pulsing Red and Orange)
In an attempt to prevent RVR from overheating, we've implemented a system to monitor the RVR for activities that have produced enough thermal energy to risk damaging your RVR. In the event that a buildup in thermal energy (aka heat) has occurred in the motors, the motors on RVR will shut down, RVR will be unresponsive to drive commands and the LEDs will display a pulsing red and orange pattern. There are API commands to be notified of the Motor Thermal Protection Status or to be notified when the Motor Thermal Protection Status changes which may help you prevent your RVR from entering Thermal Protection Mode, in the first place.
Certain activities can cause your Sphero RVR to heat up quickly. Here are a few of the most common ones:
- Driving for a long period of time without a pause or break
- Driving up steep inclines
- Running programs that have RVR spin frequently, especially at lower speeds
- RVR has a payload that is too heavy
- Running programs that loop for a long time
When RVR enters Thermal Protection Mode, there is a series of events that occurs behind the scenes to monitor the recovery process; with this being the case, the RVR must be powered on throughout the entire recovery process. While "turning the machine off and on again" is often an effective method of helping stalled programs along, this recovery program becomes extra cautious if power is cut during its operation and doing so may delay the total cool-down time.
When the cool-down program has completed, the headlights stop pulsing red and orange and the thermal protection status changes to “OK” (if notifications are turned on); if motor thermal protection notifications have been enabled, RVR will send notifications for when a status change occurs pertaining to the thermal protection (letting you know both when thermal protection has been initiated and when it has finished running.
Motor Fault (Red/Orange/Yellow Pulsing)
(Gif soon to come!)
If your RVR's LEDs have begun flashing in a fiery red/orange/yellow pattern, motor fault has occurred. Motor fault is an indication of a failure in the motor system due to extremely high current and could indicate that damage has occurred. Luckily, if motor fault notifications have been enabled, you will receive a notification when motor fault has occurred.
Should a motor fault warning occur (or motor fault itself), turn your RVR off for 20 min and then turn it back on and reconnect it to the Sphero Edu app, to reset it.
eFuse (Yellow Flashes)
eFuse will be triggered if too much current is being "requested" from RVR’s user ports (USB and 4-Pin UART). RVR is designed to deliver 2.15 amps; more current than that will trigger the eFuse, in which case, RVR’s headlights will display a yellow flashing light.
Should you encounter an eFuse warning sign, check the draw of the attached equipment and, if necessary, either use a breadboard with resisters to connect your external equipment to your RVR, like in our Ultrasonic Example OR use an external battery to power your external equipment. Once the potential issue has been addressed, you can resume normal operation by restarting your RVR.
Bad Main App (Long Red Pulses)
Catastrophic Error ("Police Lights")
Catastrophic Nordic Error (Alternating red and blue)
Catastrophic ST Error (Alternating red and blue, with solid green light at the rear)
The most common cause of the "police light" pattern is a problem with a firmware update. If you previously attempted a firmware update, and you see this occur, retry the firmware update until it reaches 100% completion. If you did complete a firmware update, and you see this light pattern, please contact our customer support.