Data logger science experiment
Technicians notes
Apparaturs list
The items below are required for the construction of the Beagle 2 lander model:
- 1 force sensor FSG15N1A (Farnel InOne 721-6671)
- 1 force sensor mounting bracket (Farnel InOne 721-6683)
- Plastic downpiep (Marley 68mm RPH252BX)
- Quickset cement
- 2 4mm socket red (JPR 705-230)
- 2 4mm socket black (JPR 705-231)
- 1 1N4001 diode (JPR 1N4001)
- 1 PP3 battery clip (JPR 440-006)
- 1 9V PP3 alkaline battery*
- 1 4mm plug red (JPR 706-197)
- 1 4mm plug black (JPR 706-198)
- 1 socket housing 4-way (JPR 710-604)
- Crimp terminals (JPR 710-660)
- Thin connecting wire
- Small screw eye
- Small Plastiplug
- Terry clip to fit PP3 battery
- Dowelling to fit retort stand boss
- Thin wooden or plastic rod to anchor string
- Styrene sheet 2mm * 10cm * 10cm (W Hobby or local model shop)
- string
- screws
- yellow paint
* A supply voltage of between 10V dc and 12V dc maximum is specified but a 9V PP3 alkaline battery was found to work OK.
Construction method
Saw off two lengths of plastic downpipe 2.5cm and 3.5cm in length to make the model moulds. Put a little oil or soap solution around the insides of the moulds. Place these in a tray, pour in quickset cement and leave to dry.
Figure 1: Beagle 2 model
Release the model from the moulds by sawing carefully through the plastic sides at one point. Drill holes in the cement cylinders as shown in Figure 1 and paint the cylinders yellow. Fit a small Plastiplug into the back/topside of each and fit a screw eye into these. Fit another small Plastiplug into the hole with which to attach the sensor mounting bracket, screw the bracket in place with the force sensor. Crimp four thin insulated leads of length 50cm each to the crimp terminals and inset the latter into the socket housing. Pass the wires through the outer hole in the cement cylinder and through the screw eye. Push the socket housing onto the force sensor.
Figure 2: Sensor platform
Construct the sensor platform as shown in Figure 2 above and solder the leads to the appropriate sockets, incorporating a 1N4001 diode into the +9V battery line with its band (cathode end) furthest from the red 4mm socket. This diode will protect against reverse battery connections to the force sensor. Figure 3 below shows the connections to the force sensor.
Figure 3: Connections to the force sensor
Finally, tie a 40cm length of string to the screw eyes and pass this through the platform's central hole and tie to a thin plastic or wood rod to anchor it. Screw the Terry Clip in place on the underside of the platform. Connect a red and black 4mm plug, as appropriate, to the PP3 battery clip.
UK suppliers
Farnell InOne
Canal Road
Leeds
LS12 2TU
Tel: 0870 1200 200
Web: www.farnell.com
W Hobby Limited
Knight's Hill Square
London SE27 0HH
Tel: 020 8761 4244
Web: www.hobby.uk.com
JPR Electronics Ltd
Unit 4, Circle Business Centre
Blackburn Road
Houghton Regis
Dunstable
Tel: 01582 470000
Web: www.jprelec.co.uk
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